[ { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/d8t5c-n5y66", "eprint_id": 98781, "eprint_status": "archive", "datestamp": "2023-10-03 16:59:39", "lastmod": "2023-10-24 15:29:08", "type": "book", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bellan-P-M", "name": { "family": "Bellan", "given": "Paul" }, "orcid": "0000-0002-0886-8782" }, { "id": "Grabbe-Crockett-Lane", "name": { "family": "Grabbe", "given": "Crockett L." } }, { "id": "Hedemann-Mark", "name": { "family": "Hedemann", "given": "Mark" } }, { "id": "Hwang-David-Q", "name": { "family": "Hwang", "given": "David Q." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } }, { "id": "Levine-Bruce-M", "name": { "family": "Levine", "given": "Bruce" } }, { "id": "Kubena-Randy", "name": { "family": "Kubena", "given": "Randy" } } ] }, "title": "Proceedings of the Third Topical Conference on Radio Frequency Plasma Heating: held at the California Institute of Technology, Pasadena, California, January 11-13, 1978", "ispublished": "unpub", "full_text_status": "public", "note": "
Published - Radio-Frequency-Plasma-Heating-1978.pdf
", "abstract": "[Session topics from Table of Contents)]: Lower Hybrid Heating I; Lower Hybrid Heating II; Ion Cyclotron Heating I; Ion Cyclotron Heating II; Lower Hybrid Heating III; Alfven Wave, TTMP and Other Heating; General Theory Relating to Heating", "date": "2019-09-23", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20190920-142014940", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190920-142014940", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Plasma-Laboratory" } ] }, "primary_object": { "basename": "Radio-Frequency-Plasma-Heating-1978.pdf", "url": "https://authors.library.caltech.edu/records/d8t5c-n5y66/files/Radio-Frequency-Plasma-Heating-1978.pdf" }, "resource_type": "book", "pub_year": "2019", "author_list": "Bellan, Paul; Grabbe, Crockett L.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/298gp-e6j39", "eprint_id": 95884, "eprint_status": "archive", "datestamp": "2023-08-21 23:29:59", "lastmod": "2024-01-14 21:45:06", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Single Pulse Response of a Plasma", "ispublished": "unpub", "full_text_status": "public", "keywords": "Coherent cyclotron radiation; plasma emission; pulse response of a plasma", "note": "The author acknowledges with pleasure numerous discussions with Dr. Wilhelm Kegel on this subject, and the support of the Office of Naval Research for research in this area.\n\nAccepted Version - TR000371.pdf
", "abstract": "The conjecture by Hirschfield and Wachtel that a weak pulse of radiation can trigger the emission of a large delayed burst of coherent electron cyclotron radiation is examined critically. The effect is found to exist when the electrons have a single velocity perpendicular to the magnetic field, but disappears in a thermal equilibrium distribution.", "date": "2019-05-29", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20190529-144700394", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190529-144700394", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" } ] }, "other_numbering_system": { "items": [ { "id": "31", "name": "Electron Tube and Microwave Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.7907/BERK-CG34", "primary_object": { "basename": "TR000371.pdf", "url": "https://authors.library.caltech.edu/records/298gp-e6j39/files/TR000371.pdf" }, "resource_type": "monograph", "pub_year": "2019", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/n8f2y-0zw68", "eprint_id": 94407, "eprint_status": "archive", "datestamp": "2023-08-19 07:12:39", "lastmod": "2024-01-14 21:41:38", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "Yariv-A", "name": { "family": "Yariv", "given": "A." } }, { "id": "Harp-R-S", "name": { "family": "Harp", "given": "R. S." } } ] }, "title": "Final Review Report to U.S. Office of Naval Research from California Institute of Technology", "ispublished": "unpub", "full_text_status": "public", "note": "Submitted - TR000381.pdf
", "abstract": "This report covers briefly the research performed under Contract Nonr 220(50) between September 1, 1963 and September 1, 1969. This con- tract was a continuation of a previous contract, Nonr 220(13), and in some cases carried through without interruption projects begun under the former contract. Equipment used under the former contract was continued under Nonr 220(50).\n\nThe research was both theoretical and experimental and generally covered the following areas:\n\nPlasma wave resonances in spatially non-uniform plasmas\nCyclotron and upper hybrid echo phenomena in plasmas\nPlasma wave echoes\nCyclotron harmonic waves in plasmas\nResonance cones in anisotropic plasmas\nRecombination radiation from forward biased p-n junctions\nElectro-optic effect\nInfrared absorption in gallium arsenide\nModes in optical resonators with gain \n\nThe results of the research were circulated in the form of O.N.R. Technical Reports and published articles in technical journals, lists of which appear in Sections III and IV of this report.", "date": "2019-04-03", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20190403-122912149", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190403-122912149", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.7907/AHH4-0607", "primary_object": { "basename": "TR000381.pdf", "url": "https://authors.library.caltech.edu/records/n8f2y-0zw68/files/TR000381.pdf" }, "resource_type": "monograph", "pub_year": "2019", "author_list": "Gould, R. W.; Yariv, A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/80r3a-gb642", "eprint_id": 94318, "eprint_status": "archive", "datestamp": "2023-08-21 23:36:57", "lastmod": "2024-01-14 21:41:19", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Echoes in Collision-Free Plasmas", "ispublished": "unpub", "full_text_status": "public", "keywords": "Plasma waves; echo; collisionless damping", "note": "Accepted Version - TR000376.pdf
", "abstract": "It is shown that temporal echoes can occur in collision-free plasmas at various times for different wave number combinations and that spatial echoes can occur at various positions for different frequency combinations.", "date": "2019-04-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20190401-115545626", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190401-115545626", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" } ] }, "other_numbering_system": { "items": [ { "id": "36", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.7907/ST3E-KR46", "primary_object": { "basename": "TR000376.pdf", "url": "https://authors.library.caltech.edu/records/80r3a-gb642/files/TR000376.pdf" }, "resource_type": "monograph", "pub_year": "2019", "author_list": "Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/0kbzg-wxz03", "eprint_id": 94331, "eprint_status": "archive", "datestamp": "2023-08-21 23:39:40", "lastmod": "2024-01-14 21:41:21", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bauer-Luc-O-E", "name": { "family": "Bauer", "given": "L. O." } }, { "id": "Blum-F-A", "name": { "family": "Blum", "given": "F. A." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Plasma Echoes at Upper Hybrid Resonance", "ispublished": "unpub", "full_text_status": "public", "keywords": "Plasma scattering; upper hybrid resonance; cyclotron echo", "note": "Submitted - TR000377.pdf
", "abstract": "Experimental observation of a new plasma echo at upper hybrid resonance is reported and a simple theoretical model which exhibits some major features of the results is presented.", "date": "2019-04-01", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20190401-141208583", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190401-141208583", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" } ] }, "other_numbering_system": { "items": [ { "id": "37", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.7907/D7WH-MQ20", "primary_object": { "basename": "TR000377.pdf", "url": "https://authors.library.caltech.edu/records/0kbzg-wxz03/files/TR000377.pdf" }, "resource_type": "monograph", "pub_year": "2019", "author_list": "Bauer, L. O.; Blum, F. A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/e8vw4-xar23", "eprint_id": 94163, "eprint_status": "archive", "datestamp": "2023-08-19 05:12:24", "lastmod": "2024-01-14 21:40:41", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Cyclotron Echo Phenomena", "ispublished": "unpub", "full_text_status": "public", "note": "I would like to acknowledge very fruitful discussions with W. K. Kegel, R. M. Hill, D. E. Kaplan and J. L. Hirschfield.\n\nAccepted Version - TR000368.pdf
Submitted - TR000368.txt
", "abstract": "[no abstract]", "date": "2019-03-27", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20190326-181930794", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190326-181930794", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" } ] }, "other_numbering_system": { "items": [ { "id": "28", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.7907/E6PJ-RM56", "primary_object": { "basename": "TR000368.pdf", "url": "https://authors.library.caltech.edu/records/e8vw4-xar23/files/TR000368.pdf" }, "related_objects": [ { "basename": "TR000368.txt", "url": "https://authors.library.caltech.edu/records/e8vw4-xar23/files/TR000368.txt" } ], "resource_type": "monograph", "pub_year": "2019", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/01v2g-bdd54", "eprint_id": 93180, "eprint_status": "archive", "datestamp": "2023-08-19 03:07:53", "lastmod": "2024-01-14 21:35:07", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Traveling Wave Couplers for Longitudinal Beam Type Amplifiers", "ispublished": "unpub", "full_text_status": "public", "note": "The author wishes to express his sincere appreciation to Mr. D. C. Forster for several illuminating discussions of this problem and to Mr. K. Hebert for writing the program for machine computation of the matrix elements. Support for research on microwave electronics by the Office of Naval Research and for the investigation reported here by the Sperry Rand Corporation is gratefully acknowledged.\n\nAccepted Version - TR000348.pdf
", "abstract": "The equations governing traveling wave interaction between an electron beam and a slow wave circuit are formulated in terms of amplitudes of circuit mode and slow and fast space charge modes. The resulting equations are solved to find expressions for the matrix which relates the mode amplitudes at the output of the traveling wave coupler to the mode amplitudes at the input. The properties of this matrix are discussed and numerical values given for Kompfner Dip. \n\nMatrices for velocity jumps and drift regions are also given and the characteristics of couplers which are preceded by or followed by a drift region and velocity jump are discussed. \n\nIt is shown that necessary and sufficient conditions for the removal of beam noise from the fast space charge wave by any lossless coupler are that, for a circuit input, there be no circuit output (M\u2081\u2081 = 0) and no slow space charge wave output (M\u2082\u2081 = 0). \n\nThese results are then applied to the design of fast space charge wave couplers for longitudinal beam type parametric amplifiers.", "date": "2019-02-25", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20190222-101242334", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190222-101242334", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(13)" }, { "agency": "Sperry Rand Corporation" } ] }, "other_numbering_system": { "items": [ { "id": "8", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.7907/CSE6-5H40", "primary_object": { "basename": "TR000348.pdf", "url": "https://authors.library.caltech.edu/records/01v2g-bdd54/files/TR000348.pdf" }, "resource_type": "monograph", "pub_year": "2019", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/z6e4w-tnr19", "eprint_id": 92963, "eprint_status": "archive", "datestamp": "2023-08-19 02:39:06", "lastmod": "2024-01-14 21:28:55", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Plasma Oscillations and Radio Noise from the Disturbed Sun", "ispublished": "unpub", "full_text_status": "public", "note": "I wish to thank my associates with whom various aspects of this problem have been discussed and particularly Professor Lester M. Field for his continued interest in this investigation. My stay at the California Institute of Technology has been made possible through the financial support of the National Science Foundation and the Hughes Aircraft Company. Assistance with computation and preparation of the manuscript from Mr. Iwao Sugai; my wife, Bunny; and Mrs. Ruth Brown is gratefully acknowledged.\n\nAccepted Version - TR000344.pdf
", "abstract": "Many investigators have suggested that plasma oscillations in the solar corona may be the source of large bursts of radio noise in the meter wavelength region. Two aspects of this problem are considered in this report: (a) the excitation of plasma oscillations by directed beams of charged particles, and (b) the conversion of energy in the longitudinal plasma oscillations to transverse electromagnetic waves by means of random inhomogeneities in electron density.\n\nIt appears unlikely that charged particles whose velocity is much less than the r.m.s. thermal velocity of the coronal electrons will excite plasma oscillations. Charged particles whose velocity is much greater than the r.m.s. thermal velocity excite oscillations in a band of frequencies, including frequencies above the local plasma frequency. However, qualitative arguments indicate that the noise should be concentrated in a narrow band of frequencies slightly below the local plasma frequency. Thus it is impossible to explain the Type II (slow) bursts in the manner assumed and unlikely that the Type III (fast) bursts are explainable in this manner. The transfer of energy is studied in detail and it is shown that only waves whose phase velocity is less than the directed beam of charged particles receive energy from the beam. \n\nIt is shown that plasma oscillations radiate a small fraction of their energy if the electron density is not uniform. In particular, random fluctuations in density, of the amount expected in thermal equilibrium, cause about 10-5 of the plasma-oscillation energy to be radiated; the remainder is dissipated by short-range collisions. Larger fluctuations than this are likely, and hence more energy should be radiated.", "date": "2019-02-19", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20190215-162437265", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190215-162437265", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(13)" }, { "agency": "NSF" }, { "agency": "Hughes Aircraft Company" } ] }, "other_numbering_system": { "items": [ { "id": "4", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.7907/NCH1-CH46", "primary_object": { "basename": "TR000344.pdf", "url": "https://authors.library.caltech.edu/records/z6e4w-tnr19/files/TR000344.pdf" }, "resource_type": "monograph", "pub_year": "2019", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9fy9q-ckk31", "eprint_id": 92937, "eprint_status": "archive", "datestamp": "2023-08-19 02:37:01", "lastmod": "2024-01-14 21:28:51", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "A Field Analysis of the M-Type Backward Wave Oscillator", "ispublished": "unpub", "full_text_status": "public", "note": "I wish to thank my associates with whom various aspects of this problem have been discussed and particularly Professor Lester M. Field for his continued interest in this investigation. My stay at the California Institute of Technology has been made possible through the financial support of the National Science Foundation and the Hughes Air craft Company. Assistance with computation and preparation of the manuscript from Mr. Iwao Sugai; my wife, Bunny; and Mrs. Ruth Brown, is gratefully acknowledged.\n\nSubmitted - TR000343.pdf
", "abstract": "A field theory of electron beams focused by crossed electric and magnetic fields is given. The theory is basic to the understanding of the small signal behavior of crossed field electron devices. It is applied to explain the slipping stream, or diocotron, effect as a coupling of two surface waves of the electron beam, and to derive the start oscillation conditions of the M-type backward wave oscillator. It is found that the slipping stream effect can reduce the starting current by an appreciable factor. The results are compared with the thin beam theory which neglects space charge effects. \n\nAn analysis of a loaded strip transmission line is given, from which a method of representing space harmonic slow wave circuits by a surface admittance boundary condition is obtained. Forward and backward space harmonic interaction may be treated equally well.", "date": "2019-02-14", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20190214-113127767", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190214-113127767", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(13)" }, { "agency": "Sperry Gyroscope Company" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.7907/GQK7-PH31", "primary_object": { "basename": "TR000343.pdf", "url": "https://authors.library.caltech.edu/records/9fy9q-ckk31/files/TR000343.pdf" }, "resource_type": "monograph", "pub_year": "2019", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8c7ch-4qx79", "eprint_id": 92832, "eprint_status": "archive", "datestamp": "2023-08-19 02:31:26", "lastmod": "2024-01-14 21:28:37", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Interaction of an Electron Beam with a Periodic Circuit", "ispublished": "unpub", "full_text_status": "public", "note": "Accepted Version - TR000341.pdf
", "abstract": "A field theory of a space-harmonic traveling wave tube is developed using a stationary field matching procedure. The circuit is the circularly symmetric disc loaded waveguide. Two cases are studied: a solid low current electron beam which completely fills the openings between sections, and a hollow beam of arbitrary radius. The latter analysis can be extended to the solid beam case through the use of Fletcher's equivalent hollow beam method. \n\nParticular attention is paid to the difference between forward space harmonics and backward space harmonics, and a comparison is made with Pierce's traveling wave tube parameters K and Q for both types of space harmonics. One result is to show that the sign of K is negative for back- ward space harmonics, while the sign of QC is positive. The principle value of the work may be in its use in \"admittance-wall\" or complete field theory analyses of forward and backward wave devices.", "date": "2019-02-13", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20190211-113513092", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190211-113513092", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(13)" } ] }, "collection": "CaltechAUTHORS", "other_numbering_system": { "items": [ { "id": "1", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory", "value": "Electron Tube and Microwave Laboratory" } ] }, "doi": "10.7907/MVWD-C702", "primary_object": { "basename": "TR000341.pdf", "url": "https://authors.library.caltech.edu/records/8c7ch-4qx79/files/TR000341.pdf" }, "resource_type": "monograph", "pub_year": "2019", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4m8gb-sm103", "eprint_id": 28552, "eprint_status": "archive", "datestamp": "2023-08-19 08:14:44", "lastmod": "2023-10-24 17:58:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Anderson-M-W", "name": { "family": "Anderson", "given": "M. W." } }, { "id": "O'Neil-T-M", "name": { "family": "O'Neil", "given": "T. M." } }, { "id": "Dubin-D-H-E", "name": { "family": "Dubin", "given": "D. H. E." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Degenerate mixing of plasma waves on cold, magnetized single-species plasmas", "ispublished": "pub", "full_text_status": "public", "keywords": "damping, dispersion relations, mixing, numerical analysis, perturbation techniques, plasma instability, plasma magnetohydrodynamic waves, viscosity", "note": "\u00a9 2011 American Institute of Physics. \n\nReceived 3 June 2011; accepted 12 September 2011; published online 24 October 2011. \n\nThe authors wish to thank Matthew Affolter, Francois Anderegg, Fred Driscoll, and Ross Spencer for many useful discussions. This research was supported by grants from NSF (No. PHY-0903877) and DOE (No. DE-SC0002451).\n\nPublished - PhysPlasmas_18_102113.pdf
", "abstract": "In the cold-fluid dispersion relation \u03c9 = \u03c9_p/[1+(k_\u22a5/k_z)^(2]1/2) for Trivelpiece-Gould waves on an infinitely long magnetized plasma cylinder, the transverse and axial wavenumbers appear only in the combination k_\u22a5/k_z. As a result, for any frequency \u03c9<\u03c9_p, there are infinitely many degenerate waves, all having the same value of k_\u22a5/k_z. On a cold finite-length plasma column, these degenerate waves reflect into one another at the ends; thus, each standing-wave normal mode of the bounded plasma is a mixture of many degenerate waves, not a single standing wave as is often assumed. A striking feature of the many-wave modes is that the short-wavelength waves often add constructively along resonance cones given by dz/dr = \u00b1(\u03c9_p^2/\u03c9^2-1)^(1/2). Also, the presence of short wavelengths in the admixture for a predominantly long-wavelength mode enhances the viscous damping beyond what the single-wave approximation would predict. Here, numerical solutions are obtained for modes of a cylindrical plasma column with rounded ends. Exploiting the fact that the modes of a spheroidal plasma are known analytically (the Dubin modes), a perturbation analysis is used to investigate the mixing of low-order, nearly degenerate Dubin modes caused by small deformations of a plasma spheroid.", "date": "2011-10", "date_type": "published", "publication": "Physics of Plasmas", "volume": "18", "number": "10", "publisher": "American Institute of Physics", "pagerange": "Art. No. 102113", "id_number": "CaltechAUTHORS:20111221-134324531", "issn": "1070-664X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20111221-134324531", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-0903877" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0002451" } ] }, "doi": "10.1063/1.3646922", "primary_object": { "basename": "PhysPlasmas_18_102113.pdf", "url": "https://authors.library.caltech.edu/records/4m8gb-sm103/files/PhysPlasmas_18_102113.pdf" }, "resource_type": "article", "pub_year": "2011", "author_list": "Anderson, M. W.; O'Neil, T. M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/430cz-k0q87", "eprint_id": 3934, "eprint_status": "archive", "datestamp": "2023-08-22 05:02:47", "lastmod": "2023-10-16 16:13:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shiga-Nobuyasu", "name": { "family": "Shiga", "given": "N." } }, { "id": "Anderegg-Francois", "name": { "family": "Anderegg", "given": "F." } }, { "id": "Dubin-Daniel-H-E", "name": { "family": "Dubin", "given": "D. H. E." } }, { "id": "Driscoll-C-Fred", "name": { "family": "Driscoll", "given": "C. F." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Thermally excited fluctuations as a pure electron plasma temperature diagnostic", "ispublished": "pub", "full_text_status": "public", "keywords": "plasma fluctuations; plasma temperature; plasma diagnostics; plasma instability; antennas in plasma; plasma thermodynamics", "note": "\u00a9 2006 American Institute of Physics. \n\nReceived 16 November 2005; accepted 18 January 2006; published online 16 February 2006. \n\nWe thank Professor R. E. Pollock for his seminal contributions and Professor T. M. O'Neil and Dr. J. Danielson for many fruitful discussions. This work was supported by National Science Foundation Grant No. PHY-0354979.\n\nPublished - SHIpop06.pdf
", "abstract": "Thermally excited charge fluctuations in pure electron plasma columns provide a diagnostic for the plasma temperature over a range of 0.05 < k(B)T < 10 eV. Three different nonperturbative methods have been developed to determine the plasma temperature. The first method fits the near-Lorentzian spectrum of thermal fluctuations near a single weakly damped mode. This method works well where the modes are weakly damped, i.e., when lambda(D)/R-p < 0.3. The second method utilizes the emission spectrum over a broad frequency range encompassing several modes and the nonresonant fluctuations between modes. This method works for long columns with lambda(D)/R-p > 0.2, so that Landau damping is dominant and well modeled by theory. The third method compares the total (frequency-integrated) number delta N of fluctuating image charges on the wall antenna to a simple thermodynamic calculation. This method works when lambda(D)/R-p > 0.2.", "date": "2006-02", "date_type": "published", "publication": "Physics of Plasmas", "volume": "13", "number": "2", "publisher": "American Institute of Physics", "pagerange": "Art. No. 022109", "id_number": "CaltechAUTHORS:SHIpop06", "issn": "1070-664X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:SHIpop06", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-0354979" } ] }, "doi": "10.1063/1.2172928", "primary_object": { "basename": "SHIpop06.pdf", "url": "https://authors.library.caltech.edu/records/430cz-k0q87/files/SHIpop06.pdf" }, "resource_type": "article", "pub_year": "2006", "author_list": "Shiga, N.; Anderegg, F.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/jx7cc-h4492", "eprint_id": 1810, "eprint_status": "archive", "datestamp": "2023-08-22 01:09:29", "lastmod": "2024-01-11 23:24:47", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Thermal Fluctuations: Modes versus the Continuum", "ispublished": "unpub", "full_text_status": "public", "keywords": "electrons; plasma fluctuations; spectral analysis; vibrational modes; velocity; magnetic fields; axial symmetry", "note": "\u00a9 2003 American Institute of Physics \n\nThe author is grateful to N. Shiga, F. Anderegg, and other members of the U.C.S.D. group for stimulating discussions of their results.\n\nPublished - GOUaipcp03.pdf
", "abstract": "The thermal fluctuation spectrum of the signal received on a patch electrode is examined and it is shown that the spectrum shows both the modes of the plasma and a continuous spectrum related to the independent-particle motions of plasma electrons. Modes whose axial phase velocity are more than 3\u20134 times the electron thermal speed are lightly Landau-damped and are clearly separated from the continuum. Long wavelength modes are \"acoustic\" in nature. If the axial phase velocity of a mode becomes less than 1\u20132 times the electron thermal speed, then the mode becomes strongly Landau-damped and it merges into the continuum. The mode velocities are of the order of wpa , where a is the plasma radius, so that the plasma radius must be at least several deBye lengths in order to have lightly damped modes. In general, the spectrum is a mixture of a continuous spectrum together with a finite number of modes which are Landau-damped by varying amounts, depending on their phase velocity relative to the electron thermal speed. Only in the extreme limit, wpa << vth does the continuous spectrum tend to a Gaussian of width k vth, characteristic of independent particles. The effect of the \"load impedance\" on the measurements is also discussed.", "date": "2003-12", "date_type": "published", "publisher": "American Institute of Physics", "place_of_pub": "Melville, N.Y.", "pagerange": "15-21", "id_number": "CaltechAUTHORS:GOUaipcp03", "isbn": "9780735401655", "book_title": "Non-neutral plasma physics V : Workshop on Non-Neutral Plasmas : Santa Fe, New Mexico, 7-11 July 2003", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GOUaipcp03", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "contributors": { "items": [ { "id": "Schauer-Martin", "name": { "family": "Schauer", "given": "Martin" } }, { "id": "Mitchell-Travis", "name": { "family": "Mitchell", "given": "Travis" } }, { "id": "Nebel-Richard", "name": { "family": "Nebel", "given": "Richard" } } ] }, "doi": "10.1063/1.1635152", "primary_object": { "basename": "GOUaipcp03.pdf", "url": "https://authors.library.caltech.edu/records/jx7cc-h4492/files/GOUaipcp03.pdf" }, "resource_type": "book_section", "pub_year": "2003", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qx2m7-wwy14", "eprint_id": 1672, "eprint_status": "archive", "datestamp": "2023-08-22 00:25:52", "lastmod": "2023-10-13 22:56:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Anderegg-Francois", "name": { "family": "Anderegg", "given": "F." } }, { "id": "Shiga-Nobuyasu", "name": { "family": "Shiga", "given": "N." } }, { "id": "Dubin-Daniel-H-E", "name": { "family": "Dubin", "given": "D. H. E." } }, { "id": "Driscoll-C-Fred", "name": { "family": "Driscoll", "given": "C. F." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Thermally excited Trivelpiece\u2013Gould modes as a pure electron plasma temperature diagnostic", "ispublished": "pub", "full_text_status": "public", "keywords": "NONNEUTRAL PLASMAS; COLD ANTIHYDROGEN; TRANSPORT; CONFINEMENT; VIBRATIONS", "note": "\u00a9 2003 American Institute of Physics. \n\nReceived 11 November 2002; accepted 19 December 2002. \n\nWe thank Dr. R. E. Pollock for his seminal contributions and Dr. T. M. O'Neil for many fruitful discussions. This work is supported by Office of Naval Research Grant No. N00014-96-1-0239 and National Science Foundation Grant No. PHY-9876999.\n\nPublished - ANDpop03.pdf
", "abstract": "Thermally excited plasma modes are observed in trapped, near-thermal-equilibrium pure electron plasmas over a temperature range of 0.05 < kT < 5 eV. The modes are excited and damped by thermal fluctuations in both the plasma and the receiver electronics. The thermal emission spectra together with a plasma-antenna coupling coefficient calibration uniquely determine the plasma (and load) temperature. This calibration is obtained from the mode spectra themselves when the receiver-generated noise absorption is measurable; or from separate wave reflection/absorption measurements; or from kinetic theory. This nondestructive temperature diagnostic agrees well with standard diagnostics, and may be useful for expensive species such as antimatter.", "date": "2003-05", "date_type": "published", "publication": "Physics of Plasmas", "volume": "10", "number": "5", "publisher": "American Institute of Physics", "pagerange": "1556-1562", "id_number": "CaltechAUTHORS:ANDpop03", "issn": "1070-664X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:ANDpop03", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-96-1-0239" }, { "agency": "NSF", "grant_number": "PHY-9876999" } ] }, "doi": "10.1063/1.1559973", "primary_object": { "basename": "ANDpop03.pdf", "url": "https://authors.library.caltech.edu/records/qx2m7-wwy14/files/ANDpop03.pdf" }, "resource_type": "article", "pub_year": "2003", "author_list": "Anderegg, F.; Shiga, N.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rb7cs-k1e89", "eprint_id": 1987, "eprint_status": "archive", "datestamp": "2023-08-22 00:19:29", "lastmod": "2023-10-13 23:07:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Anderegg-Francois", "name": { "family": "Anderegg", "given": "F." } }, { "id": "Shiga-Nobuyasu", "name": { "family": "Shiga", "given": "N." } }, { "id": "Danielson-James-R", "name": { "family": "Danielson", "given": "J. R." } }, { "id": "Dubin-Daniel-H-E", "name": { "family": "Dubin", "given": "D. H. E." } }, { "id": "Driscoll-C-Fred", "name": { "family": "Driscoll", "given": "C. F." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Thermally Excited Modes in a Pure Electron Plasma", "ispublished": "pub", "full_text_status": "public", "keywords": "electron gas; heat radiation; plasma diagnostics; plasma density; plasma temperature; thermal noise; spectral analysis", "note": "\u00a9 2003 The American Physical Society \n\n(Received 3 December 2001; published 17 March 2003) \n\nThis work is supported by ONR Grant No. N00014-96-1-0239 and NSF Grant No. PHY-9876999. We thank R. E. Pollock and T.M. O'Neil for many fruitful discussions.\n\nPublished - ANDprl03.pdf
", "abstract": "Thermally excited plasma modes are observed in near-thermal-equilibrium pure electron plasmas over a temperature range of 0.05", "date": "2003-03-21", "date_type": "published", "publication": "Physical Review Letters", "volume": "90", "number": "11", "publisher": "American Physical Society", "pagerange": "Art. No. 115001", "id_number": "CaltechAUTHORS:ANDprl03", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:ANDprl03", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-96-1-0239" }, { "agency": "NSF", "grant_number": "PHY-9876999" } ] }, "doi": "10.1103/PhysRevLett.90.115001", "primary_object": { "basename": "ANDprl03.pdf", "url": "https://authors.library.caltech.edu/records/rb7cs-k1e89/files/ANDprl03.pdf" }, "resource_type": "article", "pub_year": "2003", "author_list": "Anderegg, F.; Shiga, N.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/q0c13-gcd06", "eprint_id": 1808, "eprint_status": "archive", "datestamp": "2023-08-21 22:59:05", "lastmod": "2024-01-11 23:04:08", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Anderegg-Francois", "name": { "family": "Anderegg", "given": "Francois" } }, { "id": "Shiga-Nobuyasu", "name": { "family": "Shiga", "given": "Nobuyasu" } }, { "id": "Danielson-James-R", "name": { "family": "Danielson", "given": "James R." } }, { "id": "Dubin-Daniel-H-E", "name": { "family": "Dubin", "given": "Daniel H. E." } }, { "id": "Driscoll-C-Fred", "name": { "family": "Driscoll", "given": "C. Fred" } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Thermal excitation of Trivelpiece-Gould modes in a pure electron plasma", "ispublished": "unpub", "full_text_status": "public", "keywords": "electron traps; plasma properties; excited states; plasma waves; plasma temperature; temperature measurement", "note": "\u00a9 2002 American Institute of Physics. \n\nThis work is supported by Office of Naval Research Grant No. N00014-96-1-0239 and National Science Foundation Grant PHY-9876999. We thank Dr. R.E. Pollock for suggesting this work and demonstrating that thermally excited TG modes can be observed; and Dr. T.M. O'Neil for many fruitful discussions.\n\nPublished - ANDaipcp02.pdf
", "abstract": "Thermally excited plasma modes are observed in trapped, near-thermal-equilibrium pure electron plasmas over a temperature range of 0.05 < T < 5 eV. The measured thermal emission spectra together with a separate measurement of the wave absorption coefficient uniquely determines the temperature. Alternately, kinetic theory including the antenna geometry and the measured mode damping (i.e. spectral width) gives the plasma impedance, obviating the reflection measurement. This non-destructive temperature diagnostic agrees well with standard diagnostics, and may be useful for expensive species such as anti-matter.", "date": "2002-02", "date_type": "published", "publisher": "American Institute of Physics", "place_of_pub": "Melville, NY", "pagerange": "253-262", "id_number": "CaltechAUTHORS:ANDaipcp02", "isbn": "0735400504", "book_title": "Non-Neutral Plasma Physics IV", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:ANDaipcp02", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-96-1-0239" }, { "agency": "NSF", "grant_number": "PHY-9876999" } ] }, "contributors": { "items": [ { "id": "Anderegg-Francois", "name": { "family": "Anderegg", "given": "Francois" } }, { "id": "Driscoll-C-Fred", "name": { "family": "Driscoll", "given": "C. Fred" } }, { "id": "Schweikhard-Lutz", "name": { "family": "Schweikhard", "given": "Lutz" } } ] }, "doi": "10.1063/1.1454291", "primary_object": { "basename": "ANDaipcp02.pdf", "url": "https://authors.library.caltech.edu/records/q0c13-gcd06/files/ANDaipcp02.pdf" }, "resource_type": "book_section", "pub_year": "2002", "author_list": "Anderegg, Francois; Shiga, Nobuyasu; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/jjv8s-knq62", "eprint_id": 1809, "eprint_status": "archive", "datestamp": "2023-08-21 22:59:09", "lastmod": "2024-01-11 23:04:10", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Thermal excitation of modes in a non-neutral plasma", "ispublished": "unpub", "full_text_status": "public", "keywords": "plasma fluctuations; thermal noise; Nyquist stability; plasma waves; excited states; electron traps; plasma temperature", "note": "\u00a9 2002 American Institute of Physics. \n\nThe author is grateful to F. Anderegg for communicating the experimental results and to members of the U.C.S.D group for stimulating discussions.\n\nPublished - GOUaipcp02.pdf
", "abstract": "We examine theoretically the thermal fluctuations in a non-neutral plasma, as observed on a segmented electrode surrounding the plasma, using the Nyquist theorem. The fluctuation spectrum is peaked at frequencies which correspond to modes of the plasma. Measurement of these fluctuations and of the input admittance of the plasma in the vicinity of one of the mode resonances can be used to give a completely experimental, and non-destructive, measurement of the plasma temperature. Since some of the modes are negative energy modes and exhibit negative absorption due to the plasma rotation, a direct application of the Nyquist theorems will not give correct results for the non-axisymmetric modes. This problem is circumvented by first calculating the fluctuations in a frame rotating with the plasma and transforming to the laboratory frame. This results in a modification of Nyquist's theorem. Measurement issues are discussed.", "date": "2002-02", "date_type": "published", "publisher": "American Institute of Physics", "pagerange": "263-270", "id_number": "CaltechAUTHORS:GOUaipcp02", "isbn": "0735400504", "book_title": "Non-Neutral Plasma Physics IV", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GOUaipcp02", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "contributors": { "items": [ { "id": "Anderegg-Francois", "name": { "family": "Anderegg", "given": "Francois" } }, { "id": "Driscoll-C-Fred", "name": { "family": "Driscoll", "given": "C. Fred" } }, { "id": "Schweikhard-Lutz", "name": { "family": "Schweikhard", "given": "Lutz" } } ] }, "doi": "10.1063/1.1454292", "primary_object": { "basename": "GOUaipcp02.pdf", "url": "https://authors.library.caltech.edu/records/jjv8s-knq62/files/GOUaipcp02.pdf" }, "resource_type": "book_section", "pub_year": "2002", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/fx7ej-9ea17", "eprint_id": 121847, "eprint_status": "archive", "datestamp": "2023-08-19 04:36:02", "lastmod": "2024-01-16 01:06:35", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Wave angular momentum in nonneutral plasmas", "ispublished": "unpub", "full_text_status": "public", "note": "\u00a9 1999 American Institute of Physics. \n\nResearch Sponsored by the U. S. Office of Naval Research.\n\nPublished - 170_1_online.pdf
", "abstract": "Angular momentum and energy are added (or removed) when exciting a mode, such as a diocotron, Trivelpiece-Gould, or Dubin mode, and we discuss rates at which mode angular momentum and energy are added by applied fields. Excitation of a plasma mode is an effective way to transfer angular momentum and energy to the plasma because it is a resonant process. We relate this to recent experiments on compression and expansion of plasmas using a \"rotating wall\" field. We also calculate the torque on a Coulomb crystal which is phase-locked to a \"rotating wall\" field and describe phase oscillations and the maximum rate of acceleration which can be achieved.", "date": "1999-08", "date_type": "published", "publisher": "American Institute of Physics", "place_of_pub": "Melville, NY", "pagerange": "170-175", "id_number": "CaltechAUTHORS:20230612-708648000.25", "isbn": "9781563969133", "book_title": "Non-neutral plasma physics III", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230612-708648000.25", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" } ] }, "doi": "10.1063/1.1302116", "primary_object": { "basename": "170_1_online.pdf", "url": "https://authors.library.caltech.edu/records/fx7ej-9ea17/files/170_1_online.pdf" }, "resource_type": "book_section", "pub_year": "1999", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/604x8-6s447", "eprint_id": 9814, "eprint_status": "archive", "datestamp": "2023-08-22 10:50:20", "lastmod": "2023-10-16 22:30:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bachman-David-A", "name": { "family": "Bachman", "given": "David A." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Landau-like damping in rotating pure electron plasmas", "ispublished": "pub", "full_text_status": "public", "keywords": "plasma flow; Landau-like damping; differential rotation; externally applied pulse; nondissipative decay process; numerical solution; perturbed density; rotating pure electron plasmas; two-dimensional linearized incompressible fluid equations", "note": "\u00a9 1996 IEEE. Reprinted with permission. \n\nManuscript received July 14, 1995; revised October 3, 1995. \n\nThis work was supported by the Office of Naval Research.\n\nPublished - BACieeetps96.pdf
", "abstract": "A numerical solution of the two-dimensional (2-D) linearized incompressible fluid equations has been used to study the response of a cylindrical pure electron plasma to an externally applied pulse. The plasma response to the pulse exhibits a nondissipative decay process. This decay is due to differential rotation of the plasma at different radii and is clearly shown by computer-generated displays of the perturbed density.", "date": "1996-02", "date_type": "published", "publication": "IEEE Transactions on Plasma Science", "volume": "24", "number": "1", "publisher": "IEEE", "pagerange": "14-15", "id_number": "CaltechAUTHORS:BACieeetps96", "issn": "0093-3813", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:BACieeetps96", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" } ] }, "doi": "10.1109/27.491667", "primary_object": { "basename": "BACieeetps96.pdf", "url": "https://authors.library.caltech.edu/records/604x8-6s447/files/BACieeetps96.pdf" }, "resource_type": "article", "pub_year": "1996", "author_list": "Bachman, David A. and Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dhsmm-vf981", "eprint_id": 1684, "eprint_status": "archive", "datestamp": "2023-08-22 10:27:17", "lastmod": "2023-10-13 22:56:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Dynamics of non-neutral plasmas", "ispublished": "pub", "full_text_status": "public", "keywords": "PLASMA INSTABILITY; VORTEX FLOW; CYLINDRICAL CONFIGURATION; BERNSTEIN MODE; ELECTRON GAS; TEMPERATURE MEASUREMENT; CHARGED PARTICLES; BEAM DYNAMICS; TRANSPORT THEORY; PLASMA; DYNAMICS", "note": "\u00a91995 American Institute of Physics. \n\n(Received 14 November 1994; accepted 9 January 1995) \n\nI gratefully acknowledge the vital contributions of N. Sateesh Pillai and Michael A. LaPointe to the results, described in Sets. IV and VI, respectively. I am also deeply grateful to the late John H. Malmberg and Thomas M. O'Neil for rekindling my interest in this subject and, together with Fred Driscoll, for freely sharing their insights and expertise. \n\nI thank the Office of Naval Research for its support of the research reported here.\n\nPublished - GOUpop95b.pdf
", "abstract": "In this paper the focus is on the dynamics of two-dimensional cylindrical non-neutral plasmas. After reviewing some highlights of the non-neutral plasma dynamics, some recent two-dimensional results are described: vortex dynamics, diocotron instabilities of hollow profiles, collisionless damping of modes and fluid trapping by modes, fluid echoes, the cyclotron center of mass modes and warm plasma Bernstein modes, and temperature determination from fluctuation measurements. Attention is called to some unsolved problems.", "date": "1995-06", "date_type": "published", "publication": "Physics of Plasmas", "volume": "2", "number": "6", "publisher": "American Institute of Physics", "pagerange": "2151-2163", "id_number": "CaltechAUTHORS:GOUpop95b", "issn": "1070-664X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GOUpop95b", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" } ] }, "doi": "10.1063/1.871302", "primary_object": { "basename": "GOUpop95b.pdf", "url": "https://authors.library.caltech.edu/records/dhsmm-vf981/files/GOUpop95b.pdf" }, "resource_type": "article", "pub_year": "1995", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2zseh-qrn63", "eprint_id": 1685, "eprint_status": "archive", "datestamp": "2023-08-22 10:24:55", "lastmod": "2023-10-13 22:56:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Theory of cyclotron resonance in a cylindrical non-neutral plasma", "ispublished": "pub", "full_text_status": "public", "keywords": "CYCLOTRON RESONANCE; COLD PLASMA; BERNSTEIN MODE; ROTATING PLASMA; DOPPLER EFFECT; CYLINDRICAL CONFIGURATION; NON\u2013EQUILIBRIUM PLASMA; CORIOLIS FORCE", "note": "\u00a9 1995 American Institute of Physics. \n\n(Received 28 November 1994; accepted 22 December 1994) \n\nThe author is pleased to acknowledge E. Sarid for discussion of his experimental results and the Office of Naval Research for support of this work under Grant No. N000014-89-J-1264.\n\nPublished - GOUpop95a.pdf
", "abstract": "Resonances near the cyclotron frequency of a cylindrical non-neutral plasma column with radial density and angular velocity profiles are studied. Cold plasma and warm plasma models are used to consider the various multipole modes (eimtheta) for kz=0. For m=1 only a single resonance, a center of mass mode, is found. Its frequency is downshifted from the cyclotron frequency by an amount equal to the frequency of the low-frequency diocotron mode. For each m greater than 1 the cold plasma model gives a continuous absorption band with spatially localized absorption at each frequency, corresponding to a continuum of singular modes. In the warm plasma model, the continuuo go over to sets of discrete radially trapped azimuthally propagating Bernstein modes. For both cases, the plasma rotation Doppler-shifts the azimuthally propagating modes up in frequency. The angular velocity profile, together with plasma temperature, determine the spacing of the Bernstein modes within a band.", "date": "1995-05", "date_type": "published", "publication": "Physics of Plasmas", "volume": "2", "number": "5", "publisher": "American Institute of Physics", "pagerange": "1404-1411", "id_number": "CaltechAUTHORS:GOUpop95a", "issn": "1070-664X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GOUpop95a", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N000014-89-J-1264" } ] }, "doi": "10.1063/1.871356", "primary_object": { "basename": "GOUpop95a.pdf", "url": "https://authors.library.caltech.edu/records/2zseh-qrn63/files/GOUpop95a.pdf" }, "resource_type": "article", "pub_year": "1995", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3epnp-p5a44", "eprint_id": 1811, "eprint_status": "archive", "datestamp": "2023-08-22 10:07:54", "lastmod": "2023-10-13 23:01:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pillai-N-Sateesh", "name": { "family": "Pillai", "given": "N. Sateesh" } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Damping and Trapping in 2D Inviscid Fluids", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91994 The American Physical Society \n\nReceived 6 July 1993; revised 11 August 1994 \n\nThis work was supported by ONR Grant No. N00014-89-J-1264.\n\nPublished - PILprl94.pdf
", "abstract": "We demonstrate collisionless decay due to phase mixing of a disturbance in an inviscid 2D fluid with sheared flow. Experiments performed on a cylindrical pure electron plasma, which behaves as a 2D inviscid fluid, show that a small amplitude quadrupole excitation (m = 2, k = 0 mode) decays exponentially. At larger amplitudes, the exponential decay is modulated by bounce motion of fluid elements trapped in the azimuthally traveling wave field, with the bounce frequency proportional to the square root of the excitation amplitude. We also show that the linear decay rate is decreased by the addition of external dissipation. We describe a calculation of the linearized response function.", "date": "1994-11-21", "date_type": "published", "publication": "Physical Review Letters", "volume": "73", "number": "21", "publisher": "American Physical Society", "pagerange": "2849-2853", "id_number": "CaltechAUTHORS:PILprl94", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:PILprl94", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-89-J-1264" } ] }, "doi": "10.1103/PhysRevLett.73.2849", "primary_object": { "basename": "PILprl94.pdf", "url": "https://authors.library.caltech.edu/records/3epnp-p5a44/files/PILprl94.pdf" }, "resource_type": "article", "pub_year": "1994", "author_list": "Pillai, N. Sateesh and Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/aw137-jfn66", "eprint_id": 121851, "eprint_status": "archive", "datestamp": "2023-08-20 04:48:31", "lastmod": "2024-01-16 01:06:37", "type": "book_section", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moeller-Charles-P", "name": { "family": "Moeller", "given": "C. P." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "Phelps-D-A", "name": { "family": "Phelps", "given": "D. A." } }, { "id": "Pinsker-R-I", "name": { "family": "Pinsker", "given": "R. I." } } ] }, "title": "Combline antennas for launching traveling fast waves", "ispublished": "unpub", "full_text_status": "public", "note": "\u00a9 1994 American Institute of Physics.\n\nPublished - 323_1_online.pdf
", "abstract": "The combline structure shows promise for launching traveling fast magnetosonic waves with adjustable n\u2225 (3\u2264n\u2225\u22646) for current drive. In this paper, the dispersion and damping properties of the combine antenna with and without a Faraday shield are given. The addition of a Faraday shield which eliminates the electrostatic coupling between current straps as well as between the straps and plasma offers the advantage of eliminating the need for the lumped capacitors which are otherwise required with this structure. The results of vacuum dispersion and damping measurements on a low power model antenna are also given.", "date": "1994-10-15", "date_type": "published", "publisher": "American Institute of Physics", "id_number": "CaltechAUTHORS:20230612-708665000.32", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230612-708665000.32", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.44951", "primary_object": { "basename": "323_1_online.pdf", "url": "https://authors.library.caltech.edu/records/aw137-jfn66/files/323_1_online.pdf" }, "resource_type": "book_section", "pub_year": "1994", "author_list": "Moeller, C. P.; Gould, R. W.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ae5gt-xky75", "eprint_id": 60215, "eprint_status": "archive", "datestamp": "2023-08-20 04:34:28", "lastmod": "2023-10-20 23:14:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Barnes-Charles-A", "name": { "family": "Barnes", "given": "Charles A." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Robert V. Langmuir", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1994 AIP Publishing.\n\nPhysics Today\nLangmuir Obit Erratum\nCharles A. Barnes and Roy W. Gould \nPhysics Today 47 (11), 119 (1994); doi: 10.1063/1.2808723\n\nPublished - 1.2808621.pdf
Erratum - 1.2808723.pdf
", "abstract": "Robert V. Langmuir, professor emeritus of electrical engineering at Caltech and a member of the team that first directly observed synchrotron radiation, died of cancer on 7 May 1992, at the age of 80. Langmuir had had a long and productive career as an educator, physicist, engineer and inventor.", "date": "1994-08", "date_type": "published", "publication": "Physics Today", "volume": "47", "number": "8", "publisher": "American Institute of Physics", "pagerange": "75-76", "id_number": "CaltechAUTHORS:20150914-084848502", "issn": "0031-9228", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150914-084848502", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.2808621", "primary_object": { "basename": "1.2808621.pdf", "url": "https://authors.library.caltech.edu/records/ae5gt-xky75/files/1.2808621.pdf" }, "related_objects": [ { "basename": "1.2808723.pdf", "url": "https://authors.library.caltech.edu/records/ae5gt-xky75/files/1.2808723.pdf" } ], "resource_type": "article", "pub_year": "1994", "author_list": "Barnes, Charles A. and Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8dchs-4pa20", "eprint_id": 121848, "eprint_status": "archive", "datestamp": "2023-08-22 08:54:28", "lastmod": "2023-10-20 16:18:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } }, { "id": "LaPointe-Michael-A", "name": { "family": "LaPointe", "given": "Michael A." } } ] }, "title": "Cyclotron resonance phenomena in a pure electron plasma", "ispublished": "pub", "full_text_status": "public", "keywords": "Fluid Flow and Transfer Processes; General Physics and Astronomy; Mechanics of Materials; Condensed Matter Physics; Computational Mechanics", "note": "\u00a9 1992 American Institute of Physics. \n\nThe insights into the behavior of non-neutral plasmas of Fred Driscoll, John Malmberg, and Thomas O'Neil were very helpful in the early stages of this work. \n\nWe are pleased to acknowledge the support of the U.S. Office of Naval Research and the assistance of Sateesh Pillai in the conduct of this research.\n\nPublished - 2038_1_online.pdf
", "abstract": "An experiment designed to elucidate the features of cyclotron resonance in a rotating cylindrical pure electron plasma column is described. The density is well below the Brillouin limit and varies with radius, as does the rotational angular velocity. Thus the steady state is not the rigid\u2010rotor equilibrium which is frequently studied theoretically. The readily observed modes are found to have kz\u224a0 and m=1,2,3,4... (eikzz+im \u03b8) with frequencies which are within a few percent of the cyclotron frequency (140 MHz). A single m=1 mode is found that is downshifted from the cyclotron frequency by an amount equal to the m=1 diocotron frequency. For each of the higher m values, bands of closely spaced discrete modes are found which are upshifted from the cyclotron frequency by the Doppler effect of rotation. The bands of discrete modes are explained as radially trapped azimuthally propagating Bernstein modes in a rotating plasma and approximate theories for these modes are outlined. By comparing the results with experiments, plasma parameters such as the ratio of Larmor radius to plasma scale length, the central rotation frequency, and the ratio of peak to average density can be inferred.", "date": "1992-07", "date_type": "published", "publication": "Physics of Fluids B", "volume": "4", "number": "7", "publisher": "American Institute of Physics", "pagerange": "2038-2043", "id_number": "CaltechAUTHORS:20230612-708650000.26", "issn": "0899-8221", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230612-708650000.26", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" } ] }, "doi": "10.1063/1.860012", "primary_object": { "basename": "2038_1_online.pdf", "url": "https://authors.library.caltech.edu/records/8dchs-4pa20/files/2038_1_online.pdf" }, "resource_type": "article", "pub_year": "1992", "author_list": "Gould, Roy W. and LaPointe, Michael A." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6zf87-16b78", "eprint_id": 1682, "eprint_status": "archive", "datestamp": "2023-08-22 08:36:12", "lastmod": "2023-10-13 22:56:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } }, { "id": "LaPointe-Michael-A", "name": { "family": "LaPointe", "given": "Michael A." } } ] }, "title": "Cyclotron resonance in a pure electron plasma column", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1991 The American Physical Society \n\nReceived 16 September 1991 \n\nThis work was supported by ONR Grant No. N00014-89-J-1264 and one of us (R.W.G.) gratefully acknowledges stimulating discussions with C. F. Driscoll, J. H. Malmberg, and T. M. O'Neil about non-neutral plasmas.\n\nPublished - GOUprl91.pdf
", "abstract": "We demonstrate experimentally the effects of plasma rotation and particle thermal velocities on cyclotron resonance in a long cylindrical pure electron plasma column of low density (\u03c9\u209a\u00b2 \u226a \u03c9\ua700\u00b2). A single m=1 mode (e^(im\u03b8 - i\u03c9t)) is found whose frequency \u03c9 is down-shifted from \u03c9\ua700 = eB/m\u2091 by an amount equal to the low-frequency diocotron mode frequency (\u3008\u03c9p\u00b2\u3009/2\u03c9\ua700). For m = 2,3,4,. . . sets of modes are found which are Doppler shifted upward from \u03c9c. We explain these as radially trapped and azimuthally propagating Bernstein modes.", "date": "1991-12-23", "date_type": "published", "publication": "Physical Review Letters", "volume": "67", "number": "26", "publisher": "American Physical Society", "pagerange": "3685-3688", "id_number": "CaltechAUTHORS:GOUprl91", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GOUprl91", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-89-J-1264" } ] }, "doi": "10.1103/PhysRevLett.67.3685", "primary_object": { "basename": "GOUprl91.pdf", "url": "https://authors.library.caltech.edu/records/6zf87-16b78/files/GOUprl91.pdf" }, "resource_type": "article", "pub_year": "1991", "author_list": "Gould, Roy W. and LaPointe, Michael A." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3v531-d1k48", "eprint_id": 11538, "eprint_status": "archive", "datestamp": "2023-08-22 07:59:03", "lastmod": "2023-10-17 15:07:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Greene-Glenn-J", "name": { "family": "Greene", "given": "G. J." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Observation of wave-packet propagation in the ion cyclotron range of frequencies in a tokamak plasma", "ispublished": "pub", "full_text_status": "public", "keywords": "WAVE PACKETS, ICR HEATING, TOKAMAK DEVICES, PLASMA, HYDROGEN, DAMPING, ANTENNAS, MAGNETIC PROBES, AMPLITUDES, VELOCITY, PLASMA DENSITY, FREQUENCY DEPENDENCE, MAGNETIC FIELDS, TOROIDAL CONFIGURATION, CORRELATIONS, COLD PLASMA, GROUP VELOCITY", "note": "\u00a9 1991 American Institute of Physics. \n\nReceived 13 December 1989; accepted 3 August 1990. \n\nThis work was supported by the U. S. Department of Energy under Contracts No. DE-AS03-76-SFO-0767 and No. DE-AC02-76-CHO-3073.\n\nPublished - GREpofb91.pdf
", "abstract": "Experimental observation of wave-packet propagation in the ion cyclotron range of frequencies in a tokamak plasma is reported. Studies were carried out in the Caltech Research Tokamak [Phys. Fluids 23, 614 (1980)] in a pure hydrogen plasma and in a regime where fast-wave damping was sufficiently small to permit multiple toroidal transits of the wave packet. Waves were launched by exciting a small loop antenna with a short burst of radio-frequency current and were detected with shielded magnetic probes. Probe scans revealed a large increase in wave-packet amplitude at smaller minor radii, and the packet velocity was found to be independent of radial position. Measurement of the packet transit time yielded direct information about the wave group velocity. Packet velocity was investigated as a function of the fundamental excitation frequency, plasma density, and toroidal magnetic field. Results are compared with the predictions of a cold plasma model that includes a vacuum layer at the edge.", "date": "1991-02", "date_type": "published", "publication": "Physics of Fluids B", "volume": "3", "number": "2", "publisher": "American Institute of Physics", "pagerange": "406-413", "id_number": "CaltechAUTHORS:GREpofb91", "issn": "0899-8221", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GREpofb91", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AS03-76-SFO-0767" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76-CHO-3073" } ] }, "doi": "10.1063/1.859750", "primary_object": { "basename": "GREpofb91.pdf", "url": "https://authors.library.caltech.edu/records/3v531-d1k48/files/GREpofb91.pdf" }, "resource_type": "article", "pub_year": "1991", "author_list": "Greene, G. J. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/r7gap-18c44", "eprint_id": 31743, "eprint_status": "archive", "datestamp": "2023-08-19 21:20:38", "lastmod": "2023-10-17 20:20:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vu-Hoanh-Xuan", "name": { "family": "Vu", "given": "H. X." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Plasma collection by an obstacle", "ispublished": "pub", "full_text_status": "public", "keywords": "PLASMA DRIFT, MAGNETIZATION, SLABS, TOKAMAK DEVICES, THERMONUCLEAR REACTIONS, ELECTRON\u2212ION COLLISIONS, DRAG, LIMITERS, PLASMA SIMULATION, TWO\u2212DIMENSIONAL CALCULATIONS", "note": "\u00a9 1989 American Institute of Physics. \n\nReceived 22 June 1988; accepted 6 September 1988. \n\nThis work was supported by the U.S. Department of Energy, Office of Fusion Energy Grant No. DE-FG03-85ER53173 and the Magnetic Fusion Science Fellowship Program.\n\nPublished - VUHpofb89.pdf
", "abstract": "Plasma flow to an obstacle is examined using the two\u2010fluid equations. In this model the obstacle is assumed to be a two\u2010dimensional strip that extends to infinity in the y direction (slab geometry). An obstacle inserted into a magnetized plasma will cast a \"shadow\" along the magnetic field lines. The natural collection length of such an obstacle is a measure of the length of its shadow. This study shows that in a typical fusion tokamak, where c_s/\u03a9_(ci)d\u226a1 (\u03a9_(ci), c_s are the ion cyclotron frequency and the ion acoustic speed, respectively, d is the half\u2010width of the strip), the particle collection length of an obstacle can be approximated as L_\u2225=0.23c_sd^2/ D_\u22a5, if D_\u22a5/ c_sd \u226a1; or 0.30d, if D_\u22a5/ c_sd \u226b1. For the cases examined in this study, the inclusion of the electron\u2013ion collisional drag parallel to B_0 changes the solution only by an insignificant amount.", "date": "1989-01-01", "date_type": "published", "publication": "Physics of Fluids B", "volume": "1", "number": "1", "publisher": "American Institute of Physics", "pagerange": "68-71", "id_number": "CaltechAUTHORS:20120531-102516730", "issn": "0899-8221", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120531-102516730", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG03-85ER53173" }, { "agency": "Magnetic Fusion Science Fellowship Program" } ] }, "collection": "CaltechAUTHORS", "doi": "10.1063/1.859106", "primary_object": { "basename": "VUHpofb89.pdf", "url": "https://authors.library.caltech.edu/records/r7gap-18c44/files/VUHpofb89.pdf" }, "resource_type": "article", "pub_year": "1989", "author_list": "Vu, H. X. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/87t1x-sr645", "eprint_id": 10473, "eprint_status": "archive", "datestamp": "2023-08-22 04:38:51", "lastmod": "2023-10-16 22:53:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liewer-P-C", "name": { "family": "Liewer", "given": "P. C." } }, { "id": "McChesney-Jon-M", "name": { "family": "McChesney", "given": "J. M." } }, { "id": "Zweben-S-J", "name": { "family": "Zweben", "given": "S. J." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Temperature fluctuations and heat transport in the edge regions of a tokamak", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1986 American Institute of Physics. \n\nReceived 22 March 1985; accepted 8 September 1985. \n\nOne of the authors (P.C.L.) would like to thank Paul Bellan and Wendell Horton for helpful discussions. This work was supported by the Office of Fusion Energy of the U.S. Department of Energy.\n\nPublished - LIEpof86.pdf
", "abstract": "Electron temperature fluctuations have been investigated in the edge region of the Caltech research tokamak [S. J. Zweben and R. W. Gould, Nucl. Fusion 25, 171 (1985)], and an upper limit to this fluctuation level was found at Te/Te <~ 15%. This measurement, together with previous measurements of density and electric and magnetic field fluctuations, allows a unique comparison of the heat transport resulting from three basic turbulent mechanisms: (1) heat flux from the particle flux resulting from microscopic density and electric field fluctuations; (2) thermal conduction resulting from microscopic temperature and electric field fluctuations; and (3) thermal conduction resulting from microscopic magnetic field fluctuations. The measurements indicate that, in the edge regions, the electron heat transport caused by the measured turbulence-induced particle flux is comparable to or greater than that caused by the thermal conduction associated with the electron temperature and electric field fluctuations, and is significantly greater than that resulting from the measured magnetic fluctuations. This electron heat loss caused by the plasma turbulence is found to be an important electron energy loss mechanism in the edge regions.", "date": "1986-01", "date_type": "published", "publication": "Physics of Fluids", "volume": "29", "number": "1", "publisher": "American Institute of Physics", "pagerange": "309-317", "id_number": "CaltechAUTHORS:LIEpof86", "issn": "0031-9171", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:LIEpof86", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)" } ] }, "doi": "10.1063/1.865942", "primary_object": { "basename": "LIEpof86.pdf", "url": "https://authors.library.caltech.edu/records/87t1x-sr645/files/LIEpof86.pdf" }, "resource_type": "article", "pub_year": "1986", "author_list": "Liewer, P. C.; McChesney, J. M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dk15x-p5w74", "eprint_id": 32254, "eprint_status": "archive", "datestamp": "2023-08-22 03:48:57", "lastmod": "2023-10-17 23:04:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zweben-S-J", "name": { "family": "Zweben", "given": "S. J." } }, { "id": "Liewer-P-C", "name": { "family": "Liewer", "given": "P. C." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Local magnetic divertor for control of the plasma-limiter interaction in a tokamak", "ispublished": "pub", "full_text_status": "public", "keywords": "tokamak devices; plasma drift; magnet coils; magnetic fields; disturbances; plasma confinement; optimization; performance; limiters; divertors; control; toroidal configuration", "note": "\u00a9 1984 American Institute of Physics. \n\nReceived 14 January 1983; accepted 5 December 1983. \n\nWe thank J. A. Rome, R. Fowler, V. Lynch, and M. Peng for help in using the Oak Ridge National Laboratory magnetic field line codes. \n\nThis work was supported by the U.S. Department of Energy, under Contract No. DE-AS03-SF00767.\n\nPublished - ZWEpof84.pdf
", "abstract": "An experiment is described in which plasma flow to a tokamak limiter is controlled through the use of a local toroidal divertor coil mounted inside the limiter itself. This coil produces a local perturbed field B_C approximately equal to the local unperturbed toroidal field B_T \u2243 3 kG, such that when B_C adds to B_T the field lines move into the limiter and the local plasma flow to it increases by a factor as great as 1.6, and when B_C subtracts from B_T the field lines move away from the limiter and the local plasma flow to it decreases by as much as a factor of 4. A simple theoretical model is used to interpret these results. Since these changes occur without significantly affecting global plasma confinement, such a control scheme may be useful for optimizing the performance of pumped limiters.", "date": "1984-03", "date_type": "published", "publication": "Physics of Fluids", "volume": "27", "number": "3", "publisher": "American Institute of Physics", "pagerange": "691-703", "id_number": "CaltechAUTHORS:20120703-111751046", "issn": "0031-9171", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120703-111751046", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AS03-SF00767" } ] }, "doi": "10.1063/1.864678", "primary_object": { "basename": "ZWEpof84.pdf", "url": "https://authors.library.caltech.edu/records/dk15x-p5w74/files/ZWEpof84.pdf" }, "resource_type": "article", "pub_year": "1984", "author_list": "Zweben, S. J.; Liewer, P. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/r2gjy-j8q77", "eprint_id": 11446, "eprint_status": "archive", "datestamp": "2023-08-22 02:17:37", "lastmod": "2023-10-16 23:47:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hwang-David-Li-Shui-Quek", "name": { "family": "Hwang", "given": "D. Q." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Measurements of the complex plasma loading impedance of the magnetosonic cavity modes", "ispublished": "pub", "full_text_status": "public", "keywords": "PLASMA WAVES, MAGNETOACOUSTIC WAVES, ELECTRIC IMPEDANCE, TOKAMAK DEVICES, PLASMA DIAGNOSTICS, RESONANCE, Q\u2212VALUE, PLASMA HEATING, ICR HEATING, CAVITY RESONATORS, ANTENNAS, COLD PLASMA, COLLISIONLESS PLASMA, MAGNETIC FIELDS, DISPERSION RELATIONS, EIGENFREQUENCY, SIMULATION", "note": "\u00a9 1980 American Institute of Physics. \n\nReceived 23 May 1979; accepted 20 November 1979. \n\nOne of the authors (DQH) would like to express his appreciation to Dr. W. Bridges, Dr. J. Long, and Dr. H. Martel for the many useful discussions and suggestions. \n\nSpecial thanks go to F. Cosso for his skillful assistance in constructing the experimental instruments. \n\nThis work was supported by the U.S. Department of Energy Contract AT (04-3) 767, Project Agreement No. 2.\n\nPublished - HWApof80.pdf
", "abstract": "The complex plasma loading impedance of the fast magnetosonic wave in the Caltech tokamak has been investigated at low power (between 10 and 300 W). The magnetosonic cavity modes are observed both as voltage maxima at the output of a six-turn receiving probe, and as maxima in the input resistance of the transmitting antenna. When the real and imaginary parts of the measured plasma loading impedance are plotted in the complex impedance plane, the resulting curves are approximately circles, indicating a resonance phenomenon. The observed plasma loading resistance at the various cavity modes is as high as 3 to 4 times the basic antenna resistance (~0.4\u03a9). This means that efficient energy coupling into the tokamak and low losses in the antenna system are possible. The estimated cavity Q's are between 400 and 700.", "date": "1980-03", "date_type": "published", "publication": "Physics of Fluids", "volume": "23", "number": "3", "publisher": "American Institute of Physics", "pagerange": "614-623", "id_number": "CaltechAUTHORS:HWApof80", "issn": "0031-9171", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:HWApof80", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Departement of Energy (DOE)", "grant_number": "AT (04-3) 767" } ] }, "doi": "10.1063/1.863032", "primary_object": { "basename": "HWApof80.pdf", "url": "https://authors.library.caltech.edu/records/r2gjy-j8q77/files/HWApof80.pdf" }, "resource_type": "article", "pub_year": "1980", "author_list": "Hwang, D. Q. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/thfqp-6rs84", "eprint_id": 3744, "eprint_status": "archive", "datestamp": "2023-08-22 01:46:27", "lastmod": "2023-10-16 16:08:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Levine-Bruce-S", "name": { "family": "Levine", "given": "B." } }, { "id": "Greene-Glenn-J", "name": { "family": "Greene", "given": "G. J." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Focusing resonance cones", "ispublished": "pub", "full_text_status": "public", "keywords": "COLLISIONLESS PLASMA; PLASMA FOCUS; MAGNETIC FIELDS; ELECTRIC POTENTIAL; RINGS; COLD PLASMA; TEMPERATURE EFFECTS; SINGULARITY", "note": "\u00a9 1978 American Institute of Physics. \n\nReceived 7 November 1977. \n\nThis research was supported by the U. S. Department of Energy under Contract E(04-3)-767.\n\nPublished - LEVpof78.pdf
", "abstract": "The potential for an oscillating ring source immersed in cold, magnetized, collisionless plasma in the resonance cone regime (K_\u2225/K_\u22a5< 0 ) is evaluated exactly and asymptotically, giving insight into the gross spatial behavior of the focusing resonance cones. The nature of the singularity in potential is clarified by the introduction of a noninfinitesimal collision frequency. Thermal effects are considered numerically, revealing an interesting interference structure in potential as well as a density depression near the focus of the cone due to the ponderomotive force.", "date": "1978-07", "date_type": "published", "publication": "Physics of Fluids", "volume": "21", "number": "7", "publisher": "American Institute of Physics", "pagerange": "1116-1119", "id_number": "CaltechAUTHORS:LEVpof78", "issn": "1070-6631", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:LEVpof78", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "E(04-3)-767" } ] }, "doi": "10.1063/1.862351", "primary_object": { "basename": "LEVpof78.pdf", "url": "https://authors.library.caltech.edu/records/thfqp-6rs84/files/LEVpof78.pdf" }, "resource_type": "article", "pub_year": "1978", "author_list": "Levine, B.; Greene, G. J.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/w74rm-j9s56", "eprint_id": 3721, "eprint_status": "archive", "datestamp": "2023-08-22 01:17:57", "lastmod": "2023-10-16 16:07:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Dawson-J-M", "name": { "family": "Dawson", "given": "J. M." } }, { "id": "Kim-H-C", "name": { "family": "Kim", "given": "H. C." } }, { "id": "Arnush-D", "name": { "family": "Arnush", "given": "D." } }, { "id": "Fried-B-D", "name": { "family": "Fried", "given": "B. D." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "Heflinger-L-O", "name": { "family": "Heflinger", "given": "L. O." } }, { "id": "Kennel-C-F", "name": { "family": "Kennel", "given": "C. F." } }, { "id": "Romesser-T-E", "name": { "family": "Romesser", "given": "T. E." } }, { "id": "Stenzel-Reiner-L", "name": { "family": "Stenzel", "given": "R. L." } }, { "id": "Wong-A-Y", "name": { "family": "Wong", "given": "A. Y." } }, { "id": "Wuerker-R-F", "name": { "family": "Wuerker", "given": "R. F." } } ] }, "title": "Isotope separation in plasmas by use of ion cyclotron resonance", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91976 The American Physical Society. \n\nReceived 23 September 1976. \n\nThis work was supported by TRW Independent Research and Development and by U.S. Department of Energy and Research Development Administration under Contract No. E(49-15)-3086L.\n\nPublished - DAWprl76.pdf
", "abstract": "Selective ion-cyclotron-resonance acceleration of individual K, Ne, Cl, A, and Xe isotopes has been observed in plasmas of density 10\u2079 to 10\u00b9\u00b9 cm\u207b\u00b3. Energy discriminating probes show good resolution of accelerated species in all cases. Mass spectrometer analyses of potassium samples, collected on cooled tungsten ribbons, showed \u2074\u00b9K to \u00b3\u2079K abundance ratios of 4 rather than the normal value of 0.07.", "date": "1976-12-06", "date_type": "published", "publication": "Physical Review Letters", "volume": "37", "number": "23", "publisher": "American Physical Society", "pagerange": "1547-1550", "id_number": "CaltechAUTHORS:DAWprl76", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DAWprl76", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Energy Research and Development Administration (ERDA)", "grant_number": "E(49-15)-3086L" } ] }, "doi": "10.1103/PhysRevLett.37.1547", "primary_object": { "basename": "DAWprl76.pdf", "url": "https://authors.library.caltech.edu/records/w74rm-j9s56/files/DAWprl76.pdf" }, "resource_type": "article", "pub_year": "1976", "author_list": "Dawson, J. M.; Kim, H. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bhsqx-9fk35", "eprint_id": 33189, "eprint_status": "archive", "datestamp": "2023-08-19 09:35:16", "lastmod": "2023-10-18 18:52:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "Healey-J-T", "name": { "family": "Healey", "given": "J. T." } } ] }, "title": "Secondary fluorescent excitation in the scanning electron microscope: Improved sensitivity of energy dispersive analysis", "ispublished": "pub", "full_text_status": "public", "keywords": "X\u2212RAY SPECTROSCOPY, ENERGY SPECTRA, FLUORESCENCE, SENSITIVITY, RESOLUTION, STAINLESS STEELS, ELECTRON MICROSCOPES", "note": "\u00a9 1975 American Institute of Physics. \n\nReceived 27 June 1975. Online Publication Date: 2 September 2008.\n\nPublished - GOUrsi75.pdf
", "abstract": "The use of secondary fluorescence for x\u2010ray energy spectroscopy in the scanning electron microscope has greatly enhanced both resolution and the lower limit of detection. This note describes a simple secondary fluorescence system. The x\u2010ray energy spectra taken from a stainless steel sample illustrate the advantages of this method.", "date": "1975-10", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "46", "number": "10", "publisher": "American Institute of Physics", "pagerange": "1427-1428", "id_number": "CaltechAUTHORS:20120814-152848159", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120814-152848159", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.1134022", "primary_object": { "basename": "GOUrsi75.pdf", "url": "https://authors.library.caltech.edu/records/bhsqx-9fk35/files/GOUrsi75.pdf" }, "resource_type": "article", "pub_year": "1975", "author_list": "Gould, R. W. and Healey, J. T." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/j8ze0-svz83", "eprint_id": 33146, "eprint_status": "archive", "datestamp": "2023-08-19 08:15:56", "lastmod": "2023-10-18 18:50:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Singh-Nagendra", "name": { "family": "Singh", "given": "N." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Waves in a hot uniaxial plasma excited by a current source", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1973 American Institute of Physics. \n\nReceived 26 April 1971; final manuscript received 28 August 1972. \n\nThis research was supported in part by the Office of Naval Research under Contract No. 220(50) and in part by the Atomic Energy Commission under Contract AT(04-3)-767. The original manuscript was prepared under Atomic Energy Commission Contract AT(11-1)-2059.\n\nPublished - SINpof73.pdf
", "abstract": "The fields excited by a short dipole antenna in a hot uniaxially anisotropic plasma (B\u2080 \u2192 \u221e) have been studied. When \u03c9 < \u03c9\u209a, the dipole effectively excites two propagating waves, a slow wave and a fast wave, inside a cone of half\u2010cone angle sin\u207b\u00b9(\u03c9/\u03c9\u209a). Inside the cone a characteristic interference structure in the angular distribution of the fields is noted. Outside the cone fields fall off exponentially. The appearance of the cone and the characteristic interference structure in the field is useful from the viewpoint of laboratory diagnostics.", "date": "1973-01", "date_type": "published", "publication": "Physics of Fluids", "volume": "16", "number": "1", "publisher": "American Institute of Physics", "pagerange": "75-81", "id_number": "CaltechAUTHORS:20120813-164607358", "issn": "1070-6631", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120813-164607358", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" }, { "agency": "Atomic Energy Commission", "grant_number": "AT(04-3)-767" }, { "agency": "Atomic Energy Commission", "grant_number": "AT(11-1)-2059" } ] }, "doi": "10.1063/1.1694176", "primary_object": { "basename": "SINpof73.pdf", "url": "https://authors.library.caltech.edu/records/j8ze0-svz83/files/SINpof73.pdf" }, "resource_type": "article", "pub_year": "1973", "author_list": "Singh, N. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/t86sg-6mx60", "eprint_id": 121834, "eprint_status": "archive", "datestamp": "2023-08-22 00:10:35", "lastmod": "2023-10-20 16:18:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Singh-Nagendra", "name": { "family": "Singh", "given": "N." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Radiation From a Short Electric Dipole in a Hot Uniaxial Plasma", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrical and Electronic Engineering; General Earth and Planetary Sciences; Condensed Matter Physics", "note": "\u00a9 1971 American Geophysical Union. \n\nThis research was supported in part by the Office of Naval Research under Contract Nonr 220(50) and in part by the Atomic Energy Commission under Contract AT(04-3)-767. The manuscript was prepared through Atomic Energy Commission Contract AT (11-1)-2059.\n\nPublished - 1-s2.0-S1053811922007005-main.pdf
", "abstract": "The effects of electron temperature on the radiation fields and the resistance of a short electric dipole antenna embedded in a uniaxial plasma have been studied. The radiation condition for solving Maxwell's equations is discussed, and the phase and group velocities for propagation are given. It is found that for \u03c9 < \u03c9_\u03c1 the antenna excites two waves, a slow wave and a fast wave. These waves propagate only within a cone whose axis is parallel to the biasing magnetostatic field B\u2080 and whose half-cone angle is slightly less than sin\u207b\u00b9 (\u03c9/\u03c9_\u03c1). In the case of \u03c9 > \u03c9_\u03c1 the antenna excites two separate modes of radiation. One of the modes is the electromagnetic mode, while the other mode is of hot plasma origin. A characteristic interference structure is noted in the angular distribution of the field. The input and the radiation resistances are calculated and are shown to remain finite for nonzero electron thermal velocities. The effect of Landau damping and the antenna length on the input and the radiation resistances has been considered.", "date": "1971-12", "date_type": "published", "publication": "Radio Science", "volume": "6", "number": "12", "publisher": "American Geophysical Union", "pagerange": "1151-1162", "id_number": "CaltechAUTHORS:20230612-708583000.3", "issn": "0048-6604", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230612-708583000.3", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "Nonr 220(50)" }, { "agency": "Atomic Energy Commission", "grant_number": "AT(04-3)-767" }, { "agency": "Atomic Energy Commission", "grant_number": "AT(11-1)-2059" } ] }, "doi": "10.1029/rs006i012p01151", "primary_object": { "basename": "1-s2.0-S1053811922007005-main.pdf", "url": "https://authors.library.caltech.edu/records/t86sg-6mx60/files/1-s2.0-S1053811922007005-main.pdf" }, "resource_type": "article", "pub_year": "1971", "author_list": "Singh, N. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bxy85-6x542", "eprint_id": 11600, "eprint_status": "archive", "datestamp": "2023-08-22 00:09:12", "lastmod": "2023-10-17 15:09:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stenzel-Reiner-L", "name": { "family": "Stenzel", "given": "R. L." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Upper-Hybrid Resonance Absorption, Emission, and Heating of an Afterglow Plasma Column", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1971 The American Institute of Physics. \n\nReceived 22 March 1971. \n\nThe authors gratefully acknowledge support from the U.S. Atomic Energy Commission for this work, and various interesting discussions with R.H. Ault concerning the theoretical investigation of the absorption coefficient, and for the use of his numerical results prior to publication.\n\nPublished - STEjap71.pdf
", "abstract": "Microwave absorption and emission and electron temperatures of a nonuniform axially magnetized afterglow plasma column in a waveguide geometry have been investigated experimentally. Frequency omega and magnetic field omegac are chosen to satisfy the upper-hybrid resonance condition omega2=omegac2+omegap2(r), where omegap(r) is the local electron plasma frequency. Nearly perfect absorption is observed in the range of upper-hybrid frequencies, while at other frequencies the absorption coefficient is essentially zero. The sharp absorption onset at the maximum upper-hybrid frequency yields an accurate measure for the peak electron density. Density decay and profile in the plasma column are observed\u2014the latter using a new technique. In the range of high absorption the noise emission approaches the blackbody limit. The electron temperature is measured with a radiometer and a reference noise source in a new technique yielding both spatial and time dependence without perturbing the plasma. The time resolution is obtained by a sampling technique. The spatial resolution results from the fact that upper-hybrid resonance absorption and emission are confined to a narrow resonant layer. This property is also used to heat the electrons locally and observe the thermalization process.", "date": "1971-10", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "42", "number": "11", "publisher": "American Institute of Physics", "pagerange": "4225-4235", "id_number": "CaltechAUTHORS:STEjap71", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:STEjap71", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Atomic Energy Commission" } ] }, "doi": "10.1063/1.1659758", "primary_object": { "basename": "STEjap71.pdf", "url": "https://authors.library.caltech.edu/records/bxy85-6x542/files/STEjap71.pdf" }, "resource_type": "article", "pub_year": "1971", "author_list": "Stenzel, R. L. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5mj4z-khk76", "eprint_id": 11445, "eprint_status": "archive", "datestamp": "2023-08-22 00:05:38", "lastmod": "2023-10-16 23:47:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fisher-Raymond-K", "name": { "family": "Fisher", "given": "R. K." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Resonance Cones in the Field Pattern of a Radio Frequency Probe in a Warm Anisotropic Plasma", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1971 American Institute of Physics. \n\nReceived 29 June 1970. \n\nThe authors gratefully acknowledge N. Singh for his work on theoretical aspects of this research. \n\nThis research was supported in part by the Office of Naval Research under Contract Nonr 220(05) and in part by the Atomic Energy Commission under Contract AT(04-3)-767. In addition, one of the authors (R.K.F.) received support as a National Science Foundation Graduate Fellow.\n\nPublished - FISpof71.pdf
", "abstract": "An experimental and theoretical investigation of the angular distribution of the electric field of a short radio frequency probe in a plasma in a magnetic field is described. The field is observed to become very large along a resonance cone whose axis is parallel to the static magnetic field and whose opening angle is observed to vary with incident probe frequency, cyclotron frequency, and plasma frequency in agreement with simple cold plasma dielectric theory. The relationship of these cones to the limiting phase- and group-velocity cones which appear in the theory of plane wave propagation is discussed. The addition of electron thermal velocities (warm plasma effects) is examined in the limit of a large static magnetic field. A fine structure appears inside the cones and is shown to result from an interference between a fast electromagnetic wave and a slow plasma wave. This interference structure is observed experimentally and measurements of the angular interference spacing are shown to agree with the warm plasma theory. The use of measurements of the resonance cones and structure as a diagnostic tool to determine the plasma density and electron temperature in a plasma in a magnetic field is discussed.", "date": "1971-04", "date_type": "published", "publication": "Physics of Fluids", "volume": "14", "number": "4", "publisher": "American Institute of Physics", "pagerange": "857-867", "id_number": "CaltechAUTHORS:FISpof71", "issn": "0031-9171", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:FISpof71", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "Nonr 220(05)" }, { "agency": "Atomic Energy Commission", "grant_number": "AT(04-3)-767" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "doi": "10.1063/1.1693521", "primary_object": { "basename": "FISpof71.pdf", "url": "https://authors.library.caltech.edu/records/5mj4z-khk76/files/FISpof71.pdf" }, "resource_type": "article", "pub_year": "1971", "author_list": "Fisher, R. K. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/46h6q-zsd07", "eprint_id": 12375, "eprint_status": "archive", "datestamp": "2023-08-22 00:03:27", "lastmod": "2023-10-17 16:43:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stenzel-Reiner-L", "name": { "family": "Stenzel", "given": "R. L." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Longitudinal Oscillations in Bounded Magnetoplasmas", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1971 American Institute of Physics. \n\nReceived 26 June 1970. \n\nThis work was supported by the United States Atomic Energy Commission under Contract AT (04-3)-767.\n\nPublished - STEpof71.pdf
", "abstract": "Fine structure in absorption due to Buchsbaum-Hasegawa modes is observed over a wider range of magnetic fields than previously reported (omegac/omega = 0.5\u22120.985). The basic theory is satisfactory only near the cyclotron harmonic.", "date": "1971-01", "date_type": "published", "publication": "Physics of Fluids", "volume": "14", "number": "1", "publisher": "American Institute of Physics", "pagerange": "187-188", "id_number": "CaltechAUTHORS:STEpof71", "issn": "0031-9171", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:STEpof71", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Atomic Energy Commission", "grant_number": "AT (04-3) 767" } ] }, "doi": "10.1063/1.1693274", "primary_object": { "basename": "STEpof71.pdf", "url": "https://authors.library.caltech.edu/records/46h6q-zsd07/files/STEpof71.pdf" }, "resource_type": "article", "pub_year": "1971", "author_list": "Stenzel, R. L. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/vpg1c-g4r78", "eprint_id": 8820, "eprint_status": "archive", "datestamp": "2023-08-21 23:57:36", "lastmod": "2023-10-16 21:45:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nishikawa-Kyoji", "name": { "family": "Nishikawa", "given": "Kyoji" } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Numerical Study of Collisional Effects on Spatial Ion-Wave Echoes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1970 American Institute of Physics. \n\n(Received 12 December 1969) \n\nThe authors are grateful to Dr. H. Ikezi for helpful discussions. \n\nThis paper presents the results of one phase of research carried out at the Jet Propulsion Laboratory, California Institute of Technology, under Contract No. NAS 7-100, sponsored by the National Aeronautics and Space Administration. It is also supported by the United States Atomic Energy Commission under Contract No. AT (04-3)-767. \n\n[K.N. was] a National Research Council Resident Research Associate, on leave of absence from the Department of Physics, Faculty of Science, Kyoto University, Kyoto, Japan.\n\nPublished - NISpof70.pdf
", "abstract": "Collisional effects on the second-order spatial ion-wave echo are studied numerically. General agreement is obtained with the experimental results of Ikezi, Takahashi, and Nishikawa. A critical argument is raised against the validity of the small collision approximation.", "date": "1970-07", "date_type": "published", "publication": "Physics of Fluids", "volume": "13", "number": "7", "publisher": "American Institute of Physics", "pagerange": "1883-1885", "id_number": "CaltechAUTHORS:NISpof70", "issn": "0031-9171", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:NISpof70", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech", "grant_number": "NAS 7-100" }, { "agency": "Atomic Energy Commission", "grant_number": "AT (04-3)-767" }, { "agency": "National Research Council" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.1063/1.1693174", "primary_object": { "basename": "NISpof70.pdf", "url": "https://authors.library.caltech.edu/records/vpg1c-g4r78/files/NISpof70.pdf" }, "resource_type": "article", "pub_year": "1970", "author_list": "Nishikawa, Kyoji and Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/whg45-f8y31", "eprint_id": 121833, "eprint_status": "archive", "datestamp": "2023-08-21 23:55:43", "lastmod": "2023-10-20 16:18:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fisher-Raymond-K", "name": { "family": "Fisher", "given": "R.K." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R.W." } } ] }, "title": "Resonance cone structure in warm anisotropic plasma", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy", "note": "\u00a9 1970 Elsevier. \n\nResearch supported in part by the U.S. Office of Naval Research and in part by the U.S. Atomic Energy Commission.", "abstract": "A fine structure is observed near the resonance cones in the field pattern of a small r.f. probe and is shown to result from an interference between a fast electromagnetic wave (v_( group) \u223c c) and a slow plasma wave (v_(group) \u223c v_(th)).", "date": "1970-03-09", "date_type": "published", "publication": "Physics Letters A", "volume": "31", "number": "5", "publisher": "Elsevier", "pagerange": "235-236", "id_number": "CaltechAUTHORS:20230612-707158000.1", "issn": "0375-9601", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230612-707158000.1", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" }, { "agency": "Atomic Energy Commission" } ] }, "doi": "10.1016/0375-9601(70)90946-1", "resource_type": "article", "pub_year": "1970", "author_list": "Fisher, R.K. and Gould, R.W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/e406b-2k151", "eprint_id": 38496, "eprint_status": "archive", "datestamp": "2023-08-19 06:51:31", "lastmod": "2023-10-23 20:13:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stenzel-Reiner-L", "name": { "family": "Stenzel", "given": "R. L." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Afterglow Plasma Diagnostics with a Microwave Sampling Radiometer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1969 The American Institute of Physics. \n\nReceived 6 June 1969. \n\nThe authors are indebted to Professor R.S. Harp for interesting discussions and suggestions during the course of this research. In addition, we benefitted from Professor A. Moffet's experience in designing a low noise i.f. preamplifier. \n\nThis work was supported by the U. S. Atomic Energy Commission.\n\nPublished - STErsi69.pdf
", "abstract": "A simple waveguide arrangement has been developed for the study of microwave absorption and emission from a magnetized afterglow plasma column. The time and frequency resolved measurements are performed by a sampling radiometer. A comparison and null technique permits the direct measurement of the electron temperature. Continuous plots of the temperature vs frequency, magnetic field, and afterglow time are made possible by means of a servoloop. The width of the emission or absorption spectrum in the range of upper hybrid frequencies is used to derive the electron density which, together with the temperature measurement, allows a more complete analysis of the plasma decay.", "date": "1969-11", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "40", "number": "11", "publisher": "American Institute of Physics", "pagerange": "1461-1466", "id_number": "CaltechAUTHORS:20130514-105315485", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130514-105315485", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Atomic Energy Commission" } ] }, "doi": "10.1063/1.1683827", "primary_object": { "basename": "STErsi69.pdf", "url": "https://authors.library.caltech.edu/records/e406b-2k151/files/STErsi69.pdf" }, "resource_type": "article", "pub_year": "1969", "author_list": "Stenzel, R. L. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5rayr-6zx03", "eprint_id": 121845, "eprint_status": "archive", "datestamp": "2023-08-21 23:49:45", "lastmod": "2023-10-20 16:18:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R.W." } } ] }, "title": "Pulse amplification in nonlinear systems", "ispublished": "pub", "full_text_status": "public", "keywords": "General Physics and Astronomy", "note": "\u00a9 1969 Published by Elsevier. \n\nThis research was supported by the Office of Naval Research.", "abstract": "It is shown that a system of weakly anharmonic oscillators can be used to amplify pulses. The conditions for amplification are given.", "date": "1969-06-02", "date_type": "published", "publication": "Physics Letters A", "volume": "29A", "number": "6", "publisher": "Elsevier", "pagerange": "347-348", "id_number": "CaltechAUTHORS:20230612-708640000.22", "issn": "0375-9601", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230612-708640000.22", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" } ] }, "doi": "10.1016/0375-9601(69)90165-0", "resource_type": "article", "pub_year": "1969", "author_list": "Gould, R.W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xre73-sz697", "eprint_id": 94209, "eprint_status": "archive", "datestamp": "2023-08-19 06:27:03", "lastmod": "2023-10-20 17:46:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Cyclotron Echo Phenomena", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1969 American Association of Physics Teachers. \n\nReceived 11 February 1969. \n\nThe author gratefully acknowledges support from the Office of Naval Research for work in this area and numerous critical discussions with his colleagues about the subject, including W. H. Kegel, F. A. Blum, L. O. Bauer, R. S. Harp, D. E. Kaplan, R. M. Hill, and B. D. Fried.\n\nPublished - 1.1975717.pdf
", "abstract": "The physical mechanisms by which echoes are produced in a system of many charged particles gyrating in a static magnetic field is outlined. It is then shown how these ideas carry over to large systems of (almost) harmonic oscillators and are therefore applicable to many other physical systems.", "date": "1969-06", "date_type": "published", "publication": "American Journal of Physics", "volume": "37", "number": "6", "publisher": "American Association of Physics Teachers", "pagerange": "585-597", "id_number": "CaltechAUTHORS:20190327-102620123", "issn": "0002-9505", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190327-102620123", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" } ] }, "doi": "10.1119/1.1975717", "primary_object": { "basename": "1.1975717.pdf", "url": "https://authors.library.caltech.edu/records/xre73-sz697/files/1.1975717.pdf" }, "resource_type": "article", "pub_year": "1969", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4c6m2-gyd08", "eprint_id": 3558, "eprint_status": "archive", "datestamp": "2023-08-21 23:49:27", "lastmod": "2023-10-16 15:59:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fisher-R-K", "name": { "family": "Fisher", "given": "R. K." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Resonance cones in the field pattern of a short antenna in an anisotropic plasma", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91969 The American Physical Society. \n\nReceived 10 March 1969 \n\nResearch supported in part by the U.S. Atomic Energy Commission and in part by the Office of Naval Research. [R.K.F. was a] National Science Foundation Predoctoral Fellow.\n\nPublished - FISprl69.pdf
", "abstract": "We report experimental observation of resonance cones in the angular distribution of the radio-frequency electric field of a short antenna in a plasma in a static magnetic field. The cone angle is observed to vary with incident frequency, cyclotron frequency, and plasma frequency in agreement with simple plasma dielectric theory. We discuss the relationship of these cones to the limiting phase- and group-velocity cones which appear in the theory of plane wave propagation.", "date": "1969-05-26", "date_type": "published", "publication": "Physical Review Letters", "volume": "22", "number": "21", "publisher": "American Physical Society", "pagerange": "1093-1095", "id_number": "CaltechAUTHORS:FISprl69", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:FISprl69", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Atomic Energy Commission" }, { "agency": "Office of Naval Research (ONR)" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "doi": "10.1103/PhysRevLett.22.1093", "primary_object": { "basename": "FISprl69.pdf", "url": "https://authors.library.caltech.edu/records/4c6m2-gyd08/files/FISprl69.pdf" }, "resource_type": "article", "pub_year": "1969", "author_list": "Fisher, R. K. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/krcjm-74q15", "eprint_id": 33575, "eprint_status": "archive", "datestamp": "2023-08-19 06:24:58", "lastmod": "2023-10-18 20:26:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Blum-F-A", "name": { "family": "Blum", "given": "F. A." } }, { "id": "Bauer-Luc-O-E", "name": { "family": "Bauer", "given": "L. O." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "Stenzel-Reiner-L", "name": { "family": "Stenzel", "given": "R. L." } } ] }, "title": "Microwave Scattering and Noise Emission from Afterglow\n Plasmas in a Magnetic Field", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1969 The American Institute of Physics. \n\nReceived 15 November 1968. \n\nWe are indebted to R. S. Harp for comments and suggestions during the course of this research. This work was supported by the United States Office of Naval Research under Contract Nonr 220(50). One of the authors (F.A.B) received support as a Howard Hughes Predoctoral Fellow and another of the authors (L.O.B.) received partial support from the Swiss Council of Scientific Research.\n\nPublished - BLUpof69.pdf
", "abstract": "The microwave reflection and noise emission (extraordinary mode) from cylindrical rare\u2010gas (He, Ne, Ar) afterglow plasmas in an axial magnetic field is described. Reflection and noise emission are measured as a function of magnetic field near electron cyclotron resonance (\u03c9\u2009\u2248\u2009\u03c9\ua700) with electron density as a parameter (\u03c9\u209a\u2009<\u2009\u03c9). A broad peak, which shifts to lower values of \u03c9\ua700/\u03c9) as electron density increases, is observed for (\u03c9\ua700/\u03c9)\u2009\u2264\u20091. For all values of electron density a second sharp peak is found very close to cyclotron resonance in reflection measurements. This peak does not occur in the emission data. Calculations of reflection and emission using a theoretical model consisting of a one\u2010dimensional, cold plasma slab with nonuniform electron density yield results in qualitative agreement with the observations. Both the experimental and theoretical results suggest that the broad, density\u2010dependent peak involves resonance effects at the upper hybrid frequency ((\u03c9\u2095\u00b2\u2009=\u2009(\u03c9\ua700\u00b2\u2009+\u2009(\u03c9\u209a\u00b2) of the plasma.", "date": "1969-05", "date_type": "published", "publication": "Physics of Fluids", "volume": "12", "number": "5", "publisher": "American Institute of Physics", "pagerange": "1018-1027", "id_number": "CaltechAUTHORS:20120827-144355658", "issn": "1070-6631", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120827-144355658", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "Nonr-220(50)" }, { "agency": "Hughes Research Laboratories" }, { "agency": "Swiss Council of Scientific Research" } ] }, "doi": "10.1063/1.2163662", "primary_object": { "basename": "BLUpof69.pdf", "url": "https://authors.library.caltech.edu/records/krcjm-74q15/files/BLUpof69.pdf" }, "resource_type": "article", "pub_year": "1969", "author_list": "Blum, F. A.; Bauer, L. O.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/v8qhc-0pd78", "eprint_id": 33633, "eprint_status": "archive", "datestamp": "2023-08-19 06:24:24", "lastmod": "2023-10-18 20:29:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mason-Peter-V", "name": { "family": "Mason", "given": "P. V." }, "orcid": "0000-0002-7963-7420" }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Slow\u2010Wave Structures Utilizing Superconducting Thin\u2010Film Transmission Lines", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1969 The American Institute of Physics.\n\nMuch of this work was performed at the California Institute\nof Technology, and was supported by the Office of Naval Research, Washington, D.C. The remainder, which was performed at the Jet Propulsion Laboratory, was supported by the National Aeronautics and Space Administration.\n\nPublished - MASjap69.pdf
", "abstract": "Slow\u2010wave propagation of electromagnetic waves in transmission lines formed of thin\u2010film superconductors has been studied theoretically and experimentally. Previous theoretical analyses have been extended to include nonlocal theories. Strong dependence of phase velocity is found on film thickness and interfilm spacing when these become less than a few penetration depths. Velocity is also modified by coherence length, mean free path, nature of reflection of electrons at the film surfaces, and by temperature and magnetic field. Experimental measurements were made to verify the dependence on thickness, spacing, and temperature by means of a resonance technique. Agreement with theory was excellent in the case of temperature. Data taken for varying thickness and spacing verified the general trend of theoretical predictions. They indicate a nonlocal behavior with some specular reflection, but scatter of the data taken for different films prevents precise comparison of theory and experiment. Estimates of bulk penetration depths were made for indium, \u03bb_In = 648\u00b1130 \u00c5. For tantalum a rough estimate could be made of \u03bbTa = 580 \u00c5. Data were consistent with the estimate of coherence length for indium of \u03be_0 \u2248 3000 \u00c5. Velocity was found to be independent of frequency in the range 50\u2013500 MHz, while losses increased as the square. Pulse measurements indicated that delays of several microseconds and storage of several thousand pulses on a single line are feasible.", "date": "1969-04-01", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "40", "number": "5", "publisher": "American Institute of Physics", "pagerange": "2039-2051", "id_number": "CaltechAUTHORS:20120828-161331360", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120828-161331360", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" }, { "agency": "NASA/JPL" } ] }, "doi": "10.1063/1.1657907", "primary_object": { "basename": "MASjap69.pdf", "url": "https://authors.library.caltech.edu/records/v8qhc-0pd78/files/MASjap69.pdf" }, "resource_type": "article", "pub_year": "1969", "author_list": "Mason, P. V. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/faft8-99t70", "eprint_id": 6114, "eprint_status": "archive", "datestamp": "2023-08-21 23:42:44", "lastmod": "2023-10-16 20:08:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Malmberg-J-H", "name": { "family": "Malmberg", "given": "J. H." } }, { "id": "Wharton-C-B", "name": { "family": "Wharton", "given": "C. B." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "O'Neil-T-M", "name": { "family": "O'Neil", "given": "T. M." } } ] }, "title": "Observation of plasma wave echoes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1968 American Institute of Physics. \n\nReceived 22 September 1967. \n\nWe thank C.D. Moore and P.J. Vidmar for assistance with the instrumentation and measurements. This research was sponsored by the Defense Atomic Support Agency under contract DA-49-146-XZ-486.\n\nPublished - MALpof68.pdf
", "abstract": "Experimental observation of a new nonlinear plasma phenomenon, the plasma wave echo, is reported. A recent theory predicts that if a longitudinal electron plasma wave is excited at one position in a collisionless plasma and Landau damps away, and a second wave is excited at another position and also damps away, then a third wave (i.e., the echo) will spontaneously appear at a third position. The existence of various echoes, associated with various orders of the perturbation theory, is demonstrated experimentally. The echoes appear at the predicted position in the plasma. The frequency of the echo wave and the dependence of its amplitude on the amplitude of the initial wave are also in agreement with the theory. Experimental data on the saturation of echo amplitude with increasing initial wave amplitude and increasing distance are given. Data are also presented on another new, but related, phenomenon \"the sheath echo.\"", "date": "1968-06", "date_type": "published", "publication": "Physics of Fluids", "volume": "11", "number": "6", "publisher": "Physics of Fluids", "pagerange": "1147-1153", "id_number": "CaltechAUTHORS:MALpof68", "issn": "0031-9171", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:MALpof68", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Atomic Support Agency (DASA)", "grant_number": "DA-49-146-XZ-486" } ] }, "doi": "10.1063/1.1692075", "primary_object": { "basename": "MALpof68.pdf", "url": "https://authors.library.caltech.edu/records/faft8-99t70/files/MALpof68.pdf" }, "resource_type": "article", "pub_year": "1968", "author_list": "Malmberg, J. H.; Wharton, C. B.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/t25ww-4wz16", "eprint_id": 5342, "eprint_status": "archive", "datestamp": "2023-08-21 23:41:08", "lastmod": "2023-10-16 19:10:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bauer-Luc-O-E", "name": { "family": "Bauer", "given": "L. O." } }, { "id": "Blum-F-A", "name": { "family": "Blum", "given": "F. A." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Plasma echoes at upper hybrid resonance", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1968 The American Physical Society. \n\nReceived 14 December 1967. \n\nResearch supported by the U.S. Office of Naval Research under Contract No. Nonr 220(50). The authors are indebted to R.S. Harp, R.M. Hill, D.E. Kaplan, and A.Y. Wong for interesting discussions and communication of their work during the course of this research. In addition, we benefited from stimulating conversations with F.L. Hinton. [F.A.B. was a] National Science Foundation Predoctoral Fellow.\n\nPublished - BAUprl68.pdf
", "abstract": "We report experimental observation of a new plasma echo at upper hybrid resonance and present a simple theoretical model which exhibits some major features of the results.", "date": "1968-02-26", "date_type": "published", "publication": "Physical Review Letters", "volume": "20", "number": "9", "publisher": "American Physical Society", "pagerange": "435-439", "id_number": "CaltechAUTHORS:BAUprl68", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:BAUprl68", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "Nonr 220(50)" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "doi": "10.1103/physrevlett.20.435", "primary_object": { "basename": "BAUprl68.pdf", "url": "https://authors.library.caltech.edu/records/t25ww-4wz16/files/BAUprl68.pdf" }, "resource_type": "article", "pub_year": "1968", "author_list": "Bauer, L. O.; Blum, F. A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/257zz-0gg19", "eprint_id": 3708, "eprint_status": "archive", "datestamp": "2023-08-21 23:40:27", "lastmod": "2023-10-16 16:07:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Malmberg-J-H", "name": { "family": "Malmberg", "given": "J. H." } }, { "id": "Wharton-C-B", "name": { "family": "Wharton", "given": "C. B." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "O'Neil-T-M", "name": { "family": "O'Neil", "given": "T. M." } } ] }, "title": "Plasma wave echo experiment", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1968 The American Physical Society. \n\nReceived 22 September 1967. \n\nThis research was sponsored by the Defense Atomic Support Agency under Contract No. DA-49-146-XZ-486.\n\nPublished - MALprl68.pdf
", "abstract": "Experimental observation of a new nonlinear plasma phenomenon, the plasma wave echo, is reported.", "date": "1968-01-15", "date_type": "published", "publication": "Physical Review Letters", "volume": "20", "number": "3", "publisher": "American Physical Society", "pagerange": "95-97", "id_number": "CaltechAUTHORS:MALprl68", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:MALprl68", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Atomic Support Agency (DASA)", "grant_number": "DA-49-146-XZ-486" } ] }, "doi": "10.1103/PhysRevLett.20.95", "primary_object": { "basename": "MALprl68.pdf", "url": "https://authors.library.caltech.edu/records/257zz-0gg19/files/MALprl68.pdf" }, "resource_type": "article", "pub_year": "1968", "author_list": "Malmberg, J. H.; Wharton, C. B.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qddf6-xjm06", "eprint_id": 3740, "eprint_status": "archive", "datestamp": "2023-08-21 23:40:12", "lastmod": "2023-10-16 16:08:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "O'Neil-T-M", "name": { "family": "O'Neil", "given": "T. M." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Temporal and spatial plasma wave echoes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1968 American Institute of Physics. \n\nReceived 21 August 1967. \n\nThe authors wish to thank Dr. J. H. Malmberg for many valuable discussions in the course of this investigation. This research was supported in part by the Air Force Office of Scientific Research under Contract AF49(638)-1564 and in part by the Office of Naval Research under Contract Nonr 220(50).\n\nPublished - ONEpof68.pdf
Submitted - TR000378.pdf
", "abstract": "It is shown that, if a longitudinal wave is excited in a collision-free plasma and Landau-damps away, and later a second wave is excited and also damps away, then a third wave will spontaneously appear in the plasma. This wave appears long after the first two waves have damped away at a time proportional to the interval between the first two waves, and is in that sense an echo. It is also shown that, if a wave is continuously excited at one point in a plasma and a second wave is continuously excited many Landau damping lengths from the first point, then a third wave will spontaneously appear many Landau damping lengths from the second point. Fundamentally, plasma wave echoes are possible because of the reversible nature of Landau damping. However, small-angle Coulomb collisions are very effective in destroying the echo.", "date": "1968-01", "date_type": "published", "publication": "Physics of Fluids", "volume": "11", "number": "1", "publisher": "American Institute of Physics", "pagerange": "134-142", "id_number": "CaltechAUTHORS:ONEpof68", "issn": "1070-6631", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:ONEpof68", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "AF49(638)-1546" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" } ] }, "other_numbering_system": { "items": [ { "id": "38", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.1063/1.1691746", "primary_object": { "basename": "ONEpof68.pdf", "url": "https://authors.library.caltech.edu/records/qddf6-xjm06/files/ONEpof68.pdf" }, "related_objects": [ { "basename": "TR000378.pdf", "url": "https://authors.library.caltech.edu/records/qddf6-xjm06/files/TR000378.pdf" } ], "resource_type": "article", "pub_year": "1968", "author_list": "O'Neil, T. M. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/xpn1e-y3995", "eprint_id": 94317, "eprint_status": "archive", "datestamp": "2023-08-19 05:49:49", "lastmod": "2023-10-20 17:52:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Echoes in collision-free plasmas", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1967 Elsevier. \n\nReceived 23 August 1967. \n\nThe author is indebted to T. M. O'Neil and J. H. Malmbert for helpful discussions and to the Office of Naval Research for its sponsorship of this research.", "abstract": "It is shown that temporal echoes can occur in collision-free plasmas at various times for different wave number combinations and that spatial echoes can occur at various positions for different frequency combinations.", "date": "1967-10-07", "date_type": "published", "publication": "Physics Letters", "volume": "25", "number": "7", "publisher": "Elsevier", "pagerange": "559-560", "id_number": "CaltechAUTHORS:20190401-114958733", "issn": "0031-9163", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190401-114958733", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.1016/0375-9601(67)90045-x", "resource_type": "article", "pub_year": "1967", "author_list": "Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/54qk0-53408", "eprint_id": 1683, "eprint_status": "archive", "datestamp": "2023-08-21 23:37:08", "lastmod": "2023-10-13 22:56:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "O'Neil-T-M", "name": { "family": "O'Neil", "given": "T. M." } }, { "id": "Malmberg-J-H", "name": { "family": "Malmberg", "given": "J. H." } } ] }, "title": "Plasma Wave Echo", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1967 The American Physical Society \n\nReceived 29 May 1967 \n\nThis researcxh was supported in part by the Office of Naval Research under Contract No. Nonr-220(50), and in part by the Defense Atomic Support Agency under Contract No. DA-49-146-XZ-486.\n\nPublished - GOUprl67.pdf
", "abstract": "It is shown that if a longitudinal wave is excited in a collision-free plasma and Landaudamps away, and a second wave is excited and also damps away, then a third wave (i.e., the echo) will spontaneously appear in the plasma.", "date": "1967-07-31", "date_type": "published", "publication": "Physical Review Letters", "volume": "19", "number": "5", "publisher": "American Physical Society", "pagerange": "219-222", "id_number": "CaltechAUTHORS:GOUprl67", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GOUprl67", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "Nonr-220(50)" }, { "agency": "Defense Atomic Support Agency (DASA)", "grant_number": "DA-49-146-XZ-486" } ] }, "doi": "10.1103/PhysRevLett.19.219", "primary_object": { "basename": "GOUprl67.pdf", "url": "https://authors.library.caltech.edu/records/54qk0-53408/files/GOUprl67.pdf" }, "resource_type": "article", "pub_year": "1967", "author_list": "Gould, R. W.; O'Neil, T. M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3cj4v-80468", "eprint_id": 94213, "eprint_status": "archive", "datestamp": "2023-08-21 23:27:56", "lastmod": "2023-10-20 17:46:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kegel-W-H", "name": { "family": "Kegel", "given": "W. H." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "On the Theory of Pulse Stimulated Radiation from Plasma", "ispublished": "pub", "full_text_status": "public", "keywords": "Cyclotron radiation; plasma radiation; echoes", "note": "\u00a9 1965 Elsevier. \n\nReceived 12 November 1965.\n\nSubmitted - TR000370.pdf
", "abstract": "By including the relativistic mass change in the motion of electrons gyrating in a slightly inhomogeneous field, it is possible to account for the cyclotron echoes observed by Hill and Kaplan.", "date": "1965-12-15", "date_type": "published", "publication": "Physics Letters", "volume": "19", "number": "7", "publisher": "Elsevier", "pagerange": "531-532", "id_number": "CaltechAUTHORS:20190327-120548722", "issn": "0031-9163", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190327-120548722", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" } ] }, "other_numbering_system": { "items": [ { "id": "30", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.1016/0031-9163(65)90760-2", "primary_object": { "basename": "TR000370.pdf", "url": "https://authors.library.caltech.edu/records/3cj4v-80468/files/TR000370.pdf" }, "resource_type": "article", "pub_year": "1965", "author_list": "Kegel, W. H. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1j9pr-t2c04", "eprint_id": 94212, "eprint_status": "archive", "datestamp": "2023-08-21 23:27:26", "lastmod": "2023-10-20 17:46:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Echo Phenomena", "ispublished": "pub", "full_text_status": "public", "keywords": "Plasma radiation; cyclotron resonance; echo phenomena", "note": "\u00a9 1965 Elsevier B. V. \n\nReceived 12 November 1965. \n\nIt is a pleasure to acknowledge discussions with W. H. Kegel and P. E. M. Vandenplas.\n\nAccepted Version - TR000369.pdf
", "abstract": "Due to small nonlinearities, an ensemble of oscillators may exhibit echoes when subjected to multiple pulses of radiation near their resonant frequency. Cyclotron echoes from gyrating charged particles is discussed as an example.", "date": "1965-12-01", "date_type": "published", "publication": "Physics Letters", "volume": "19", "number": "6", "publisher": "Elsevier", "pagerange": "477-478", "id_number": "CaltechAUTHORS:20190327-112251961", "issn": "0031-9163", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190327-112251961", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" } ] }, "other_numbering_system": { "items": [ { "id": "29", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.1016/0031-9163(65)90110-1", "primary_object": { "basename": "TR000369.pdf", "url": "https://authors.library.caltech.edu/records/1j9pr-t2c04/files/TR000369.pdf" }, "resource_type": "article", "pub_year": "1965", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ahk4b-ngc33", "eprint_id": 5351, "eprint_status": "archive", "datestamp": "2023-08-21 23:24:13", "lastmod": "2023-10-16 19:10:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "O'Brien-B", "name": { "family": "O'Brien", "given": "B." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "Parker-J-V", "name": { "family": "Parker", "given": "J." } } ] }, "title": "Longitudinal wave-propagation modes along a positive column", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1965 The American Physical Society. \n\nReceived 20 January 1965. \n\n[R.W.G. was a] National Science Foundation Fellow.\n\nPublished - OBRprl65.pdf
", "abstract": "Measurements have been made of the propagation of waves along the positive column of mercury discharge with characteristic velocities of the order of the speed of sound for the electron gas, (3KT\u2091/m\u2091)^(1/2). These waves have been excited by appropriate couplers, in both dipole and rotationally symmetric modes.", "date": "1965-04-19", "date_type": "published", "publication": "Physical Review Letters", "volume": "14", "number": "16", "publisher": "American Physical Society", "pagerange": "630-632", "id_number": "CaltechAUTHORS:OBRprl65", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:OBRprl65", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Postdoctoral Fellowship" } ] }, "doi": "10.1103/PhysRevLett.14.630", "primary_object": { "basename": "OBRprl65.pdf", "url": "https://authors.library.caltech.edu/records/ahk4b-ngc33/files/OBRprl65.pdf" }, "resource_type": "article", "pub_year": "1965", "author_list": "O'Brien, B.; Gould, R. W.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cm2vz-6k992", "eprint_id": 4828, "eprint_status": "archive", "datestamp": "2023-08-21 23:21:28", "lastmod": "2023-10-16 17:57:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Excitation of ion-acoustic waves", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1964 The American Physical Society. \n\nReceived 11 May 1964. \n\nIt is a pleasure to acknowledge several stimulating conversations with B. D. Fried and with M. Feix concerning this problem. This work has been undertaken as part of the joint research program of the Institut fur Plasmaphysik and EURATOM. This work was done while the author held a National Science Fellowship for research at the Institut fur Plasmaphysik.\n\nPublished - GOUpr64.pdf
", "abstract": "The excitation of ion-acoustic waves by a pair of idealized grids in a collisionless plasma is examined. It is shown that in a limited region, neither too close nor too far from the source, the disturbance closely approximates an exponentially damped (spatially) ion-acoustic wave. Far from the source a weak electron \"wave\" with less damping and larger wavelength dominates; near the source the potential varies as 1/z.", "date": "1964-11-16", "date_type": "published", "publication": "Physical Review", "volume": "136", "number": "4A", "publisher": "American Institute of Physics", "pagerange": "A991-A997", "id_number": "CaltechAUTHORS:GOUpr64", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GOUpr64", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF Postdoctoral Fellowship" } ] }, "doi": "10.1103/PhysRev.136.A991", "primary_object": { "basename": "GOUpr64.pdf", "url": "https://authors.library.caltech.edu/records/cm2vz-6k992/files/GOUpr64.pdf" }, "resource_type": "article", "pub_year": "1964", "author_list": "Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9brx0-87y71", "eprint_id": 34271, "eprint_status": "archive", "datestamp": "2023-08-19 04:48:23", "lastmod": "2023-10-19 14:48:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Vandenplas-P-E", "name": { "family": "Vandenplas", "given": "P. E." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Equations of a hot inhomogeneous plasma model - I: Resonance frequencies of a cylindrical plasma column", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1964 Pergamon Press Ltd. \n\nReceived 28 October 1963. \n\nOne of us (P. V.) thanks Professor M. S. Plesset of the California Institute of Technology for the hospitality granted in his service during the academic year 1959-1960 when he had a Research Fellowship from the lnstitut Interuniversitaires des Sciences Nucleaires of Belgium.\nThe California Institute of Technology enabled him to stay an extra three months in Pasadena by granting him funds of the U.S. Army Signal Research and Development Laboratory.\n\nPublished - VANjnecpp64.pdf
", "abstract": "A system of eight equations with eight unknowns, describing a coherent model of a hot and non-homogeneous cylindrical plasma is established. The model is characterized by a nonconstant electronic equilibrium density, the density gradient being balanced by an electrostatic field. The system of equations reduces to a system of six first-order ordinary linear differential equations with variable coefficients. The tensorial generalization of the initial system is derived. The resonance frequencies of a cylindrical plasma column corresponding to the proposed model is investigated. These frequencies are determined by the method of the scattering cross section of the column relative to a plane homogeneous electromagnetic wave with electric field strength perpendicular to the cylinder axis.", "date": "1964-09", "date_type": "published", "publication": "Journal of Nuclear Energy C", "volume": "6", "number": "5", "publisher": "Pergamon Press", "pagerange": "449-458", "id_number": "CaltechAUTHORS:20120920-133224408", "issn": "0368-3281", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120920-133224408", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Signal Research and Development Laboratory" } ] }, "doi": "10.1088/0368-3281/6/5/301", "primary_object": { "basename": "VANjnecpp64.pdf", "url": "https://authors.library.caltech.edu/records/9brx0-87y71/files/VANjnecpp64.pdf" }, "resource_type": "article", "pub_year": "1964", "author_list": "Vandenplas, P. E. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/e2f52-93d43", "eprint_id": 9954, "eprint_status": "archive", "datestamp": "2023-08-21 23:20:43", "lastmod": "2023-10-16 22:35:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Parker-J-V", "name": { "family": "Parker", "given": "J. V." } }, { "id": "Nickel-J-C", "name": { "family": "Nickel", "given": "J. C." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Resonance oscillations in a hot nonuniform plasma", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1964 American Institute of Physics. \n\nReceived 20 April 1964. \n\nThe authors wish to express their sincere appreciation to the Office of Naval Research for the support of this investigation and to the National Science Foundation for the fellowship held by Mr. Parker during this period.\n\nPublished - PARpof64.pdf
", "abstract": "A quantitative theory of resonance oscillations, such as observed by Dattner and others, is given. The first two moments of the collisionless Boltzmann equation assuming a scalar pressure are used in conjunction with a physically reasonable radial electron density profile to describe the oscillations of a hot nonuniform plasma cylinder. These equations coupled with Maxwell's equations assuming a scalar potential are solved numerically to yield the frequency spectrum of the plasma wave resonances. It is found that the frequency spectrum depends on the parameter r/w2/<\u03bbd^2> where rw is the radius of the plasma column and <\u03bbd^2> is the mean square Debye length of the electron plasma. New experimental observations of dipole and quadrupole spectra for two plasma columns of differing radii are reported and the results of these observations are in good agreement with the theory. The physical mechanism of the resonances is described.", "date": "1964-09", "date_type": "published", "publication": "Physics of Fluids", "volume": "7", "number": "9", "publisher": "American Institute of Physics", "pagerange": "1489-1500", "id_number": "CaltechAUTHORS:PARpof64", "issn": "0031-9171", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:PARpof64", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(13)" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "other_numbering_system": { "items": [ { "id": "24", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.1063/1.1711404", "primary_object": { "basename": "PARpof64.pdf", "url": "https://authors.library.caltech.edu/records/e2f52-93d43/files/PARpof64.pdf" }, "resource_type": "article", "pub_year": "1964", "author_list": "Parker, J. V.; Nickel, J. C.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/jzhv9-bam64", "eprint_id": 5539, "eprint_status": "archive", "datestamp": "2023-08-21 23:17:19", "lastmod": "2023-10-16 19:16:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Swanson-D-G", "name": { "family": "Swanson", "given": "D. G." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "Hertel-R-H", "name": { "family": "Hertel", "given": "R. H." } } ] }, "title": "Experimental study of compressional hydromagnetic waves", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1964 The American Institute of Physics. \n\nReceived 5 August 1963. \n\nThis work was supported by the U. S. Air Force Office of Scientific Research under Grant No. 412-63.\n\nPublished - SWApof64.pdf
", "abstract": "An experiment is described in which a compressional hydromagnetic wave is observed in a hydrogen plasma-filled waveguide. The theory of a cool, partially ionized, resistive plasma in a magnetic field is described briefly and expressions are derived for the dispersion relation and transfer function which include both the propagation and attenuation constants as a function of frequency. Measurements of the cutoff frequency are presented, which verify its linear dependence on the magnetic field, and they show good agreement with theory on the variation with the ion mass density. The impulse response of the plasma is studied, transformed into the frequency domain, and quantitative comparisons are made with the theoretical transfer function to determine the degree of ionization, the resistivity, and the ion-neutral collision frequency.Results indicate that the degree of ionization varies over a range from 75% to 45% when the initial density varies from 1.3 \u00d7 10\u00b2\u00b9 to 1.4 \u00d7 10\u00b2\u00b2 atoms/m\u00b3. The measured resistivity appears to increase with the magnetic field, with the mean value corresponding to a temperature of the order of 5 \u00d7 10\u00b3 \u00b0K. The average value of the product of the charge exchange cross section and the neutral thermal speed is found to be approximately (5.5 \u00b1 1.3) \u00d7 10\u207b\u00b9\u2075 m\u00b3/sec.", "date": "1964-02", "date_type": "published", "publication": "Physics of Fluids", "volume": "7", "number": "2", "publisher": "American Institute of Physics", "pagerange": "269-277", "id_number": "CaltechAUTHORS:SWApof64", "issn": "0031-9171", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:SWApof64", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "412-63" } ] }, "doi": "10.1063/1.1711195", "primary_object": { "basename": "SWApof64.pdf", "url": "https://authors.library.caltech.edu/records/jzhv9-bam64/files/SWApof64.pdf" }, "resource_type": "article", "pub_year": "1964", "author_list": "Swanson, D. G.; Gould, R. W.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/hff07-ah173", "eprint_id": 4178, "eprint_status": "archive", "datestamp": "2023-08-21 23:14:17", "lastmod": "2023-10-16 17:38:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nickel-J-C", "name": { "family": "Nickel", "given": "J. C." } }, { "id": "Parker-J-V", "name": { "family": "Parker", "given": "J. V." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Resonance oscillations in a hot nonuniform plasma column", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1963 The American Physical Society. \n\nReceived 1 July 1963. \n\nWe wish to express our sincere appreciation to the U. S. Office of Naval Research for the support of this investigation.\n\nPublished - NICprl63.pdf
Accepted Version - TR000361.pdf
", "abstract": "This Letter reports new observations of resonances in a low-density plasma column and a quantitative theory of the frequency spectrum which is in excellent agreement with these measurements. Other measurements have recently been reported by Dattner.", "date": "1963-09-01", "date_type": "published", "publication": "Physical Review Letters", "volume": "11", "number": "5", "publisher": "American Physical Society", "pagerange": "183-185", "id_number": "CaltechAUTHORS:NICprl63", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:NICprl63", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(50)" } ] }, "other_numbering_system": { "items": [ { "id": "21", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.1103/PhysRevLett.11.183", "primary_object": { "basename": "NICprl63.pdf", "url": "https://authors.library.caltech.edu/records/hff07-ah173/files/NICprl63.pdf" }, "related_objects": [ { "basename": "TR000361.pdf", "url": "https://authors.library.caltech.edu/records/hff07-ah173/files/TR000361.pdf" } ], "resource_type": "article", "pub_year": "1963", "author_list": "Nickel, J. C.; Parker, J. V.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/c38b8-1q825", "eprint_id": 9815, "eprint_status": "archive", "datestamp": "2023-08-21 23:04:16", "lastmod": "2023-10-16 22:30:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Boyd-G-D", "name": { "family": "Boyd", "given": "G. D." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "Field-L-M", "name": { "family": "Field", "given": "L. M." } } ] }, "title": "Interaction of a Modulated Electron Beam with a Plasma", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1961 IEEE. Reprinted with permission. \n\nReceived by the IRE, August 7, 1961. This work was supported by the Office of Naval Research, Contract NONR 220(13). \n\nA great deal of credit for the success of these experiments is attributable to A.F. Carpenter, whose skill and patience in the fabrication of the glass tubes is gratefully acknowledged. Fruitful discussions were enjoyed with Dr. A.W. Trivelpiece. \n\nThe continuing support of the Office of Naval Research is very gratefully acknowledged.\n\nPublished - BOYprocire61.pdf
Accepted Version - TR000358.pdf
", "abstract": "The results of a theoretical and experimental investigation of the high-frequency interaction of an electron beam with a plasma are reported. An electron beam, modulated at a microwave frequency, passes through a uniform region of a mercury arc discharge after which it is demodulated. Exponentially growing wave amplification along the electron beam was experimentally observed for the first time at a microwave frequency equal to the plasma frequency. Approximate theories of the effects of 1) plasma-electron collision frequencies, 2) plasma-electron thermal velocities and 3) finite beam diameter, are given. In a second experiment the interaction between a modulated electron beam and a slow electrostatic wave on a plasma column has been studied. A strong interaction occurs when the velocity of the electron beam is approximately equal to the velocity of the wave and the interaction is essentially the same as that which occurs in traveling-wave amplifiers, except that here the plasma colum replaces the usual helical slow-wave circuit. The theory predicting rates of growth is presented and compared with the experimental results.", "date": "1961-12", "date_type": "published", "publication": "Proceedings of the IRE", "volume": "49", "number": "12", "publisher": "Institute of Radio Engineers", "pagerange": "1906-1916", "id_number": "CaltechAUTHORS:BOYprocire61", "issn": "0096-8390", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:BOYprocire61", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(13)" } ] }, "other_numbering_system": { "items": [ { "id": "18", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.1109/JRPROC.1961.287719", "primary_object": { "basename": "BOYprocire61.pdf", "url": "https://authors.library.caltech.edu/records/c38b8-1q825/files/BOYprocire61.pdf" }, "related_objects": [ { "basename": "TR000358.pdf", "url": "https://authors.library.caltech.edu/records/c38b8-1q825/files/TR000358.pdf" } ], "resource_type": "article", "pub_year": "1961", "author_list": "Boyd, G. D.; Gould, R. W.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/twmba-2zq30", "eprint_id": 34258, "eprint_status": "archive", "datestamp": "2023-08-19 03:44:35", "lastmod": "2023-10-19 14:48:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "Johnson-C-C", "name": { "family": "Johnson", "given": "C. C." } } ] }, "title": "Coupled Mode Theory of Electron\u2010Beam Parametric Amplification", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1961 The American Institute of Physics. \n\nReceived 19 August 1960.\n\nPublished - GOUjap61.pdf
", "abstract": "A theory of parametric amplification in a filamentary electron beam by transverse fields is developed in coupled mode form. Space charge effects are neglected. In addition to beam modes at the signal frequency, beam modes at frequencies \u03c9\u2099 = \u03c9 + \u03c9\u209a, n = 0, \u00b11, \u00b12\u2026, where \u03c9\u209a is the pump frequency, are coupled together. A discussion of the general form of the equations is given and reveals the circumstances under which exponential gain or periodic energy transfer between various modes can occur. When applied to quadrupole electric pump fields, a description of the quadrupole amplifiers of Adler, Wade, and Gordon is obtained. This theory is then used to evaluate the noise contribution from synchronous beam modes and higher cyclotron idler modes. Coupling by axially symmetric electric fields and by axially symmetric magnetic fields is discussed, and other amplification schemes suggested. The theory of coupling by axially symmetric fields can also be used to study lens effects on noise in the gun region.", "date": "1961-02", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "32", "number": "2", "publisher": "American Institute of Physics", "pagerange": "248-258", "id_number": "CaltechAUTHORS:20120920-094241851", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120920-094241851", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.1735986", "primary_object": { "basename": "GOUjap61.pdf", "url": "https://authors.library.caltech.edu/records/twmba-2zq30/files/GOUjap61.pdf" }, "resource_type": "article", "pub_year": "1961", "author_list": "Gould, R. W. and Johnson, C. C." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/cb9w7-xx484", "eprint_id": 33577, "eprint_status": "archive", "datestamp": "2023-08-19 03:41:33", "lastmod": "2023-10-18 20:26:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Boyd-G-D", "name": { "family": "Boyd", "given": "G. D." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Travelling wave interaction in plasmas", "ispublished": "pub", "full_text_status": "public", "keywords": "plasma physics", "note": "\u00a9 1961 IOP Publishing. \n\nPublished January 1961. \n\nIt is a pleasure to acknowledge valuable discussions with L. M. Field, A. W. Trivelpiece and D. G.Dow and the support of the United States Navy Office of Naval Research in conducting this investigation.\n\nPublished - BOYjnecpp61.pdf
", "abstract": "Interaction between a slow space charge wave which travels along a cylindrical plasma column and an electron beam which passes down the axis of the column is demonstrated experimentally. A spatially growing wave exists when the velocity of the beam is approximately equal to the velocity of the unperturbed wave.", "date": "1961-01", "date_type": "published", "publication": "Journal of Nuclear Energy C", "volume": "2", "number": "1", "publisher": "Pergamon Press Ltd.", "pagerange": "88-89", "id_number": "CaltechAUTHORS:20120827-150113205", "issn": "0368-3281", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20120827-150113205", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" } ] }, "doi": "10.1088/0368-3281/2/1/313", "primary_object": { "basename": "BOYjnecpp61.pdf", "url": "https://authors.library.caltech.edu/records/cb9w7-xx484/files/BOYjnecpp61.pdf" }, "resource_type": "article", "pub_year": "1961", "author_list": "Boyd, G. D. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/myyay-2z182", "eprint_id": 121849, "eprint_status": "archive", "datestamp": "2023-08-21 22:59:31", "lastmod": "2023-10-20 16:18:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fried-Burton-D", "name": { "family": "Fried", "given": "Burton D." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Longitudinal Ion Oscillations in a Hot Plasma", "ispublished": "pub", "full_text_status": "public", "keywords": "General Engineering", "note": "\u00a9 1961 The American Institute of Physics. \n\nThis report was prepared in connection with Space Technology Laboratories Program of General Research. \n\nThe author's are indebted to Dr. Chester Sensenig and Mr. Frank Welsh for assistance with the numerical analysis and machine computations, and to Mrs. Mildred Anderson for the preparation of graphs and line drawings.\n\nPublished - 139_1_online.pdf
", "abstract": "Linearized, longitudinal waves in a hot plasma include, besides the familiar electron plasma oscillations, in which the frequency \u03c9 is of order \u03c9_p = (4\u03c0ne^(2)/m)^(1/2), also ion plasma oscillations with \u03c9 \u2248 \u03c9_p(m/M)^(1/2). The properties of the latter are explored using a Vlasov equation description of the plasma. For equal ion and electron temperatures, T_e = T_i, there exists a discrete sequence of ion oscillations, but all are strongly damped, i.e., have \u2010Im \u03c9/Re \u03c9 \u2a9e 0.5, and hence are not likely to be observable. The ratio Im \u03c9/Re \u03c9 can be made to approach zero (facilitating detection of the waves) by either increasing T_(e)/T_(i) or by producing a current flow in the plasma. In the latter case, Im \u03c9 can even be made positive (corresponding to growing waves), the current required for this being smaller the larger the value of T_(e)/T_(i). This growing wave is just the familiar two\u2010stream instability which is thus seen to be an unstable ion oscillation. It is also noteworthy that the ion oscillations, which for small k have the properties usually associated with an acoustic wave (longitudinal polarization, \u03c9 \u221d k), are obtained using a formalism which is sometimes designated as \"collisionless.\"", "date": "1961", "date_type": "published", "publication": "Physics of Fluids", "volume": "4", "number": "1", "publisher": "American Institute of Physics", "pagerange": "139", "id_number": "CaltechAUTHORS:20230612-708657000.28", "issn": "0031-9171", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230612-708657000.28", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Space Technology Laboratories" } ] }, "doi": "10.1063/1.1706174", "primary_object": { "basename": "139_1_online.pdf", "url": "https://authors.library.caltech.edu/records/myyay-2z182/files/139_1_online.pdf" }, "resource_type": "article", "pub_year": "1961", "author_list": "Fried, Burton D. and Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/6ev7x-2ps38", "eprint_id": 9816, "eprint_status": "archive", "datestamp": "2023-08-21 22:58:41", "lastmod": "2023-10-16 22:30:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Currie-M-R", "name": { "family": "Currie", "given": "M. R." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Coupled-Cavity Traveling-Wave Parametric Amplifiers: Part I -- Analysis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1960 IEEE. Reprinted with permission. \n\nReceived by the IRE, May 3, 1960; revised manuscript received, August 19, 1960. This work was presented at the Seventeenth Annual Conf. on Electron Device Res., Mexico City, Mexico; June, 1959. \n\nThe authors gratefully acknowledge many fruitful discussions with R.D. Weglein and K.P. Grabowski of the Electron Dynamics Department, who contributed greatly to this investigation and carried out the associated experimental program. Thanks are also due B. Fik, who carried out the programming and numerical calculations on an IBM 704 digital computer.\n\nPublished - CURprocire60.pdf
", "abstract": "A general class of traveling-wave parametric amplifiers based on coupled-cavity filter circuits is described. This type of amplifier is particularly suited to microwave frequencies and incorporates new features that overcome some severe difficulties associated with other circuit structures. Traveling-wave diode-type amplifiers having relatively wide bandwidths and great simplicity at S band have already resulted from this approach (details of experiments will be described in Part II). An analysis is presented which provides detailed information on operating characteristics, including the effects of terminal impedances, reflected waves, circuit loss, etc., and also leads to a simple physical picture of the cumulative interaction mechanism in terms of coupled-mode concepts. This physical picture is emphasized throughout this paper. Gain bandwidth considerations are discussed in terms of a fundamental \"interaction-impedance\" parameter. Representative calculated curves show that unilateral gains of 12 to 15 db over relatively wide bandwidths are attainable with as few as 4 to 6 diodes. Methods of increasing the gain through use of ferrites and special circuit techniques are proposed.", "date": "1960-12", "date_type": "published", "publication": "Proceedings of the IRE", "volume": "48", "number": "12", "publisher": "Institution of Radio Engineers", "pagerange": "1960-1973", "id_number": "CaltechAUTHORS:CURprocire60", "issn": "0096-8390", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:CURprocire60", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1109/JRPROC.1960.287564", "primary_object": { "basename": "CURprocire60.pdf", "url": "https://authors.library.caltech.edu/records/6ev7x-2ps38/files/CURprocire60.pdf" }, "resource_type": "article", "pub_year": "1960", "author_list": "Currie, M. R. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/hfhkd-mm296", "eprint_id": 1676, "eprint_status": "archive", "datestamp": "2023-08-21 22:53:21", "lastmod": "2023-10-13 22:56:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Trivelpiece-Alvin-W", "name": { "family": "Trivelpiece", "given": "A. W." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Space Charge Waves in Cylindrical Plasma Columns", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1959 The American Institute of Physics. \n\n(Received February 13, 1959) \n\nThis work was supported in part by the Office of Naval Research. This paper is based partially on a thesis submitted in June, 1958, by one of the authors, Mr. Trivelpiece, to the California Institute of Technology in partial fulfillment of the requirements for the Ph.D. degree.\n\nPublished - TRIjap59.pdf
Accepted Version - TR000353.pdf
", "abstract": "When a plasma is of finite transverse cross section, space-charge waves may propagate even in the absence of a drift motion or thermal velocities of the plasma. Some of the properties of these space charge waves have been investigated by regarding the plasma as a dielectric and solving the resulting field equations. The effect of a steady axial magnetic field is considered, but motion of heavy ions and electron temperature effects are neglected. Waves are found to exist at frequencies low compared with the plasma frequency as well as waves with oppositely directed phase and group velocities (backward waves).Many of the features of these waves have been verified experimentally by measuring phase velocity and attenuation of waves along the positive column of a low pressure mercury arc in an axial magnetic field. Measurements of electron density have been made using these waves and the results are compared with those obtained by other methods. An interesting feature of these measurements, of value in plasma diagnostics, is that they can be made with frequencies which are small compared with the plasma frequency.", "date": "1959-11", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "30", "number": "11", "publisher": "American Institute of Physics", "pagerange": "1784-1793", "id_number": "CaltechAUTHORS:TRIjap59", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:TRIjap59", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(13)" } ] }, "other_numbering_system": { "items": [ { "id": "13", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.1063/1.1735056", "primary_object": { "basename": "TR000353.pdf", "url": "https://authors.library.caltech.edu/records/hfhkd-mm296/files/TR000353.pdf" }, "related_objects": [ { "basename": "TRIjap59.pdf", "url": "https://authors.library.caltech.edu/records/hfhkd-mm296/files/TRIjap59.pdf" } ], "resource_type": "article", "pub_year": "1959", "author_list": "Trivelpiece, A. W. and Gould, R. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/m56g4-qt698", "eprint_id": 9819, "eprint_status": "archive", "datestamp": "2023-08-21 22:50:21", "lastmod": "2023-10-16 22:30:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Traveling-Wave Couplers for Longitudinal Beam-Type Amplifiers", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1959 Institute of Radio Engineers. Reprinted with permission. \n\nOriginal manuscript received by the IRE, August 25, 1958; revised manuscript received, December 19, 1958. The research on microwave electronics was supported by the Office of Naval Research and the Sperry Rand Corporation. \n\nThe author wishes to express his sincere appreciation to D.C. Forster for several illuminating discussions of this problem, to K. Hebert for writing the program for machine computation of the matrix elements, and to K. Lock for obtaining the differential analyzer solutions.\n\nPublished - GOUprocire59.pdf
", "abstract": "The equations governing traveling-wave interaction between an electron beam and a slow-wave circuit are formulated in terms of amplitudes of circuit mode and slow and fast space charge modes. The resulting equations are solved to find expressions for the matrix which relates the mode amplitudes at the output of the traveling-wave coupler to the mode amplitudes at the input. The properties of this matrix are discussed and numerical values given for Kompfner Dip. Matrices for velocity jumps and drift regions are also given, and the characteristics of couplers which are preceded by or followed by a drift region and velocity jump are discussed. It is shown that necessary and sufficient conditions for the removal of beam noise from the fast space-charge wave by any lossless coupler are that, for a circuit input, there be no circuit output (M\u2081\u2081 = 0) and no slow space-charge wave output (M\u2082\u2081 = 0). These results are then applied to the design of fast space-charge wave couplers for longitudinal beam type parametric amplifiers.", "date": "1959-03", "date_type": "published", "publication": "Proceedings of the IRE", "volume": "47", "number": "3", "publisher": "Institute of Radio Engineers", "pagerange": "419-426", "id_number": "CaltechAUTHORS:GOUprocire59", "issn": "0096-8390", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GOUprocire59", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" }, { "agency": "Sperry Rand Corporation" } ] }, "primary_object": { "basename": "GOUprocire59.pdf", "url": "https://authors.library.caltech.edu/records/m56g4-qt698/files/GOUprocire59.pdf" }, "resource_type": "article", "pub_year": "1959", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2qawf-9jf66", "eprint_id": 93188, "eprint_status": "archive", "datestamp": "2023-08-21 22:48:41", "lastmod": "2024-01-14 21:35:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } }, { "id": "Trivelpiece-Alvin-W", "name": { "family": "Trivelpiece", "given": "A. W." } } ] }, "title": "Electro-Mechanical Modes in Plasma Waveguides", "ispublished": "pub", "full_text_status": "public", "keywords": "Equivalent circuits; plasma; waveguides", "note": "\u00a9 1958 IEE. \n\n{The paper was first received 19th February, and in revised form 11th April, 1958. It was presented at the International Convention on Microwave Valves, 20th May, 1958.) \n\nThe research described herein was conducted under Contract Nonr-220(13) with the United States Navy, Office of Naval Research, and all rights granted to the U.S. Government under that contract are hereby reserved.\n\nPublished - TR000349.pdf
", "abstract": "In addition to increasing the cut-off frequencies of TM-modes in a waveguide, the introduction of a plasma column into the waveguide also introduces new modes of propagation. The properties of these modes, including the effect of an axial d.c. magnetic field but neglecting ion motion, have been studied by solving the field equations considering the electron plasma as a dielectric. The new modes generally have phase velocities much less than the velocity of light; one type exists down to zero frequency and another type is a backward wave. Neither the metallic conductor nor the axial magnetic field is essential to the existence of slow modes. Angular-dependent modes can exhibit Faraday rotation of polarization. \n\nA qualitative explanation of these modes is given in terms of an equivalent electrical circuit for the transmission line. Many of the properties of these modes have been verified experimentally by measuring phase velocity of waves along a mercury-arc discharge in an axial magnetic field. These modes are closely related to space- charge waves in electron beams, and several interesting microwave applications arc suggested.", "date": "1958-11", "date_type": "published", "publication": "Proceedings of the IEE - Part B: Radio and Electronic Engineering", "volume": "105", "number": "10", "publisher": "Institution of Electrical Engineers", "pagerange": "516-519", "id_number": "CaltechAUTHORS:20190222-150415098", "issn": "0534-2791", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190222-150415098", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "220(13)" } ] }, "other_numbering_system": { "items": [ { "id": "9", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.1049/pi-b-1.1958.0092", "primary_object": { "basename": "TR000349.pdf", "url": "https://authors.library.caltech.edu/records/2qawf-9jf66/files/TR000349.pdf" }, "resource_type": "article", "pub_year": "1958", "author_list": "Gould, R. W. and Trivelpiece, A. W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ytgtg-58823", "eprint_id": 9820, "eprint_status": "archive", "datestamp": "2023-08-21 22:47:02", "lastmod": "2023-10-16 22:30:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Characteristics of traveling-wave tubes with periodic circuits", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1958 IEEE. Reprinted with permission. \n\nManuscript received by the PGED, November 11, 1957. This work was done while the author was at the Hughes Res. and Dev. Labs., Culver City, Calif. \n\nIt is a pleasure to acknowledge the interest and suggestions of members of the Electron Tube Laboratory of the Hughes Research and Development Laboratories, particularly L.M. Field and S. Sensiper. The numerical results were obtained by E.A. Mazzari and J. Pochares, of the Hughes Systems Analysis Laboratory, using an IBM 650 digital computer. The author is deeply grateful for their considerable contribution to this study.\n\nPublished - GOUiretransed58.pdf
", "abstract": "An analysis of an electron beam which interacts with a chain of coupled resonators is presented. Several important characteristics of traveling-wave tubes which employ periodic slow-wave circuits are described. It is found that, even for a lossless circuit, the gain does not become large near either pass band edge although the interaction impedance does become very large. Furthermore, useful amplification is found to occur outside the normal circuit pass band, particularly when the frequency is below the low-frequency cutoff where the circuit presents an inductive reactance to the beam. The problem of matching uniform transmission lines to the periodic circuit is discussed from the equivalent circuit point of view and it is shown that the terminating impedance which produces no reflection from the output end of the circuit when the beam is present may be appreciably different from that required when the beam is absent. The method of analysis applies to spatial harmonic operation, including backward spatial harmonics, as well as to synchronously tuned multicavity klystrons.", "date": "1958-07", "date_type": "published", "publication": "IRE Transactions on Electron Devices", "volume": "5", "number": "3", "publisher": "Institution of Radio Engineers", "pagerange": "186-195", "id_number": "CaltechAUTHORS:GOUireted58", "issn": "0096-2430", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GOUireted58", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "primary_object": { "basename": "GOUiretransed58.pdf", "url": "https://authors.library.caltech.edu/records/ytgtg-58823/files/GOUiretransed58.pdf" }, "resource_type": "article", "pub_year": "1958", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/30nc1-4dj54", "eprint_id": 3009, "eprint_status": "archive", "datestamp": "2023-08-21 22:45:45", "lastmod": "2023-10-16 15:33:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Boyd-G-D", "name": { "family": "Boyd", "given": "G. D." } }, { "id": "Field-L-M", "name": { "family": "Field", "given": "L. M." } }, { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "Excitation of plasma oscillations and growing plasma waves", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1958 The American Physical Society. \n\nReceived 22 November 1957. \n\nWork supported by the Office of Naval Research.\n\nPublished - BOYpr58.pdf
", "abstract": "Recent work in our laboratory has been concerned with the experimental verification of plasma interaction theories (1-3) which predict spatially growing waves in a plasma which is traversed by a beam of fast-charged particles. The growing wave results from the excitation of oscillations of the plasma electrons by the beam and the interaction of the oscillating electrons back on the beam.", "date": "1958-02-15", "date_type": "published", "publication": "Physical Review", "volume": "109", "number": "4", "publisher": "American Physical Society", "pagerange": "1393-1394", "id_number": "CaltechAUTHORS:BOYpr58", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:BOYpr58", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" } ] }, "doi": "10.1103/PhysRev.109.1393", "primary_object": { "basename": "BOYpr58.pdf", "url": "https://authors.library.caltech.edu/records/30nc1-4dj54/files/BOYpr58.pdf" }, "resource_type": "article", "pub_year": "1958", "author_list": "Boyd, G. D.; Field, L. M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9hfb3-0z737", "eprint_id": 92964, "eprint_status": "archive", "datestamp": "2023-08-19 02:57:41", "lastmod": "2024-01-14 21:28:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "Roy W." } } ] }, "title": "Space Charge Effects in Beam\u2010Type Magnetrons", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1957 The American Institute of Physics. \n\nThe author wishes to express his appreciation for the helpful discussions with his associates, Professor Lester M. Field and James W. Sedin. Dr. J. Warga and D. Rubin of the mathematics department of the Electrodata Corporation and Iwao Sugai contributed the numerical solutions presented here. This work was carried out as part of a program of research in the field of microwave electronics which is supported by the Office of Naval Research. It is a pleasure to acknowledge this general support as well as a grant from the Sperry Gyroscope Company which made possible the computational results described in Sec. V.\n\nPublished - TR000345.pdf
", "abstract": "A theoretical treatment of space charge effects in beam\u2010type magnetron amplifiers and oscillators is given. It is assumed that the beam is relatively thin and that the magnetic field is large. The \"cyclotron waves\" are not treated. A space charge parameter appears in this theory of magnetron\u2010type traveling\u2010wave interaction in a manner which is analogous to the manner in which QC appears in ordinary traveling\u2010wave interaction. A distinctive feature of the space charge waves in the magnetron case is that one increases along the beam and the other decreases along the beam. A simple physical explanation of this effect is given.\n\nThis theory is then used to determine the starting conditions of an M\u2010type backward wave oscillator. It is found that when the tube is long in space charge wavelengths there is an appreciable reduction of starting current. When the space charge parameter approaches zero, the solutions found here reduce to the usual two\u2010wave solutions.", "date": "1957-06", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "28", "number": "5", "publisher": "American Institute of Physics", "pagerange": "599-605", "id_number": "CaltechAUTHORS:20190215-170644832", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190215-170644832", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" }, { "agency": "Sperry Gyroscope Company" } ] }, "other_numbering_system": { "items": [ { "id": "5", "name": "Electron Tube and Microwave Laboratory Technical Report" } ] }, "local_group": { "items": [ { "id": "Electron-Tube-and-Microwave-Laboratory" } ] }, "doi": "10.1063/1.1722810", "primary_object": { "basename": "TR000345.pdf", "url": "https://authors.library.caltech.edu/records/9hfb3-0z737/files/TR000345.pdf" }, "resource_type": "article", "pub_year": "1957", "author_list": "Gould, Roy W." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1gp7s-74422", "eprint_id": 9818, "eprint_status": "archive", "datestamp": "2023-08-21 22:37:06", "lastmod": "2023-10-16 22:30:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gould-R-W", "name": { "family": "Gould", "given": "R. W." } } ] }, "title": "A coupled mode description of the backward\u2013wave oscillator and the Kompfner dip condition", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1955 IEEE. Reprinted with permission. \n\nOriginal manuscript received by the PGED, February, 1955. This work was supported by a Howard Hughes Fellowship in Science and Engineering. \n\nThe author wishes to thank Dr. Charles K. Birdsall of the Hughes Research and Development Laboratories and Professor Lester M. Field of the California Institute of Technology for their valuable suggestions\n\nPublished - GOUiretransed55.pdf
", "abstract": "The start oscillation condition for the backward-wave oscillator and the operation of the traveling-wave tube amplifier at the Kompfner dip point are described from the point of view of the coupling of two modes of propagation. Growing waves are not involved. Two waves are sufficient when the tube is more than a half plasma wavelength long. Operation in this \"large space charge\" domain is inherently simpler than in the \"low space charge\" domain. The start oscillation condition and the Kompfner dip condition are simply expressed in terms of the coupling constant between modes, HL = (2n \u00b1 1) \u03c0/2, where n is an integer. In addition, the uncoupled modes must have the same velocity. The result is also expressed in terms of the more familiar parameters CN and hL. The effect of loss in the circuit mode is calculated. When the two waves carry energy in opposite directions, growing waves result. This case is discussed briefly.", "date": "1955-10", "date_type": "published", "publication": "IRE Transactions on Electron Devices", "volume": "2", "number": "4", "publisher": "Institution of Radio Engineers", "pagerange": "1955-1991", "id_number": "CaltechAUTHORS:GOUireted55", "issn": "0096-2430", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:GOUireted55", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Hughes Research Laboratories" } ] }, "primary_object": { "basename": "GOUiretransed55.pdf", "url": "https://authors.library.caltech.edu/records/1gp7s-74422/files/GOUiretransed55.pdf" }, "resource_type": "article", "pub_year": "1955", "author_list": "Gould, R. W." } ]