[ { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/74ywt-9pa32", "eprint_id": 51234, "eprint_status": "archive", "datestamp": "2023-08-19 02:21:07", "lastmod": "2023-10-18 16:12:55", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Duwez-P", "name": { "family": "Duwez", "given": "Pol" } }, { "id": "Wittry-D-B", "name": { "family": "Wittry", "given": "David B." } } ] }, "title": "Design and Development of an Electronic X-Ray Probe for the Study of Alloys and of the Structure of Metals", "ispublished": "unpub", "full_text_status": "public", "note": "\u00a9 1954 California Institute of Technology.\n\nINTERIM TECHNICAL REPORT NO. 1 under\nDEPARTMENT of the ARMY Contract DA-04-495-Ord-463\nD/A Project No. 593-08-024 Ord. Project No. TB4-161A.\n\n
Submitted - DUMitr1-54.pdf
", "abstract": "Progress on the design and development of an\nelectronic x-ray microprobe for quantitative\nand qualitative composition measurements of\nabout 1 cubic micron of the surface of metals\nand alloys is described in this report. The\nprinciple is that first used by Castaing, in\nwhich the metal is subjected to bombardment\nby a finely focused probe of electrons and the\nelements present and their proportions are\ndetermined by an analysis of the frequency and\nintensity of the characteristic x-rays emitted.\nWith the first model of the instrument, it will\nbe possible to study the elements in the ranges\nof atomic numbers 19 through 34 and 50 through\n84. This report omits any theoretical treatment\nof the effects of heat generated in the sample,\nfluorescence radiation, or a detailed discussion\nof the corrections that must be made. These\nmatters will be considered in a later report.", "date": "2014-11-04", "date_type": "published", "publisher": "California Institute of Technology", "id_number": "CaltechAUTHORS:20141104-113749673", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141104-113749673", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of the Army", "grant_number": "DA-04-495-Ord-463" } ] }, "collection": "CaltechAUTHORS", "primary_object": { "basename": "DUMitr1-54.pdf", "url": "https://authors.library.caltech.edu/records/74ywt-9pa32/files/DUMitr1-54.pdf" }, "resource_type": "monograph", "pub_year": "2014", "author_list": "DuMond, Jesse W. M.; Duwez, Pol; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/t4xya-wdg43", "eprint_id": 48438, "eprint_status": "archive", "datestamp": "2023-08-19 02:27:25", "lastmod": "2023-10-17 19:21:14", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Final Report", "ispublished": "unpub", "full_text_status": "public", "note": "Published - N6_onr_-_244,_Task_Oder_IV.pdf
", "abstract": "This final report on Contract N6onr - 244, Task Order IV,\n(NR 017-602), covering the period from its beginning, March 1, 1947,\nto its termination, November 30 1954, includes a brief discussion\nof the entire research carried out under its auspices . References\nare made to a bibliography which includes all Special Technical\nReports and published articles pertaining to accomplishments of\nthis Task.\n\nWork financed by other organizations is referred to in\nthis report wherever this work has been instrumental in the pursuit\nof the objectives of the Task.", "date": "2014-08-12", "date_type": "published", "publisher": "Caltech Library", "id_number": "CaltechAUTHORS:20140812-144902709", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140812-144902709", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "NR 017-602" }, { "agency": "Research Corporation" }, { "agency": "Atomic Energy Commission" }, { "agency": "Office of Ordnance Research, U.S. Army" } ] }, "primary_object": { "basename": "N6_onr_-_244,_Task_Oder_IV.pdf", "url": "https://authors.library.caltech.edu/records/t4xya-wdg43/files/N6_onr_-_244,_Task_Oder_IV.pdf" }, "resource_type": "monograph", "pub_year": "2014", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/sndg0-ma351", "eprint_id": 46562, "eprint_status": "archive", "datestamp": "2023-08-19 01:53:56", "lastmod": "2023-10-20 23:27:56", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shenfil-L", "name": { "family": "Shenfil", "given": "Leon" } }, { "id": "Danielson-W-E", "name": { "family": "Danielson", "given": "Warren E." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "A Point Focusing Monochromator for the Study of Low-Angle X-Ray Diffraction: Determining the Size Distributions of Carbon Blacks and a Precision Determination of the Size of Dow Latex Particles", "ispublished": "unpub", "full_text_status": "public", "note": "I wish to take this opportunity to thank Professor\nJesse W.M. DuMond for suggesting this thesis project and\nfor taking a keen interest in the course of its development.\nHis helpful suggestions have been instrumental in the success\nof this work. In the three years that I have worked for him\nas a graduate student, I have profited considerably from his\nvast experience and have learned a good deal of the practical\nside of physics, the sort of thing one does not find in textbooks.\nFor this, I wish to express my deepest gratitude.\nTo Warren E. Danielson, who shares equally in the design\nand construction of the point focusing monochromator, I wish\nto extend my hearty thanks and the hope that he will find\nmany interesting applications of the instrument.\nThis project was supported jointly by the Office of Naval\nResearch and the Atomic Energy Commission.\nLeon Shenfil\n\nThe undersigned wishes to take this opportunity to express\nhis gratitude to the Office of Naval Research for their generous\npermission to include financing of this development under Contract\nN6onr-244, T.O. IV. He also wishes to thank Prof. L. Pauling for\nhis encouragement and supporting recommendation of the proposal\nto the O.N.R. when the primary idea was in a nascent stage. He\nis very deeply indebted to the two graduate students whose\npatience, skill and diligence have so successfully brought the\ninitial ideas to concrete realization in spite of many d1fficulties\nand uncertainties.\nRespectfully submitted,\nJesse W. M. DuMond\n\nFundamental Research in Spectroscopy of Short Wave-Length X-Rays and Gamma Rays.\n\nAccepted Version - A_Point_Focusing_Monochromator_for_the_Study_of_Low-Angle_X-ray_Diffraction.pdf
", "abstract": "A point focusing x-ray monochromator was designed and\nconstructed for low angle scattering studies. The anastigmatic\npoint focus is achieved by means of two cylindrically bent\nquartz crystals whose focal circles are mutually perpendicular. The beam, emanating from the copper target of an x-ray tube, is reflected in succession, first from the crystal defining the horizontal focal circle and, second from the crystal defining\nthe vertical focal circle following which it comes to a mono\nchromatic point focus of wavelength 1.537 A (Cu Ko(1). The sample to be studied is placed between the second crystal and the point focus, and the scattered beam is detected by means of a photographic plate placed at the point focus, at right angles to the undeviated beam, the latter being suppressed by means of an absorber.\n\nMathematical analysis, in which a ray was traced through\nthe two crystal system, revealed correctly the shape and size\nof the point focus, and the possibility of reducing the latter\nin size by stopping down the beam emerging from the target.\n\nThe instrument and its lining up procedure is described\nin detail, particularly the latter since the orientation of the two crystals relative to each other and the x-ray tube involve twelve degrees of freedom.\n\nSuggestions for improving the intensity of the instrument\nare made . These consist of (1) substitution of topaz crystals\nfor quartz, (2) use of helium atmosphere instead of air to\nsurround the x-ray beam (3) reorientation of the x-ray tube\nto permit smaller angles of emergence of the beam.\n\nAs a trial run for the instrument, the scattering\npatterns of two kinds of carbon black (good scatterers) were\nobtained from which the average particle sizes and size\ndistributions were calculated.", "date": "2014-07-08", "date_type": "published", "publisher": "Caltech Library", "id_number": "CaltechAUTHORS:20140629-201517483", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140629-201517483", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N6onr-244" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "NR 017-602" }, { "agency": "Atomic Energy Commission" } ] }, "collection": "CaltechAUTHORS", "primary_object": { "basename": "A_Point_Focusing_Monochromator_for_the_Study_of_Low-Angle_X-ray_Diffraction.pdf", "url": "https://authors.library.caltech.edu/records/sndg0-ma351/files/A_Point_Focusing_Monochromator_for_the_Study_of_Low-Angle_X-ray_Diffraction.pdf" }, "resource_type": "monograph", "pub_year": "2014", "author_list": "Shenfil, Leon; Danielson, Warren E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/68h6x-p7c90", "eprint_id": 46560, "eprint_status": "archive", "datestamp": "2023-08-19 02:49:35", "lastmod": "2023-10-26 19:50:24", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "Henrikson-H-E", "name": { "family": "Henrikson", "given": "H. E." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "The Design, Construction, and Performance of a Magnetic Focusing, Semi-Circular, Low Energy Beta-Ray Spectrometer", "ispublished": "unpub", "full_text_status": "public", "note": "", "abstract": "A semi-circular beta-ray spectrometer (Fig. 1) has been constructed\nfor operation between 2 and 120 kev electron energy. This\ninstrument was designed to supplement the ring- focusing beta-ray spectrometer\nwhose lower limit is approximately 25 kev. The 180\u00b0\nspectrometer has an electron trajectory radius of 12 cm. The field is\nproduced by two iron free coils spaced to give a nearly homogeneous\nfield (with some second order focusing) in the region of the electron\ntrajectories . The field current is supplied by a one kw motor- generator\nset. Stabilization is obtained to 2 parts in 10, 000 with a rotating electro- mechanical unit and an electronic servo system. Source and\nGeiger counter window dimensions for a standard resolution of 0 .8% are 0.1 cm x 4 cm. With a 10 \u03bc.g/cm^2 formvar window, transmission is assured\ndown to 2 kev electron energy. A recording potentiometer traces the\ncounting rate vs. electron energy. Several examples of chart recordings\nare reproduced to illustrate the performance of the semi- circular beta-ray\nspectrometer.", "date": "2014-07-01", "date_type": "published", "publisher": "Caltech Library", "id_number": "CaltechAUTHORS:20140629-192312570", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140629-192312570", "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)-63" } ] }, "primary_object": { "basename": "The_Design,_Construction_and_Performance_of_a_Magnetic_Focusing,_Semi-Circular,_Low_Energy_Beta-Ray_Spectrometer.pdf", "url": "https://authors.library.caltech.edu/records/68h6x-p7c90/files/The_Design,_Construction_and_Performance_of_a_Magnetic_Focusing,_Semi-Circular,_Low_Energy_Beta-Ray_Spectrometer.pdf" }, "resource_type": "monograph", "pub_year": "2014", "author_list": "Henrikson, H. E. and DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/h5fj4-6gj09", "eprint_id": 46561, "eprint_status": "archive", "datestamp": "2023-08-19 02:21:44", "lastmod": "2023-10-26 19:50:26", "type": "monograph", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "The Spectroscopy of Nuclear Gamma-Rays by Direct Crystal Diffraction Methods", "ispublished": "unpub", "full_text_status": "public", "note": "A report on fundamental research in precision spectroscopy of x-rays and gamma-rays conducted under contract beginning March 1947 with the Office of Naval Research, financially assisted by the Atomic Energy Commission funds and since October 1952 under direct contract with the Atomic Energy Commission.\n\nSubmitted - The_Spectroscopy_of_Nuclear_Gamma-Rays_By_Direct_Crystal_Diffraction_Methods__1954.pdf
", "abstract": "This report contains the first comprehensive account of a new\ntechnique developed at the California Institute of Technology (and\nto date duplicated nowhere else) for the measurement, with high\nabsolute precision, by means of a focusing curved crystal diffraction\nspectrometer, of the wavelengths and energies of gamma-rays from\nnatural and artificial emitters over a wide range of quantum energies\nfrom 1.3 Mev (wavelength, 9 x-units) to 25 kev (wavelength 500 x-units).", "date": "2014-07-01", "date_type": "published", "publisher": "Caltech Library", "id_number": "CaltechAUTHORS:20140629-194734577", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140629-194734577", "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)-8" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "NR 017-602" } ] }, "collection": "CaltechAUTHORS", "primary_object": { "basename": "The_Spectroscopy_of_Nuclear_Gamma-Rays_By_Direct_Crystal_Diffraction_Methods__1954.pdf", "url": "https://authors.library.caltech.edu/records/h5fj4-6gj09/files/The_Spectroscopy_of_Nuclear_Gamma-Rays_By_Direct_Crystal_Diffraction_Methods__1954.pdf" }, "resource_type": "monograph", "pub_year": "2014", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/yctg2-gkv35", "eprint_id": 46411, "eprint_status": "archive", "datestamp": "2023-08-19 05:08:06", "lastmod": "2023-10-26 19:43:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Pilgrims' progress in search of the fundamental constants", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1965 American Institute of Physics.\n\nPublished - 1.3046944.pdf
", "abstract": "The practice of making broadly inclusive surveys, from time to time, of the status of our knowledge of the fundamental constants of physics and chemistry may be said to have started with a famous paper by Raymond T. Birge, of Berkeley, published in Reviews of Modem Physics in 1929. To Professor Birge, also, is due the credit for being the first, as far as I know, to apply the method of least squares in order to determine most probable values of three of the constants; e, the electronic charge m, the electron rest mass; and h, Planck's constant, using a highly overdetermined set of experimental data on functions of these three quantities.\n\nThe fundamental constants of nature are so interrelated that a measurement affecting one affects them all. The author became interested when Millikan's oil\u2010drop value of the electron charge was different from the value given by x\u2010ray determination of crystal spacings. To assist in finding the true values, he invented a method for plotting various functions of the constants in a space of as many coordinates as there are constants. If all measurements are consistent, the plotted functions intersect in a point. When they do not intersect, one examines standard deviations, which correspond to thicknesses of surfaces, in an effort to find out what is wrong. In three decades, searches of this kind have reduced uncertainties in the constants from a fraction of a percent to, at most, tens of parts per million.", "date": "1965-10", "date_type": "published", "publication": "Physics Today", "volume": "18", "number": "10", "publisher": "American Institute of Physics", "pagerange": "26-43", "id_number": "CaltechAUTHORS:20140621-114904849", "issn": "0031-9228", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-114904849", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.3046944", "primary_object": { "basename": "1.3046944.pdf", "url": "https://authors.library.caltech.edu/records/yctg2-gkv35/files/1.3046944.pdf" }, "resource_type": "article", "pub_year": "1965", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/x839h-5cw58", "eprint_id": 6180, "eprint_status": "archive", "datestamp": "2023-08-21 23:00:25", "lastmod": "2023-10-16 20:10:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Absence of Dispersive Properties of Space for Electromagnetic Radiation Tested to \u00b1 14 x 10^-5; Comments on a Proposal of Softky and Squire", "ispublished": "pub", "full_text_status": "public", "note": "Copyright \u00a9 1961 by the National Academy of Sciences \n\nCommunicated January 17, 1961 \n\nWork performed under the auspices of the U.S. Atomic Energy Commission.", "abstract": "In session I 1 of the Berkeley meeting of December 30, 1960, S. D. Softky and R. K. Squire proposed a test for dispersive properties of space for electromagnetic radiation by detonating a nuclear explosive at a distance of 10^6 miles from the earth and noting the arrival times of different types of radiation at detectors above the atmosphere. The purpose of this note is to point out that Softky and Squire have overlooked the fact that a test for the dispersive properties they postulate already exists, covering perhaps not quite as extensive a range of the electromagnetic spectrum as they hope to cover (they claim a factor of 10^11) but nevertheless sufficient to render any such effect extremely unlikely over a range of frequencies of a factor of 5 X 10^9. I refer to a measurement performed in 1950 by means of the bent quartz crystal diffraction spectrometer [1] of the wavelength of the annihilation radiation generated in a block of copper by positrons from the nuclide 64Cu.", "date": "1961-03-01", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "47", "number": "3", "publisher": "National Academy of Sciences", "pagerange": "347-348", "id_number": "CaltechAUTHORS:DUMpnas61", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpnas61", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "primary_object": { "basename": "DUMpnas61.pdf", "url": "https://authors.library.caltech.edu/records/x839h-5cw58/files/DUMpnas61.pdf" }, "resource_type": "article", "pub_year": "1961", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ncd3y-etz76", "eprint_id": 4460, "eprint_status": "archive", "datestamp": "2023-08-21 22:51:57", "lastmod": "2023-10-16 17:46:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "A survey of our present sources of information on the conversion constant, \u039b(=\u03bbg/\u03bbs) and the absolute wavelengths of x-ray emission lines", "ispublished": "pub", "full_text_status": "public", "note": "Copyright \u00a9 1959 by the National Academy of Sciences. \n\nCommunicated May 4, 1959.", "abstract": "Origin of the \"X-Unit\" and the Scale of X-Ray Wavelengths. - The wavelengths of X-ray emission lines measured relative to each other by the high precision methods of crystal diffraction are mostly known with a precision of 1 part in 10^(4) to 10^(5). By refined and very careful measurements with the 2-crystal spectrometer, an imprecision approaching and in some cases perhaps even smaller than a part in a million can be obtained.", "date": "1959-07-01", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "45", "number": "7", "publisher": "National Academy of Sciences", "pagerange": "1052-1080", "id_number": "CaltechAUTHORS:DUMpnas59", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpnas59", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "primary_object": { "basename": "DUMpnas59.pdf", "url": "https://authors.library.caltech.edu/records/ncd3y-etz76/files/DUMpnas59.pdf" }, "resource_type": "article", "pub_year": "1959", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dgkh0-6p129", "eprint_id": 46458, "eprint_status": "archive", "datestamp": "2023-08-19 03:12:59", "lastmod": "2023-10-26 19:45:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cohen-E-R", "name": { "family": "Cohen", "given": "E. R." } }, { "id": "Crowe-K-M", "name": { "family": "Crowe", "given": "K. M." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "J. W. M." } }, { "id": "Beth-R-A", "name": { "family": "Beth", "given": "Richard A." } } ] }, "title": "Fundamental Constants of Physics [Book Review]", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1959 American Association of Physics Teachers.\n\nPublished - 1.1934755.pdf
", "abstract": "Book review of: Fundamental Constants of Physics. E. R. COHEN, K. M.\nCROWE, AND J. W. M. DuMOND. Pp. 287+ix. Interscience\nMonographs in Physics and Astronomy,\nVolume I. Interscience Publishers, Inc., New York,\n1957.", "date": "1959-01", "date_type": "published", "publication": "American Journal of Physics", "volume": "27", "number": "1", "publisher": "American Association of Physics Teachers", "pagerange": "63-64", "id_number": "CaltechAUTHORS:20140624-081843163", "issn": "0002-9505", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-081843163", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1119/1.1934755", "primary_object": { "basename": "1.1934755.pdf", "url": "https://authors.library.caltech.edu/records/dgkh0-6p129/files/1.1934755.pdf" }, "resource_type": "article", "pub_year": "1959", "author_list": "Cohen, E. R.; Crowe, K. M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/wxma0-y1992", "eprint_id": 46644, "eprint_status": "archive", "datestamp": "2023-08-19 03:11:07", "lastmod": "2023-10-26 19:54:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Gamma-Ray Spectroscopy by Direct Crystal Diffraction", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 1958 Annual Reviews.\nThe survey of literature pertaining to this review was completed in March, 1958.\nAll the work described herein was performed either under the auspices of the\nU. S. Atomic Energy Commission or under contracts supported by that agency.", "abstract": "With the exception of certain early work with flat crystals by Rutherford\n& Andrade (1) and by Frilley (2), to date, crystal diffraction \u03b3-ray spectroscopy\nhas been accomplished almost entirely by means of transmission-type\nspectrometers using bent quartz crystal focusing. In this type of instrument,\nwhose first conception was published in 1930 by DuMond & Kirkpatrlck\n(3), a thin cylindrical lamina of quartz of uniform thickness is bent so that\nits neutral plane, initially a right circular cylinder of radius 2R, assumes the\nform of a right circular cylinder of radius R. (By the \"neutral plane\" is\nmeant that plane through the center of the thickness of the crystalline\nlamina which undergoes neither compression nor elongation when bending\noccurs.) The lamina is cut from the original unstressed crystal lattice so that\nthe planes to be used in the selective reflection are made to converge after\nbending in such fashion that, if prolonged, they would all intersect in a common\nline distant 2R from the center of the lamina. Figure 1 illustrates the\nlamina, seen on edge, before and after bending, with lines indicating the\ndirection of the atomic planes. These planes, after bending, converge in a\nline represented in projection by the point \u03b2. Confining ourselves to two\ndimensions, the normal projection of the neutral plane and the point \u03b2 define\nthe \"focal circle,\" which is the locus of focal points R_ \u03bb for radiations of different\nwavelength selectively reflected by the planes of the crystal in accord\nwith Bragg's law, n\u03bb = 2d sin \u03b8. In Figure 1 the thickness and the aperture\nangle, \u03b1, are greatly exaggerated. Cauchois has pointed out that the compression\nand dilation of the lattice constant, incident to bending, result in\nfront-to-back focusing as well as side-to-side focusing, within the confines of\nHooke's law, so that the crystal behaves as though all selective reflection\noccurred on the neutral plane. It can also be easily shown that for selective\nreflection in transmission by planes normal to the lamina, the correction to Bragg's law for crystalline refractive index diltering from unity vanishes\nexactly. This is explained in more detail in Reference 6, p. 241.", "date": "1958-12", "date_type": "published", "publication": "Annual Review of Nuclear Science", "volume": "8", "publisher": "Annual Reviews", "pagerange": "163-180", "id_number": "CaltechAUTHORS:20140702-140059190", "issn": "0066-4243", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140702-140059190", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Atomic Energy Commission" } ] }, "doi": "10.1146/annurev.ns.08.120158.001115", "resource_type": "article", "pub_year": "1958", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/a15bt-e2r03", "eprint_id": 46414, "eprint_status": "archive", "datestamp": "2023-08-19 03:11:00", "lastmod": "2023-10-26 19:43:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chupp-E-L", "name": { "family": "Chupp", "given": "E. L." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "J. W. M." } }, { "id": "Mark-H", "name": { "family": "Mark", "given": "Hans" } } ] }, "title": "Measurement of High-Energy Gamma-Rays with a Photographic Bent Crystal Spectrograph", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1958 The American Institute of Physics. \n\nReceived September 12, 1958.\n\nThe authors wish to acknowledge the support of Dr. A.\nJ. Kirschbaum in carrying out this work. \n\nWork done under the auspices of the U. S. Atomic Energy\nCommission.\n\nPublished - 1.1716110.pdf
", "abstract": "It has been shown by one of the authors and his coworkers\nthat it is possible to determine accurately the\nwavelengths of gamma rays with quantum energies up to\n1.3 Mev by direct crystal diffraction methods using the\nMark I 2-meter bent crystal spectrograph at the California\nInstitute of Technology. They were able to record and to\nmeasure with a precision of one part in 10^3 the two gamma\nrays at 1.17 and 1.33 Mev which are emitted by a Co^(60)\nsource.", "date": "1958-12", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "29", "number": "12", "publisher": "American Institute of Physics", "pagerange": "1153-1154", "id_number": "CaltechAUTHORS:20140621-121044295", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-121044295", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Atomic Energy Commission" } ] }, "doi": "10.1063/1.1716110", "primary_object": { "basename": "1.1716110.pdf", "url": "https://authors.library.caltech.edu/records/a15bt-e2r03/files/1.1716110.pdf" }, "resource_type": "article", "pub_year": "1958", "author_list": "Chupp, E. L.; DuMond, J. W. M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/asdg1-wp946", "eprint_id": 80660, "eprint_status": "archive", "datestamp": "2023-08-19 03:11:17", "lastmod": "2023-10-17 17:04:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Present Status of Precise Information on the Universal Physical Constants. Has the Time Arrived for Their Adoption to Replace Our Present Arbitrary Conventional Standards?", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1958 IRE. \n\nManuscript received by the PGI, August 1, 1958.\n\nPublished - 05006783.pdf
", "abstract": "Three years ago Dr. E. R. Cohen and I prepared and published our latest (1955) least-squares adjustment of all the most reliable data then available bearing on the universal constants of physics and chemistry. Since then new data and information have been accumulating so that a year or two from now the time may perhaps be propitious for us to prepare a new adjustment taking the newly-gained knowledge into account. At present it is too early to attempt such a re-evaluation since many of the investigations and re-determinations now under way are still far from completed. I shall be obliged, therefore, to content myself in this talk with a description of the sources of information upon which our 1955 evaluation was based, mentioning however, the weak points where these are now either well established as errors or at least considered to be under strong suspicion of systematic error. I shall also tell you a little of some of the new re-evaluations now under way.", "date": "1958-12", "date_type": "published", "publication": "IRE Transactions on Instrumentation", "volume": "I-7", "number": "3", "publisher": "IRE", "pagerange": "136-175", "id_number": "CaltechAUTHORS:20170821-172631501", "issn": "0096-2260", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170821-172631501", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "collection": "CaltechAUTHORS", "doi": "10.1109/IRE-I.1958.5006783", "primary_object": { "basename": "05006783.pdf", "url": "https://authors.library.caltech.edu/records/asdg1-wp946/files/05006783.pdf" }, "resource_type": "article", "pub_year": "1958", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3rk17-ct451", "eprint_id": 46465, "eprint_status": "archive", "datestamp": "2023-08-19 03:08:33", "lastmod": "2023-10-26 19:46:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cohen-E-R", "name": { "family": "Cohen", "given": "E. Richard" } }, { "id": "Crowe-K-M", "name": { "family": "Crowe", "given": "Kenneth M." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Mendlowitz-H", "name": { "family": "Mendlowitz", "given": "H." } } ] }, "title": "The Fundamental Constants of Physics, Vol. 1 of Interscience Monographs in\n Physics & Astronomy [book review]", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1958 American Institute of Physics.\n\nPublished - 1.3062746.pdf
", "abstract": "Book review of: The Fundamental Constants of Physics. Vol. 1 of\nInterscience Monographs in Physics & Astronomy. By\nE. Richard Cohen, Kenneth M. Crowe, Jesse W. M.\nDuMond. 287 pp. Interscience Publishers, Inc., New\nYork, 1957. \nReviewed by H. Mendlowitz, National\nBureau of Standards.", "date": "1958-09", "date_type": "published", "publication": "Physics Today", "volume": "11", "number": "9", "publisher": "American Institute of Physics", "pagerange": "46-48", "id_number": "CaltechAUTHORS:20140624-100332618", "issn": "0031-9228", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-100332618", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.3062746", "primary_object": { "basename": "1.3062746.pdf", "url": "https://authors.library.caltech.edu/records/3rk17-ct451/files/1.3062746.pdf" }, "resource_type": "article", "pub_year": "1958", "author_list": "Cohen, E. Richard; Crowe, Kenneth M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/5gewe-7ar50", "eprint_id": 2621, "eprint_status": "archive", "datestamp": "2023-08-21 22:41:05", "lastmod": "2023-10-13 23:38:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hatch-E-N", "name": { "family": "Hatch", "given": "E. N." } }, { "id": "Boehm-F", "name": { "family": "Boehm", "given": "F." } }, { "id": "Marmier-P", "name": { "family": "Marmier", "given": "P." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "J. W. M." } } ] }, "title": "Rotational and intrinsic levels in Tm169 and Lu175", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91956 The American Physical Society. \n\nReceived 23 July 1956. \n\nWe wish to thank Dr. Steven A. Moszkowski for many helpful discussions. We also wish to acknowledge the contribution of Mr. H. Henrikson in designing and constructing the low-energy semicircular beta-ray spectrometer.", "abstract": "Nuclear levels in Tm169 excited by electron capture of Yb169, and levels in Lu175 excited by both beta decay of Yb175 and electron capture of Hf175 have been studied by using the curved-crystal gamma-ray spectrometer and the ring-focusing beta-ray spectrometer, as well as a semicircular beta-ray spectrometer for low energies. From the precision energies and the multipolarity determinations, the levels in Tm169 have the following energies in kev, and spin and parity assignments: A (ground state) (\u00bd+), B 8.42 (3/2+), C 118.20 (5/2+), D 138.95 (7/2+), E 316.19 (7/2+), F 379.31 (7/2-), G 472.91 (9/2-). Levels A, B, C, and D are members of a rotational band whose characteristic constants are given. Levels E and F are interpreted as particle excitations and level G as a rotational level based on the state F. The Lu175 excited states have the following energies in kev, spins, and parities: A (ground state) (7/2+), B 113.81 (9/2+), C 251.46 (11/2+), D 343.40 (5/2+), E 396.31 (9/2-), F 432.76 (7/2+), G 504.7 (1/2+). A, B, and C form a rotational band for which the characteristic constants are given. Some features of the levels and transition probabilities are discussed and compared with the unified model. A brief survey of second-order rotational energy constants and of intrinsic excitation levels is given.", "date": "1956-11-01", "date_type": "published", "publication": "Physical Review", "volume": "104", "number": "3", "publisher": "Physical Review", "pagerange": "745-752", "id_number": "CaltechAUTHORS:HATpr56", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:HATpr56", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.104.745", "primary_object": { "basename": "HATpr56.pdf", "url": "https://authors.library.caltech.edu/records/5gewe-7ar50/files/HATpr56.pdf" }, "resource_type": "article", "pub_year": "1956", "author_list": "Hatch, E. N.; Boehm, F.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/qfzr9-x7t81", "eprint_id": 1066, "eprint_status": "archive", "datestamp": "2023-08-21 22:37:42", "lastmod": "2023-10-13 22:06:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Baggerly-L-L", "name": { "family": "Baggerly", "given": "L. L." } }, { "id": "Marmier-P", "name": { "family": "Marmier", "given": "P." } }, { "id": "Boehm-F", "name": { "family": "Boehm", "given": "F." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "J. W. M." } } ] }, "title": "Decay of Ir192", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91955 The American Physical Society \n\nWork supported in part by the U. S. Atomic Energy Commission. We wish to acknowledge the assistance of E. Hatch, S. Raff, and P. Snelgrove in the collection of data, and of F. Humphrey for chemical separations.", "abstract": "A study has been made of the gamma radiation following the decay of Ir192. The energies, intensities, internal conversion coefficients and multipolarities of the gamma transitions have been determined. Energy level schemes for the daughter nuclei, Pt192 and Os192, are proposed. The spins and parities of most of the levels are given.", "date": "1955-12-01", "date_type": "published", "publication": "Physical Review", "volume": "100", "number": "5", "publisher": "Physical Review", "pagerange": "1364-1367", "id_number": "CaltechAUTHORS:BAGpr55", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:BAGpr55", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.100.1364", "primary_object": { "basename": "BAGpr55.pdf", "url": "https://authors.library.caltech.edu/records/qfzr9-x7t81/files/BAGpr55.pdf" }, "resource_type": "article", "pub_year": "1955", "author_list": "Baggerly, L. L.; Marmier, P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/bfgmq-ngr85", "eprint_id": 46415, "eprint_status": "archive", "datestamp": "2023-08-19 02:33:44", "lastmod": "2023-10-26 19:43:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Henke-B-L", "name": { "family": "Henke", "given": "Burton L." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Submicroscopic Structure Determination by Long Wavelength X\u2010Ray Diffraction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1955 American Institute of Physics. \n\nReceived May 3, 1954; revised version received February 14, 1955.\n\n\nThis research was supported by funds from the Office of\nNaval Research and the U. S. Atomic Energy Commission.\n\nThis work\nwas the subject of the thesis of Burton L. Henke for his doctorate\nand is being extended as part of a soft x-ray research program\nat Pomona College under contract with the Office of Scientific\nResearch (U. S. Air Force). \n\nWe would like to acknowledge the invaluable assistance\nof Mr. Herbert Henrikson and Mr. Raymond\nBurt in the design and construction of the total reflection\ncamera, and that of Mr. Theodore Garner in\nthe later modification of this instrument.\n\nPublished - 1.1722117.pdf
", "abstract": "This paper reviews the theory of low angle x\u2010ray diffraction as applied in the long wavelength region for the determination of particle sizes and shapes and other structural features in the submicroscopic size range and emphasizes the advantages to be gained by employing the longer x\u2010ray wavelengths (8 to 25 A). It also is intended to serve as an introduction to a description of an entirely new instrumental technique developed for this long wavelength range utilizing a diffraction apparatus consisting of a special gas\u2010filled x\u2010ray tube and a total reflection camera in which the primary radiation is simultaneously monochromatized and made to converge to a point focus. The sample for study is placed in the converging part of the primary beam and the diffraction patterns are formed around the point focus on a photographic film.", "date": "1955-07", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "26", "number": "7", "publisher": "American Institute of Physics", "pagerange": "903-917", "id_number": "CaltechAUTHORS:20140621-121757299", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-121757299", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)" }, { "agency": "Atomic Energy Commission" } ] }, "doi": "10.1063/1.1722117", "primary_object": { "basename": "1.1722117.pdf", "url": "https://authors.library.caltech.edu/records/bfgmq-ngr85/files/1.1722117.pdf" }, "resource_type": "article", "pub_year": "1955", "author_list": "Henke, Burton L. and DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/mkeqm-7q553", "eprint_id": 1065, "eprint_status": "archive", "datestamp": "2023-08-21 22:35:32", "lastmod": "2023-10-13 22:06:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Murray-J-J", "name": { "family": "Murray", "given": "J. J." } }, { "id": "Boehm-F", "name": { "family": "Boehm", "given": "F." } }, { "id": "Marmier-P", "name": { "family": "Marmier", "given": "P." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "J. W. M." } } ] }, "title": "Decays of Ta182 and Ta183", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91955 The American Physical Society \n\nWork supported by Office of Ordnance Research (U. S. Army), and the U. S. Atomic Energy Commission, and performed in part with equipment built with funds granted by the Research Corporation of America. \n\nA portion of this work was submitted by Joseph J. Murray as a Ph.D. thesis, California Institute of Technology, 1954 (unpublished). \n\nWe gratefully acknowledge the efforts of Dr. W. B. Lewis in arranging for irradiations in the Materials Testing Reactor, Arco, Idaho, under the auspices of the Phillips Petroleum Company. \n\nWe wish to acknowledge the vaulable contribution of Mr. P. Snelgrove. Also we wish to thank Professor A. Bohr for many helpful discussions.", "abstract": "The beta - decays of Ta182 and Ta183 into excited states of W182 and W183 have been studied using a curved crystal gamma-ray diffraction spectrometer and a homogeneous field, ring focusing beta-ray spectrometer. In each case de-excitation of the daughter nucleus gives rise to complex gamma-ray and conversion electron spectra. Energies and relative intensities of gamma rays and conversion lines arising from 27 transitions in W182 and 29 transitions in W183 are presented. Internal conversion coefficients and multipolarities have been deduced for most of the transitions and together with the gamma-ray energies form the basis of decay schemes proposed for both W182 and W183. The two decays are reported together because of the close experimental relationship which existed between them as a consequence of the method used for their production, namely, simultaneous production of Ta182 by single neutron capture and Ta183 by double neutron capture from stable Ta181. A corollary result is the value 1.3 x 10^4 barns for the thermal neutron cross section of Ta182.\n\nAn interpretation of these results on W182 in terms of collective rotational motion has been given by A. Bohr and collaborators [Kgl. Danske Videnscab. Selskab, Mat.-fys. Medd. 29, No. 9 (1955)].", "date": "1955-02-15", "date_type": "published", "publication": "Physical Review", "volume": "97", "number": "4", "publisher": "Physical Review", "pagerange": "1007-1016", "id_number": "CaltechAUTHORS:MURpr55", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:MURpr55", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.97.1007", "primary_object": { "basename": "MURpr55.pdf", "url": "https://authors.library.caltech.edu/records/mkeqm-7q553/files/MURpr55.pdf" }, "resource_type": "article", "pub_year": "1955", "author_list": "Murray, J. J.; Boehm, F.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/n5gbe-yf567", "eprint_id": 46417, "eprint_status": "archive", "datestamp": "2023-08-19 02:27:41", "lastmod": "2023-10-26 19:44:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Berreman-D-W", "name": { "family": "Berreman", "given": "Dwight W." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Marmier-P-E", "name": { "family": "Marmier", "given": "Pierre E." } } ] }, "title": "New Point-Focusing Monochromator", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1954 The American Institute of Physics. \n\nReceived August 30, 1954.\n\n\nWork supported by contract with the Office of Naval Research.\n\nPublished - 1.1770990.pdf
", "abstract": "A method is described here for cutting and bending a single\ncrystal for a point-focusing monochromator which does not\nproduce a nondevelopable surface.", "date": "1954-12", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "25", "number": "12", "publisher": "American Institute of Physics", "pagerange": "1219-1220", "id_number": "CaltechAUTHORS:20140621-162436551", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-162436551", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)" } ] }, "doi": "10.1063/1.1770990", "primary_object": { "basename": "1.1770990.pdf", "url": "https://authors.library.caltech.edu/records/n5gbe-yf567/files/1.1770990.pdf" }, "resource_type": "article", "pub_year": "1954", "author_list": "Berreman, Dwight W.; DuMond, Jesse W. M.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1q3z0-c3t48", "eprint_id": 1063, "eprint_status": "archive", "datestamp": "2023-08-21 22:34:19", "lastmod": "2023-10-13 22:06:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Boehm-F", "name": { "family": "Boehm", "given": "F." } }, { "id": "Marmier-P", "name": { "family": "Marmier", "given": "P." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "J. W. M." } } ] }, "title": "Gamma Transitions in W182", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91954 The American Physical Society \n\nDuring the preparation of the manuscript, a paper on the same subject by C. M. Fowler et al., appeared in Phys. Rev. 94, 1082 (1954), showing close agreement with the present results. \n\nAssisted by contracts with the U. S. Atomic Energy Commission and the Office of Ordnance Research.", "abstract": "[No abstract].", "date": "1954-08-01", "date_type": "published", "publication": "Physical Review", "volume": "95", "number": "3", "publisher": "Physical Review", "pagerange": "864-865", "id_number": "CaltechAUTHORS:BOEpr54b", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:BOEpr54b", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.95.864", "primary_object": { "basename": "BOEpr54b.pdf", "url": "https://authors.library.caltech.edu/records/1q3z0-c3t48/files/BOEpr54b.pdf" }, "resource_type": "article", "pub_year": "1954", "author_list": "Boehm, F.; Marmier, P.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/4ndfh-xwh73", "eprint_id": 46419, "eprint_status": "archive", "datestamp": "2023-08-19 02:11:58", "lastmod": "2023-10-26 19:44:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "An Introduction to Scientific Research [Book Review]", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1953 American Association of Physics Teachers.\n\nPublished - 1.1933468.pdf
", "abstract": "Book review of: An Introduction to Scientific Research. E. BRIGHT WILSON,\nJR. Pp. 375+xiii, Figs. 53, McGraw-Hill\nBook Company, Inc., New York, 1952.", "date": "1953-05", "date_type": "published", "publication": "American Journal of Physics", "volume": "21", "number": "5", "publisher": "American Association of Physics Teachers", "pagerange": "392-394", "id_number": "CaltechAUTHORS:20140621-163604939", "issn": "0002-9505", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-163604939", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1119/1.1933468", "primary_object": { "basename": "1.1933468.pdf", "url": "https://authors.library.caltech.edu/records/4ndfh-xwh73/files/1.1933468.pdf" }, "resource_type": "article", "pub_year": "1953", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/2x798-adj18", "eprint_id": 46421, "eprint_status": "archive", "datestamp": "2023-08-19 02:06:10", "lastmod": "2023-10-26 19:44:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Improvements in the precision of beta-ray spectroscopy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1952 American Institute of Physics. \n\nThis is the second of two articles\nbased on an invited paper presented before the American Physical\nSociety last May. The first, under the title Higher Precision in\nNuclear Spectroscopy, appeared on page 13 of last month's issue.\n\nPublished - 1.3067417.pdf
", "abstract": "The direct measurement of gamma\u2010rays only yields about half the picture in the study of nuclear energy levels. The other, and indeed to most physicists more familiar, half concerns the \u03b2\u2010rays, including in this term both the continuous \u03b2\u2010ray spectrum and the line spectrum by \"conversion\", either internal or external. Ever since 1948, therefore, we have been much occupied with the design and construction along rather novel lines of a high precision helical focusing magnetic \u03b2\u2010ray spectrometer planned as a companion instrument to the crystal diffraction spectrometer as regards absolute precision and accuracy. We have only very recently completed this instrument and made the first tests on it which indicate that it will meet all our expectations both as to high absolute accuracy and high luminosity and sensitivity to weak sources.\n\nThe beta\u2010ray spectrometer discussed in the following pages has recently been completed at the California Institute of Technology. It is shown in cross section on the cover.", "date": "1952-12", "date_type": "published", "publication": "Physics Today", "volume": "5", "number": "12", "publisher": "American Institute of Physics", "pagerange": "10-13", "id_number": "CaltechAUTHORS:20140621-164718597", "issn": "0031-9228", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-164718597", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.3067417", "primary_object": { "basename": "1.3067417.pdf", "url": "https://authors.library.caltech.edu/records/2x798-adj18/files/1.3067417.pdf" }, "resource_type": "article", "pub_year": "1952", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/dx5xy-p1g23", "eprint_id": 46420, "eprint_status": "archive", "datestamp": "2023-08-19 02:05:27", "lastmod": "2023-10-26 19:44:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Higher precision in nuclear spectroscopy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1952 American Institute of Physics.\n\nPublished - 1.3067390.pdf
", "abstract": "For nearly six years there has been in existence\nat the California Institute of Technology a\nprogram of research work directed at increasing the\nprecision of all measurements in nuclear spectroscopy\nand especially the precision with which nuclear energy\nlevels may be determined. This trend toward higher\nprecision of measurement is to be observed at present\nin nearly every area of nuclear physics (except possibly\nin the still new very high energy field) for it is\ngenerally realized that, while much primary qualitative\ninformation has been acquired, a real understanding and\ninterpretation of the problems of nuclear structure and\nthe internal mechanics of nuclei must wait for a sufficient\nfund of accurate and reliable quantitative numerical\ndata to furnish a foundation for theory to\nbuild upon.", "date": "1952-11", "date_type": "published", "publication": "Physics Today", "volume": "5", "number": "11", "publisher": "American Institute of Physics", "pagerange": "13-20", "id_number": "CaltechAUTHORS:20140621-164025966", "issn": "0031-9228", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-164025966", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "collection": "CaltechAUTHORS", "doi": "10.1063/1.3067390", "primary_object": { "basename": "1.3067390.pdf", "url": "https://authors.library.caltech.edu/records/dx5xy-p1g23/files/1.3067390.pdf" }, "resource_type": "article", "pub_year": "1952", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ajd6g-b5n65", "eprint_id": 46412, "eprint_status": "archive", "datestamp": "2023-08-19 02:03:07", "lastmod": "2023-10-26 19:43:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shenfil-L", "name": { "family": "Shenfil", "given": "Leon" } }, { "id": "Danielson-W-E", "name": { "family": "Danielson", "given": "Warren E." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "A Point Focusing X-Ray Monochromator for the Study of Low Angle Diffraction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1952 The American Institute of Physics. \n\n(Received February 18, 1952) \n\nThis work was performed and financed under the joint\nsponsorship of the ONR and the AEC by contract with the\nCalifornia Institute of Technology. \n\nIn conclusion we wish to express our gratitude to\nthe ONR for their generous support and sponsorship\nof the development of this instrument and to Professor\nLinus Pauling of this Institute for his faith in and\nsupport of the project in recommending it to its present\nsponsors when its success was still problematical. We\nare also most grateful for the friendly advice and cooperation\nof Professor R. B. Corey of the C.LT. Chemistry\nDepartment and to Professors J. Weigle and G. W.\nBeadle of the C.I.T. Biology Department for most\nhelpful advice and discussions regarding possible\nproblems suitable for the new instrument.\n\nPublished - 1.1702319.pdf
", "abstract": "A point focusing x\u2010ray monochromator was designed and constructed for low angle scattering studies. The anastigmatic point focus is achieved by means of two cylindrically bent quartz crystals whose focal circles are mutually perpendicular. The beam, emanating from the copper target of an x\u2010ray tube, is reflected in succession, first from the crystal defining the horizontal focal circle, and second from the crystal defining the vertical focal circle following which it comes to a monochromatic point focus of wavelength 1.537A (CuK\u03b1_1). The sample to be studied is placed between the second crystal and the point focus, and the scattered beam is detected by means of a photographic film placed at the point focus, at right angles to the undeviated beam, the latter being suppressed by means of an absorber, or allowed to pass through a hole in the film.\n\nMathematical analysis, in which a ray was traced through the two\u2010crystal system, revealed correctly the shape and size of the point focus, and the possibility of reducing the latter in size by stopping down the beam emerging from the target.", "date": "1952-08", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "23", "number": "8", "publisher": "American Institute of Physics", "pagerange": "854-859", "id_number": "CaltechAUTHORS:20140621-115706810", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-115706810", "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" } ] }, "collection": "CaltechAUTHORS", "doi": "10.1063/1.1702319", "primary_object": { "basename": "1.1702319.pdf", "url": "https://authors.library.caltech.edu/records/ajd6g-b5n65/files/1.1702319.pdf" }, "resource_type": "article", "pub_year": "1952", "author_list": "Shenfil, Leon; Danielson, Warren E.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ktxq0-80r35", "eprint_id": 46413, "eprint_status": "archive", "datestamp": "2023-08-19 02:03:12", "lastmod": "2023-10-26 19:43:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Danielson-W-E", "name": { "family": "Danielson", "given": "Warren E." } }, { "id": "Shenfil-L", "name": { "family": "Shenfil", "given": "Leon" } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Latex Particle Size Determination Using Diffraction Peaks Obtained with the Point Focusing X-Ray Monochromator", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1952 The American Institute of Physics. \n\nReceived February 18, 1952.\n\nThis work was performed and financed under the joint sponsorship\nof the ONR and AEC by contract with the California\nInstitute of Technology. \n\nWe take this opportunity to express our gratitude\nto the sponsors of this research (the ONR and the\nAEC) for their generous support and our deep appreciation\nto Professor Linus Pauling of this Institute, who\nrecommended its support and encouragement to our\nsponsors when its success was still uncertain. We are\nalso happy to have this opportunity to thank Professor\nR. B. Corey of the C.I.T. Chemistry Department and\nProfessors J. Weigle and G. W. Beadle of the C.l.T.\nBiology Department for most helpful advice and\ndiscussions regarding future problems suitable for\nthe new instrument.\n\nPublished - 1.1702320.pdf
", "abstract": "We describe the results of experiments we have made, using the point focusing monochromator as the primary tool, to determine the particle size of latex spheres. The suitability of the instrument for this particular study is described and the experimental data obtained are tabulated, these data coming from our experiments with three physically distinct samples of Dow latex. We attempt to make a critical interpretation of the data by considering separately several possible space arrangements which the latex spheres might assume when the water, which is initially the suspending fluid, is evaporated. Corrections for the finite size and shape of the \"point\" focus are described. The absence of a significant difference in the mean particle sizes of the three samples considered is established. \n\nThe data from all three samples is combined to yield a mean particle diameter under an external pressure of one atmosphere of 2687.5A with a statistical standard deviation of 1.2A and a fixed (systematic) error estimated to be not more than \u00b17A.", "date": "1952-08", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "23", "number": "8", "publisher": "American Institute of Physics", "pagerange": "860-865", "id_number": "CaltechAUTHORS:20140621-120410463", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-120410463", "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": "10.1063/1.1702320", "primary_object": { "basename": "1.1702320.pdf", "url": "https://authors.library.caltech.edu/records/ktxq0-80r35/files/1.1702320.pdf" }, "resource_type": "article", "pub_year": "1952", "author_list": "Danielson, Warren E.; Shenfil, Leon; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9rf0h-kc423", "eprint_id": 3794, "eprint_status": "archive", "datestamp": "2023-08-21 22:22:33", "lastmod": "2023-10-16 16:09:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Cohen-E-R", "name": { "family": "Cohen", "given": "E. Richard" } } ] }, "title": "Least-squares adjusted values of the atomic constants as of December, 1950", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91951 The American Physical Society. \n\nReceived 8 March 1951.", "abstract": "As part of the work of the National Research Council Committee on Constants and Conversion Factors of Physics and at the request of its chairman, E. U. Condon, we have prepared a report,(1) dated December, 1950, giving a complete re-evaluation of the atomic constants in the light of the wealth of important new and very accurate data obtained since our previous study of January, 1948.", "date": "1951-05-15", "date_type": "published", "publication": "Physical Review", "volume": "82", "number": "4", "publisher": "Physical Review", "pagerange": "555-556", "id_number": "CaltechAUTHORS:DUMpr51", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr51", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.82.555.3", "primary_object": { "basename": "DUMpr51.pdf", "url": "https://authors.library.caltech.edu/records/9rf0h-kc423/files/DUMpr51.pdf" }, "resource_type": "article", "pub_year": "1951", "author_list": "DuMond, Jesse W. M. and Cohen, E. Richard" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ffdqx-2n132", "eprint_id": 46418, "eprint_status": "archive", "datestamp": "2023-08-19 01:38:55", "lastmod": "2023-10-26 19:44:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Crystals and X-Rays [Book Review]", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1950 American Association of Physics Teachers.\n\nPublished - 1.1932583.pdf
", "abstract": "Book review of: Crystals and X-Rays. KATHLEEN LONSDALE. Pp. 199, D. Van Nostrand Company, Inc., New\nYork, 1949.", "date": "1950-05", "date_type": "published", "publication": "American Journal of Physics", "volume": "18", "number": "5", "publisher": "American Association of Physics Teachers", "pagerange": "325-327", "id_number": "CaltechAUTHORS:20140621-163056209", "issn": "0002-9505", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-163056209", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1119/1.1932583", "primary_object": { "basename": "1.1932583.pdf", "url": "https://authors.library.caltech.edu/records/ffdqx-2n132/files/1.1932583.pdf" }, "resource_type": "article", "pub_year": "1950", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/yqxt4-jjy13", "eprint_id": 46416, "eprint_status": "archive", "datestamp": "2023-08-19 01:37:39", "lastmod": "2023-10-26 19:43:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Point-Focus X-Ray Monochromators for Low Angle Diffraction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1950 American Institute of Physics. \n\nSubmitted November 21, 1949.\n\nPublished - 1.1745527.pdf
", "abstract": "Guinier has applied the principle of the reflection type\ncurved crystal focusing x-ray monochromator to improve\nboth intensity and angular resolution in low angle x-ray diffraction\nstudies. In Guinier's method, a thin sample is placed in the\nconvergent monochromatic x-ray beam and the low angle diffraction pattern is formed as a diffuse distribution symmetrically\ndisposed on either side of the central primary line focused by the\ncrystal.", "date": "1950-02", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "21", "number": "2", "publisher": "American Institute of Physics", "pagerange": "188-189", "id_number": "CaltechAUTHORS:20140621-161721666", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-161721666", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.1745527", "primary_object": { "basename": "1.1745527.pdf", "url": "https://authors.library.caltech.edu/records/yqxt4-jjy13/files/1.1745527.pdf" }, "resource_type": "article", "pub_year": "1950", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/rmj66-12s66", "eprint_id": 5113, "eprint_status": "archive", "datestamp": "2023-08-21 22:17:03", "lastmod": "2023-10-16 18:07:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lind-D-A", "name": { "family": "Lind", "given": "David A." } }, { "id": "Brown-J-R", "name": { "family": "Brown", "given": "J. R." } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Precision wave-length measurements of the 1.1- and 1.3-Mev lines of CO60 with the two-meter focusing curved-crystal spectrometer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91949 The American Physical Society. \n\nReceived 15 August 1949.", "abstract": "Recent improvements in the two-meter focusing curved-crystal gamma-ray spectrometer are described which have extended its quantum energy range well above 1 Mev and have also yielded much better luminosity and resolving power than were obtained initially. The improved components are (1) the crystal holder whose aperture and resolving power have been nearly doubled and (2) the collimator the new model of which can now discriminate between the reflected and transmitted beams when these differ in direction by only 8 minutes of arc, a threefold improvement over our first model. Our plans for further possible improvements and the factors governing these are also discussed. Wavelengths of two gamma-rays emitted following \u03b2-decay of Co60 have been measured with this new equipment using a source of about 50 mc strength and found to have values of (9.308\u00b10.005)\u00d710-11 cm and (10.580\u00b10.005)\u00d710-11 cm corresponding to quantum energies of 1.3316\u00b10.0010 Mev and 1.1715\u00b10.0010 Mev, respectively. The lines appear to have equal intensities. The integrated reflection coefficient of the (310) planes of the curved-quartz crystal still appears to follow a \u03bb2-dependence on wave-length down to 9 x.u. the shortest so far observed.", "date": "1949-12-15", "date_type": "published", "publication": "Physical Review", "volume": "76", "number": "12", "publisher": "Physical Review", "pagerange": "1838-1843", "id_number": "CaltechAUTHORS:LINpr49", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:LINpr49", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.76.1838", "primary_object": { "basename": "LINpr49.pdf", "url": "https://authors.library.caltech.edu/records/rmj66-12s66/files/LINpr49.pdf" }, "resource_type": "article", "pub_year": "1949", "author_list": "Lind, David A.; Brown, J. R.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/jn497-yay24", "eprint_id": 46469, "eprint_status": "archive", "datestamp": "2023-08-19 01:28:27", "lastmod": "2023-10-26 19:46:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Conditions for Optimum Luminosity and Energy Resolution in an Axial \u03b2\u2010Ray Spectrometer with Homogeneous Magnetic Field", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1949 American Institute of Physics.\n\nReceived October 18, 1948.\n\nThe author wishes to acknowledge with gratitude\nvery helpful criticisms and discussions of this paper\nby E. R. Cohen and by Professor R. F. Christy.\n\nPublished - 1.1741480.pdf
Erratum - 1.1741628.pdf
", "abstract": "In a \u03b2\u2010ray spectrometer with axial homogeneous magnetic field, it is shown that optimum energy resolution and luminosity are obtained when the trajectories make an angle close to 45\u00b0 with the field and that an annular resolving slit should be provided at a determined radial and axial location relative to the source. The combined effect of three independent sources of instrumental energy line width is analyzed for the optimum condition. Formulas are given for the optimum dimensions, the energy resolution and the luminosity.", "date": "1949-03", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "20", "number": "3", "publisher": "American Institute of Physics", "pagerange": "160-169", "id_number": "CaltechAUTHORS:20140624-105800234", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-105800234", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.1741480", "primary_object": { "basename": "1.1741480.pdf", "url": "https://authors.library.caltech.edu/records/jn497-yay24/files/1.1741480.pdf" }, "related_objects": [ { "basename": "1.1741628.pdf", "url": "https://authors.library.caltech.edu/records/jn497-yay24/files/1.1741628.pdf" } ], "resource_type": "article", "pub_year": "1949", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9rnr4-vph25", "eprint_id": 5535, "eprint_status": "archive", "datestamp": "2023-08-21 22:09:16", "lastmod": "2023-10-16 19:16:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Lind-D-A", "name": { "family": "Lind", "given": "David A." } }, { "id": "Watson-B-B", "name": { "family": "Watson", "given": "Bernard B." } } ] }, "title": "Precision wave-length and energy measurement of gamma-rays from Au198 with a focusing quartz crystal spectrometer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91948 The American Physical Society. \n\nReceived 29 March 1948. \n\nWork supportedc since March 1947 by contract with the Office of Naval Research.", "abstract": "A recent paper(1) describes a precision focusing curved crystal x-ray and gamma-ray spectrometer (2-meter focal length) constructed at the California Institute of Technology. This instrument has now been used to study the 0.41-Mev gamma-ray line from a 1-curie source of the artificial radioactive isotope of gold, Au198, of half-life 2.7 days.", "date": "1948-06-01", "date_type": "published", "publication": "Physical Review", "volume": "73", "number": "11", "publisher": "Physical Review", "pagerange": "1392-1394", "id_number": "CaltechAUTHORS:DUMpr48", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr48", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.73.1392", "primary_object": { "basename": "DUMpr48.pdf", "url": "https://authors.library.caltech.edu/records/9rnr4-vph25/files/DUMpr48.pdf" }, "resource_type": "article", "pub_year": "1948", "author_list": "DuMond, Jesse W. M.; Lind, David A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/vn5aa-kwd91", "eprint_id": 47758, "eprint_status": "archive", "datestamp": "2023-08-19 01:20:34", "lastmod": "2023-10-20 23:27:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Cohen-E-R", "name": { "family": "Cohen", "given": "E. Richard" } } ] }, "title": "Our Knowledge of the Atomic Constants F, N, m, and h in 1947, and of Other Constants Derivable Therefrom", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1948 The American Physical Society. \n\n\nThe authors are much indebted to Professor R. T. Birge for pointing out the oversight, in their original manuscript, of his improved results regarding Avogadro's number which are published in his 1945 paper. The numerical values in the present paper have been revised to accord with this result. \n\nThe authors are deeply indebted to Dr. Birge for help and criticism over a long period. They have relied extensively on his published work and his generous extensive private communications.\n\nPublished - RevModPhys.20.82.pdf
Erratum - DUMrmp49.pdf
", "abstract": "The present paper aims to deal only with a\nlimited portion of the subject, the evaluation of\nthe so-called atomic constants: e the electronic\ncharge, m the electronic mass, and h Planck's\nconstant of action together with certain auxiliary\nconstants intimately associated with them. A\nnumber of useful physical constants which can\nbe computed from the above data will also be\nevaluated.", "date": "1948-01", "date_type": "published", "publication": "Reviews of Modern Physics", "volume": "20", "number": "1", "publisher": "American Physical Society", "pagerange": "82-108", "id_number": "CaltechAUTHORS:20140731-184306534", "issn": "0034-6861", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140731-184306534", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/RevModPhys.20.82", "primary_object": { "basename": "DUMrmp49.pdf", "url": "https://authors.library.caltech.edu/records/vn5aa-kwd91/files/DUMrmp49.pdf" }, "related_objects": [ { "basename": "RevModPhys.20.82.pdf", "url": "https://authors.library.caltech.edu/records/vn5aa-kwd91/files/RevModPhys.20.82.pdf" } ], "resource_type": "article", "pub_year": "1948", "author_list": "DuMond, Jesse W. M. and Cohen, E. Richard" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/emvx0-dzx35", "eprint_id": 46468, "eprint_status": "archive", "datestamp": "2023-08-19 01:18:18", "lastmod": "2023-10-26 19:46:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "A High Resolving Power, Curved\u2010Crystal Focusing Spectrometer for Short Wave\u2010Length X-Rays and Gamma\u2010Rays", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1947 American Institute of Physics.\n\nReceived May 21, 1947.\n\nThis research is now being conducted under Navy\nContract N6onr-244 Task Order IV, dated March 1, 1947.\n\nThe author wishes gratefully to acknowledge\nthe most valuable assistance of J. P. Youtz, W.\nK. H. Panofsky, Russel Yost, David Lind, and\nE. R. Cohen in the work of assembly and testing\nof this instrument. The construction of the parts\nwas accomplished by B. E. Merkel, instrument\nmaker of the California Institute of Technology\nPhysics Department instrument shop, with\nadmirable skill which deserves the writer's\nhighest praise.\n\nPublished - 1.1741017.pdf
", "abstract": "Description is given of a transmission\u2010type, curved\u2010crystal focusing spectrometer for short wave\u2010length x\u2010rays, and gamma\u2010rays having a dispersion of 1.186 x.u. per mm at short wave\u2010lengths. The spectrometer utilizes the (310) planes of quartz in a crystalline plate of dimensions 80\u00d770\u00d71.0 mm curved cylindrically to a radius of two meters. High luminosity is obtained since the useful aperture in the crystal holder has an area of 10 cm2 and subtends 0.00025 stereradians at the focus. It also affords high resolution since by photographic tests with x\u2010rays the curved plate has been shown to focus a specified x\u2010ray wave\u2010length to within 0.06 mm of the same position on the focal circle for all parts of its useful aperture and over the entire operating wave\u2010length range. The geometry of the mechanism permits absolute measurements with a precision screw of the sine of the Bragg angle on both sides of the reflecting planes, affording a wave\u2010length range which includes at longest wave\u2010lengths the K\u2010spectrum of silver and goes down to zero wave\u2010lengths. For short wave\u2010length gamma\u2010rays the source is placed at the focus. A multiple\u2010slit collimator of tapering die\u2010cast lead partitions spaced apart with tapering separators, is used at short wave\u2010lengths to transmit the monochromatic diffracted beam and absorb the directly transmitted and scattered heterogeneous beam. The present collimator limits the spectrum that can be studied to a shortest wave\u2010length of 7. x.u. corresponding to 1.75 Mev. The intensity of the diffracted beam is to be measured with a special multi\u2010cellular G. M. counting tube of high efficiency, provided with a number of thin lead partitions through which the beam passes successively. In photographic spectra made with this instrument the tungsten and also the silverK\u03b2_1\u03b2_3 doublet is completely and clearly resolved. Reproductions of such photographic x\u2010ray spectra are shown in which the line breadths have substantially the natural breadth. Fluorescence spectra of silver have been made in 10\u2010minute exposures. A companion paper gives the all\u2010important precision technique of generating the curved cylindrical stainless steel clamping blocks for the crystal.", "date": "1947-09", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "18", "number": "9", "publisher": "American Institute of Physics", "pagerange": "626-638", "id_number": "CaltechAUTHORS:20140624-103455929", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-103455929", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N6onr-24430" } ] }, "collection": "CaltechAUTHORS", "doi": "10.1063/1.1741017", "primary_object": { "basename": "1.1741017.pdf", "url": "https://authors.library.caltech.edu/records/emvx0-dzx35/files/1.1741017.pdf" }, "resource_type": "article", "pub_year": "1947", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/0b390-kpt96", "eprint_id": 46466, "eprint_status": "archive", "datestamp": "2023-08-19 01:18:13", "lastmod": "2023-10-26 19:46:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Lind-D-A", "name": { "family": "Lind", "given": "David A." } }, { "id": "Cohen-E-R", "name": { "family": "Cohen", "given": "E. Richard" } } ] }, "title": "A Precision Method of Generating Circular Cylindrical Surfaces of Large Radius of Curvature for Use in the Curved-Crystal Spectrometer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1947 American Institute of Physics.\n\nReceived October 9, 1946.\n\nThis research is now being conducted under Navy Contract\nN6onr-244 Task Order IV, dated March 1, 1947.\n\nPublished - 1.1741016.pdf
", "abstract": "A method is here described for generating circular cylindrical surfaces of large radius of curvature on blocks of steel or other material with a close approach to optical precision utilizing an ordinary machine shop surface grinder. Convex and concave surfaces about 3\u00d75 inches in dimensions with radii of curvature of 79 inches (two meters) have been ground by this method both on cast iron and on stainless\u2010steel blocks with a precision of about 0.0002 inches as regards surface imperfections. A very moderate amount of subsequent lapping sufficed to give surfaces of optical precision. The surfaces are used for clamping lamina of crystalline quartz for use in a curved crystal focusing gamma ray spectrometer. A companion paper describes the gamma ray spectrometer.", "date": "1947-09", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "18", "number": "9", "publisher": "American Institute of Physics", "pagerange": "617-626", "id_number": "CaltechAUTHORS:20140624-101434316", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-101434316", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N6onr-244" } ] }, "collection": "CaltechAUTHORS", "doi": "10.1063/1.1741016", "primary_object": { "basename": "1.1741016.pdf", "url": "https://authors.library.caltech.edu/records/0b390-kpt96/files/1.1741016.pdf" }, "resource_type": "article", "pub_year": "1947", "author_list": "DuMond, Jesse W. M.; Lind, David A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/a7c3y-he573", "eprint_id": 46470, "eprint_status": "archive", "datestamp": "2023-08-19 01:13:05", "lastmod": "2023-10-26 19:46:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Cohen-E-R", "name": { "family": "Cohen", "given": "E. Richard" } }, { "id": "Panofsky-W-K-H", "name": { "family": "Panofsky", "given": "W. K. H." } }, { "id": "Deeds-E", "name": { "family": "Deeds", "given": "Edward" } } ] }, "title": "A Determination of the Wave Forms and Laws of Propagation and Dissipation of Ballistic Shock Waves", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1946 Acoustical Society of America.\n\nReceived 27 September 1945.\n\nThis paper is based on work done for the Office of\nScientific Research and Development under Contract No.\nOEMsr-600 with the California Institute of Technology\n\nPublished - 1.1916347.pdf
", "abstract": "Experiments to ascertain the wave forms and laws of propagation and dissipation of ballistic shock waves to large distances (80 yards) from the bullet trajectory are described. Calibers 0.30, 0.50, 20 mm, and 40 mm were studied. In every case an N\u2010shaped wave profile was observed consisting of a sudden rise in pressure, the \"head discontinuity,\" followed by an approximately linear decline to a pressure about equally far below atmospheric and then a second sudden return, the \"tail discontinuity,\" to atmospheric pressure. The peak amplitudes of this disturbance are found to diminish about as the inverse 3/4 power of the miss\u2010distance (perpendicular distance from the trajectory) while the period T\u2032 (measured between the discontinuous fronts) increases about as the 1/4 power of the miss\u2010distance for calibers 0.30, 0.50, and 20 mm. For 40\u2010mm shells the amplitude decays a little faster, about as the inverse 0.9 power of miss\u2010distance over the range studied. A theory taking account of the dissipation of the N\u2010wave energy into heat is developed to explain the observed behavior. A method of measuring absolute N\u2010wave amplitudes by observing the rate of change of period T\u2032 with propagation is described. The theory leads to an absolute relationship at large distances between distance, amplitude, and period in which no arbitrary constants appear.", "date": "1946-07", "date_type": "published", "publication": "Journal of the Acoustical Society of America", "volume": "18", "number": "1", "publisher": "Acoustical Society of America", "pagerange": "97-118", "id_number": "CaltechAUTHORS:20140624-111542495", "issn": "0001-4966", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-111542495", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Scientific Research and Development", "grant_number": "OEMsr-600" } ] }, "collection": "CaltechAUTHORS", "doi": "10.1121/1.1916347", "primary_object": { "basename": "1.1916347.pdf", "url": "https://authors.library.caltech.edu/records/a7c3y-he573/files/1.1916347.pdf" }, "resource_type": "article", "pub_year": "1946", "author_list": "DuMond, Jesse W. M.; Cohen, E. Richard; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/9yz1d-v7v55", "eprint_id": 46472, "eprint_status": "archive", "datestamp": "2023-08-19 00:51:26", "lastmod": "2023-10-26 19:46:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Construction of Thermodynamic Models for Elementary Teaching", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1941 American Association of Physics Teachers.\n\nPublished - 1.1991687.pdf
", "abstract": "The author has found great value in the use\nof solid models in freshman physics teaching\nto illustrate (1) the law of ideal gases, and\n(2) the van der Waals equation of state and the\nbehaviors of vapors and liquids. Many freshman\nstudents have difficulty in visualizing the shape\nof the thermodynamic surfaces from, let us say,\na blackboard sketch of a set of isotherms, and\nthe better part of a precious lecture hour may\nbe consumed in explaining, with many words,\nwhat would be almost obvious if one had a solid\nmodel in his hands. The author has found that\nmore than half of a class of average intelligence,\nhaving learned that an ideal gas is described\nby the equation PV=NRT, will be sorely\npuzzled by the adiabatic equation for ideal gases,\nPV\u03b3=const. It helps these puzzled students surprisingly\nlittle to be told that, since the first\nequation contains three variables, it is not inconsistent\nwith the second. With many of them,\nhowever, the matter becomes clear when they\nare shown an ideal gas surface on which have\nbeen plotted isotherms, adiabatics, and so forth.", "date": "1941-08", "date_type": "published", "publication": "American Journal of Physics", "volume": "9", "number": "4", "publisher": "American Association of Physics Teachers", "pagerange": "234-237", "id_number": "CaltechAUTHORS:20140624-125116421", "issn": "0002-9505", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-125116421", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "collection": "CaltechAUTHORS", "doi": "10.1119/1.1991687", "primary_object": { "basename": "1.1991687.pdf", "url": "https://authors.library.caltech.edu/records/9yz1d-v7v55/files/1.1991687.pdf" }, "resource_type": "article", "pub_year": "1941", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/kc2h7-08v33", "eprint_id": 46422, "eprint_status": "archive", "datestamp": "2023-08-19 00:45:57", "lastmod": "2023-10-26 19:44:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse" } }, { "id": "Youtz-J-P", "name": { "family": "Youtz", "given": "J. Paul" } } ] }, "title": "An X-Ray Method of Determining Rates of Diffusion in the Solid State", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1940 The American Institute of Physics. \n\nReceived November 7, 1939. \n\nWe wish gratefully to acknowledge our indebtedness\nto Dr. Leon L. Watters of New York\nCity for the funds which have supported this\nwork.\n\nPublished - 1.1712784.pdf
", "abstract": "Gold and copper were simultaneously deposited in vacuum by vaporization on a plate of glass, the copper being deposited at a uniform rate while the gold was deposited in one hundred stratified layers in the copper by alternately raising and lowering the temperature of the molybdenum vaporizing trough containing the boiling gold. The translucent deposit so formed had a total thickness of about 10,000A and hence an average interplanar distance of 100A. In an especially constructed constructed x-ray spectrograph selective diffraction of Mo K radiation from these stratified films was observed corresponding to the artificially imposed periodicity of the stratification and the intensity of this diffracted image relative to the direct beam was found to fall off with time so as to indicate a \"half-life\" for the stratified structure of about two days. This suggests a general method for the study of average rates of diffusion and the determination of diffusion coefficients of solids in solids by utilizing the decay of such stratified films. Simple theoretical considerations should, through the action of diffusion alone, rapidly and automatically lose the higher Fourier harmonics of its periodic density distribution function and retain the fundamental in such a way as to render the determination of the diffusion coefficient quite accurate. The observed behavior of the diffracted maxima seem to support these expectations as does also the absence of any intensity in higher orders than the first. This purification by diffusion probably takes place principally during the depositing process itself while the temperatures are still quite high. Formulae are derived relating the observed rate of decay of the diffracted intensity, the artificial \"grating coefficient\" of the strata, and the diffusion coefficient. The method seems especially promising for substances and temperatures where diffusion is so slow as to be otherwise quite unobservable because the diffusion time varies as the square of the distance over which atoms must migrate and in this method these distances are so many orders of magnitude smaller than in any other.", "date": "1940-05", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "11", "number": "5", "publisher": "American Institute of Physics", "pagerange": "357-365", "id_number": "CaltechAUTHORS:20140621-165917384", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140621-165917384", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Leon L. Watters" } ] }, "collection": "CaltechAUTHORS", "doi": "10.1063/1.1712784", "primary_object": { "basename": "1.1712784.pdf", "url": "https://authors.library.caltech.edu/records/kc2h7-08v33/files/1.1712784.pdf" }, "resource_type": "article", "pub_year": "1940", "author_list": "DuMond, Jesse and Youtz, J. Paul" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/063z4-etr67", "eprint_id": 46457, "eprint_status": "archive", "datestamp": "2023-08-19 00:39:55", "lastmod": "2023-10-26 19:45:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "An Approximate Method of Cutting Short Circular Cylindrical Arcs with Very Large Radii of Curvature in the Milling Machine", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1938 American Institute of Physics.\n\nReceived Aug. 22, 1938.\n\nPublished - 1.1752357.pdf
", "abstract": "In the transmission type curved crystal focusing x-ray\nspectrograph, a crystalline lamina is imprisoned between\nthe convex and concave surfaces of two rigid metal plates\ncut in the shape of arcs of right circular cylinders of appropriate\nradius to impose the correct curvature on the\nlamina. Recently I have sought a method of cutting such\ncircular cylindrical arcs of very large radius of curvature\n(say 2 meters) without the delay and expense involved in\nthe use of a large vertical boring mill of four meters diameter.\nThe method which I describe here might also prove\nof use in the production of circular cylindrical arcs of metal\nfor lapping cylindrical lenses.", "date": "1938-10", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "9", "number": "10", "publisher": "American Institute of Physics", "pagerange": "329", "id_number": "CaltechAUTHORS:20140624-081334983", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-081334983", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.1752357", "primary_object": { "basename": "1.1752357.pdf", "url": "https://authors.library.caltech.edu/records/063z4-etr67/files/1.1752357.pdf" }, "resource_type": "article", "pub_year": "1938", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/keskw-qmx67", "eprint_id": 46440, "eprint_status": "archive", "datestamp": "2023-08-19 00:38:13", "lastmod": "2023-10-26 19:45:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "The \"Palace of Discovery\" at the Paris Exposition of 1937", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1938 American Institute of Physics.\n\nPublished - 1.1710418.pdf
", "abstract": "During the summer of 1937 it was my\npleasure and privilege to visit on many\noccasions the \"Palace of Discovery\" of the Paris\nExposition. This vast, splendid and instructive\nexhibit of scientific principles and progress was\nessentially the idea of that \"grand old man\" of\nFrench science, Jean Perrin. The details were\nadmirably worked out with the wholehearted\ncooperation of many of the most important\nFrench scientific workers who gave freely of\ntheir time and energy.", "date": "1938-05", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "9", "number": "5", "publisher": "American Institute of Physics", "pagerange": "289-294", "id_number": "CaltechAUTHORS:20140623-134516545", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140623-134516545", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.1710418", "primary_object": { "basename": "1.1710418.pdf", "url": "https://authors.library.caltech.edu/records/keskw-qmx67/files/1.1710418.pdf" }, "resource_type": "article", "pub_year": "1938", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/akse6-ke167", "eprint_id": 46456, "eprint_status": "archive", "datestamp": "2023-08-19 00:35:07", "lastmod": "2023-10-26 19:45:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Youtz-J-P", "name": { "family": "Youtz", "given": "J. Paul" } } ] }, "title": "The Thirty Kilowatt Continuous Input X\u2010Ray Equipment and High Constant Voltage Generating Plant of the Watters Memorial Research Laboratory at the California Institute of Technology", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1937 American Institute of Physics.\n\nReceived May 5, 1937.\n\nNearly all the parts of the equipment here\ndescribed were built in our own shops over a\nperiod of several years by the writers and their\nco-workers many of whom have since left this\ninstitute. Among those whom we wish especially\nto thank for their long continued, devoted and\nable assistance are Mr. Eric Howse, Mr. Bernard\nLocher, Mr. Lowell Hand, Mr. William\nPickels and Dr. Vernon Bollman. We are grateful\nalso for the briefer but equally generous aid\ngiven by Mr. William Harper and Mr. Maxwell\nKelch.\n\nThe equipment we have described is known as\nthe Watters Memorial Laboratory equipment\nof California Institute of Technology. The funds\nwhich made the construction of this equipment\npossible and which have for several years also\nsupported a number of pieces of experimental\nresearch in pure physics were given to this\nInstitute by Dr. Leon L. Watters of New York\nCity as a memorial to his wife Frances H. Watters\nand it is a pleasure to here express our gratitude\nfor his generous gift.\n\nPublished - 1.1752317.pdf
", "abstract": "This report describes in detail with photographs and cross\u2010sectional views an x-ray tube with a gyrating water\u2010cooled target which the authors have operated continuously for periods of hours at 287,000 volts and 105 milliamperes. The theoretical predictions of DuMond, Watson and Hicks as to the ratio of safe load in moving and fixed targets seems to be roughly fulfilled by these results. The computed power output in the form of x-rays alone is some 3/4 kilowatt. The report further describes in detail the power supply equipment consisting of a synchronous motor driven 40 kw motor generator set giving 150 cycle current both half-waves of which, after transformation to high voltage, are rectified by two thermionic valves (filament emission 2 amperes maximum) of our own design and construction here fully described. The powerful electrical filter system to reduce the ripple to a low value and some technical problems arising from the large power rating of the equipment as well as the facilities now almost completed for stabilizing and measuring precisely the high voltage supplied to the x\u2010ray tube are discussed. At the outset a brief indication of the program of research work projected for this set is given.", "date": "1937-08", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "8", "number": "8", "publisher": "American Institute of Physics", "pagerange": "291-307", "id_number": "CaltechAUTHORS:20140624-075853098", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140624-075853098", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Leon L. Watters" } ] }, "doi": "10.1063/1.1752317", "primary_object": { "basename": "1.1752317.pdf", "url": "https://authors.library.caltech.edu/records/akse6-ke167/files/1.1752317.pdf" }, "resource_type": "article", "pub_year": "1937", "author_list": "DuMond, Jesse W. M. and Youtz, J. Paul" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/16axb-yy562", "eprint_id": 46453, "eprint_status": "archive", "datestamp": "2023-08-19 00:34:03", "lastmod": "2023-10-26 19:45:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Marlow-D", "name": { "family": "Marlow", "given": "Douglas" } } ] }, "title": "A precision two crystal x-ray spectrometer of wide applicability with worm wheel drive; An improved precise method of equalizing the spacing of worm wheel teeth", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1937 American Institute of Physics.\n\nReceived December 12, 1936.\n\nWe are indebted to Dr. G. H. Worrall of the\nMitchell Camera Corporation of Hollywood for\nhis kind cooperation in hobbing these worm\nwheels on a precision Barber Coleman hobbing\nmachine. We thank Dr. John Anderson and\nDr. W. V. Houston for lending us the necessary\noptical parts for testing the worm wheels.\nThe staff entrusted with the construction of\nthe 200-inch telescope has on the strength of\nour present results decided to adopt the method\nhere described to originate precision in the large\ntelescope driving worm wheels and we thank\nthem for their very stimulating and helpful\ninterest.\n\nThe funds for the construction of this spectrometer\nwere derived from the gift of Leon L.\nWatters of New York City known as the\nWatters' Memorial Research Fund, given as a\nmemorial to Dr. Watters' wife, Frances Hayes\nWatters. We are grateful for this opportunity to\nexpress our appreciation of his gift.\n\nPublished - 1.1752253.pdf
", "abstract": "This article describes the design and construction of a two crystal x\u2010ray spectrometer for the study of radiation of wave\u2010length from (but not including) the vacuum region to about 100 X.U. Versatility coupled with precision of angular measurement is obtained by the use of worm gears, the spacing of whose teeth has been corrected by a relatively cheap but effective lapping method herein described.", "date": "1937-04", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "8", "number": "4", "publisher": "American Institute of Physics", "pagerange": "112-121", "id_number": "CaltechAUTHORS:20140623-153755590", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140623-153755590", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Leon L. Watters" } ] }, "doi": "10.1063/1.1752253", "primary_object": { "basename": "1.1752253.pdf", "url": "https://authors.library.caltech.edu/records/16axb-yy562/files/1.1752253.pdf" }, "resource_type": "article", "pub_year": "1937", "author_list": "DuMond, Jesse W. M. and Marlow, Douglas" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/41ew6-s7s88", "eprint_id": 46445, "eprint_status": "archive", "datestamp": "2023-08-19 00:27:26", "lastmod": "2023-10-26 19:45:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Pickels-W-M-Jr", "name": { "family": "Pickels", "given": "W. M., Jr." } } ] }, "title": "Superiority of a Knudsen type vacuum gauge for large metal systems with organic vapor pumps; Its design and operation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1935 American Institute of Physics. \n\nWe take pleasure in acknowledging our grateful indebtedness to Dr. Leon L. Watters of New York City for the funds given as a memorial to his wife, Frances H. Watters, which have made possible the entire program of research of which this investigation forms a part.\n\nPublished - 1.1751900.pdf
", "abstract": "The McLeod, Pirani, Knudsen and ionization gauges have been studied as to their suitability in the operation of large metal vacuum systems with organic vapor pumps now coming into extensive use in modern physics. Advantages and disadvantages of each type based on our experience are critically discussed. The superiority of a gauge on the Knudsen principle for this work is stressed and we present a new design and a simpler mode of operation of such a gauge together with a full discussion of its construction, calibration and characteristics.", "date": "1935-11", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "6", "number": "11", "publisher": "American Institute of Physics", "pagerange": "362-370", "id_number": "CaltechAUTHORS:20140623-142056291", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140623-142056291", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Leon L. Watters" } ] }, "doi": "10.1063/1.1751900", "primary_object": { "basename": "1.1751900.pdf", "url": "https://authors.library.caltech.edu/records/41ew6-s7s88/files/1.1751900.pdf" }, "resource_type": "article", "pub_year": "1935", "author_list": "DuMond, Jesse W. M. and Pickels, W. M., Jr." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/akwrr-xkb08", "eprint_id": 46448, "eprint_status": "archive", "datestamp": "2023-08-19 00:26:33", "lastmod": "2023-10-26 19:45:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Two applications of the sylphon bellows in high vacuum plumbing", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1935 American Institute of Physics. \n\nReceived July 29, 1935.\n\nPublished - 1.1752008.pdf
", "abstract": "The term \"vacuum plumbing\" is intended to express\nbriefly the mass of technique which has recently been\ndeveloped by which vacua from 10^(-4) to 10^(-6) mm Hg or\nbetter are obtained in systems mainly of metal and of large\nvolume. The large high voltage x-ray tubes and ion accelerating\ntubes of C. C. Lauritsen at the California Institute of\nTechnology, E. O. Lawrence at Berkeley and Merle Tuve\nat the Bureau of Terrestrial Magnetism are three examples\nof such systems.", "date": "1935-09", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "6", "number": "9", "publisher": "American Institute of Physics", "pagerange": "285-286", "id_number": "CaltechAUTHORS:20140623-150018912", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140623-150018912", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.1752008", "primary_object": { "basename": "1.1752008.pdf", "url": "https://authors.library.caltech.edu/records/akwrr-xkb08/files/1.1752008.pdf" }, "resource_type": "article", "pub_year": "1935", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/g8cqa-6m729", "eprint_id": 46446, "eprint_status": "archive", "datestamp": "2023-08-19 00:25:43", "lastmod": "2023-10-26 19:45:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Watson-B-B", "name": { "family": "Watson", "given": "Bernard B." } }, { "id": "Hicks-B", "name": { "family": "Hicks", "given": "Bruce" } } ] }, "title": "Temperatures of continuously operated mobile x-ray focal spots", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1935 American Institute of Physics.\n\nReceived May 2, 1935.\n\nIn conclusion we wish to express our appreciation\nto Dr. Morgan Ward, Dr. W. V. Houston\nand Dr. H. Bateman, all three of this Institute,\nfor their very helpful advice in the solution of\nthis problem and to Mr. Paul Youtz for assistance\nin the numerical computations. The construction\nat this Institute of a gyrating target\nx-ray tube whose design occasioned this mathematical\ninvestigation was made possible along\nwith the constant potential generating equipment\nlarge enough to supply it with 30 kw continuously \nthrough the generosity of Dr. Leon L. Watters\nof New York City who has established a fund for\nan atomic research laboratory at this Institute as\na memorial to his wife. A complete description\nof this equipment is soon to be published. We are\nglad of this first opportunity to express our\nheartfelt appreciation of Dr. Watters' generous\nsupport.\n\nPublished - 1.1751970.pdf
", "abstract": "We use the adjective \"mobile\" to describe a focal spot in an x\u2010ray tube which moves cyclically in a closed path relative to the target surface on which it is generated quite without reference to whether the spot be fixed or in motion with respect to the tube. Alex M\u00fcller and also A. Bouwers have made calculations of the thermal effects in such spots energized for very short fractions of one cycle of motion. This paper treats the case where the focal spot is energized continuously so that a \"steady\" state of thermal oscillation is set up. The solutions obtained refer only to conditions after this steady state of oscillation is reached. Only the ideal case of a spot of uniform intensity with sharp boundaries is treated. For simplicity the flow of heat from front target surface to cooling water is assumed one dimensional and normal to the front surface over an everywhere uniform thickness d. Curves are plotted showing the ratio of temperature rise in moving spots to that in fixed spots of the same size as a function of r the size of the spot relative to the length of path it describes and of \u03b8 a variable depending on the speed of rotation, the thickness d and the thermal constants of the target material. Curves of the ratio of permissible energy input for moving and fixed spots, respectively, as a function of the aforementioned variables are also shown. The paper gives a solution reduced to figures and curves of the heat flow equation for certain boundary conditions which to the author's knowledge has never before been obtained and therefore has some interest beyond its immediate application to x\u2010ray tubes. Certain mathematical difficulties of practical interest are also overcome in a way which may be helpful in other problems of similar nature. For the reader uninterested in mathematics the results are independently discussed in a separate section. Approximate methods are given for applying the results of the paper to targets consisting of two materials such as tungsten and copper.", "date": "1935-07", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "6", "number": "7", "publisher": "American Institute of Physics", "pagerange": "183-193", "id_number": "CaltechAUTHORS:20140623-144531863", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140623-144531863", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Leon L. Watters" } ] }, "doi": "10.1063/1.1751970", "primary_object": { "basename": "1.1751970.pdf", "url": "https://authors.library.caltech.edu/records/g8cqa-6m729/files/1.1751970.pdf" }, "resource_type": "article", "pub_year": "1935", "author_list": "DuMond, Jesse W. M.; Watson, Bernard B.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/a0gm2-peg69", "eprint_id": 12103, "eprint_status": "archive", "datestamp": "2023-08-21 21:27:24", "lastmod": "2023-10-17 16:31:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Kirkpatrick-H-A", "name": { "family": "Kirkpatrick", "given": "Harry A." } }, { "id": "Alden-L", "name": { "family": "Alden", "given": "Lucas" } } ] }, "title": "A search for preferentially directed electron velocities in crystalline graphite with the multicrystal spectrograph", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1932 by The American Physical Society. \n\nReceived 8 March 1932. \n\nThis investigation which has involved a great deal of expense has been carried out with the aid of funds from the Seeley W. Mudd X-Ray Research Fund and we take this opportunity to express our sincere appreciation for this financial aid.\n\nPublished - DUMpr32b.pdf
", "abstract": "The author's theory of the broadening of the Compton line as a Doppler effect of electron velocities is briefly reviewed and it is pointed out that only the component velocity along a direction which nearly bisects the angle between primary and scattered x-ray beams should be effective in broadening the line. Crystalline Ceylon graphite possesses properties which lend hope to the belief that a class of weakly bound or structure electrons in this crystal might have momenta restricted uniquely to parallelism with one plane in the crystal: the (0001) plane. A composite scatterer was built up out of blocks consisting of the crystal flakes all orientated with their (0001) planes in mutual parallelism and the blocks in turn were so orientated that the normals to these planes bisected the angle formed by the primary and scattered x-ray beams. If the electron momenta are orientated parallel to the plane of the graphite flakes one should expect the contribution of such electrons to the shifted scattering to give a sharp line or peak superposed on the broader structure caused by the remaining isotropically distributed momenta. Details of the experimental set-up are described and the spectrum obtained from scattering by the Ceylon graphite scatterer is compared with the spectrum from an isotropic Acheson graphite scatterer. The breadth and structure of the shifted line proves to be quite identical in the two cases and the conclusion is drawn that if a class of electrons having selectively orientated momenta exists in the crystal-line graphite it constitutes less than 5 percent of the total number. The bearing of this result on related questions is discussed.", "date": "1932-04-15", "date_type": "published", "publication": "Physical Review", "volume": "40", "number": "2", "publisher": "American Physical Society", "pagerange": "165-177", "id_number": "CaltechAUTHORS:DUMpr32b", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr32b", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Seeley W. Mudd X-Ray Research Fund" } ] }, "doi": "10.1103/PhysRev.40.165", "primary_object": { "basename": "DUMpr32b.pdf", "url": "https://authors.library.caltech.edu/records/a0gm2-peg69/files/DUMpr32b.pdf" }, "resource_type": "article", "pub_year": "1932", "author_list": "DuMond, Jesse W. M.; Kirkpatrick, Harry A.; et el." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/7j11z-3zg94", "eprint_id": 5820, "eprint_status": "archive", "datestamp": "2023-08-21 21:25:53", "lastmod": "2023-10-16 19:55:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Possible narrowing of Compton line breadth by preferentially directed electron momenta in Ceylon graphite", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91932 The American Physical Society. \n\nReceived 5 December 1931.", "abstract": "According to a theory of the author first published in Phys. Rev. 33, 643 (1929), the considerable natural spectral breadth of the Compton modified line was ascribed to the initial momenta of electrons in the scattering body and as one consequence a mathematical expression was derived for the behavior of this breadth as a function of the primary wavelength and scattering angle (formula 23, page 657, above article).", "date": "1932-01-01", "date_type": "published", "publication": "Physical Review", "volume": "39", "number": "1", "publisher": "Physical Review", "pagerange": "166-168", "id_number": "CaltechAUTHORS:DUNpr32a", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUNpr32a", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.39.166", "primary_object": { "basename": "DUNpr32a.pdf", "url": "https://authors.library.caltech.edu/records/7j11z-3zg94/files/DUNpr32a.pdf" }, "resource_type": "article", "pub_year": "1932", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/1pekp-ag092", "eprint_id": 7071, "eprint_status": "archive", "datestamp": "2023-08-21 21:24:34", "lastmod": "2023-10-16 20:41:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Kirkpatrick-H-A", "name": { "family": "Kirkpatrick", "given": "Harry A." } } ] }, "title": "Dependence of Compton line breadth on primary wave-length with the multi-crystal spectrograph", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91931 The American Physical Society. \n\nReceived 11 August 1931. \n\nIn conclusion we wish to express our deep appreciation of the facilities put at our disposal by the Norman Bridge Laboratory and of the interest and encouragement given us by Dr. R.A. Millikan. This investigation which has involved a great deal of expense has been carried out with the aid of the Seeley W. Mudd X-Ray Research Fund. We take this opportunity to express our gratitude for this financial aid.", "abstract": "The present report is a continuation of the work reported previously. The main purpose of the research is to test the correctness of the assumption that the initial velocities of electrons in the scattering body cause the observed breadth of the Compton shifted line. In the previous paper the natural breadths of the Compton line were observed for different angles of scattering and the breadth was found to obey the functional dependence on scattering angle predicted by DuMond on the assumption that electron velocities cause the breadth. According to DuMond's theory the breadth should also be nearly proportional to the primary wave-length. This point is tested in the present paper. Exposures of about one thousand hours each were made with characteristic K radiation from molybdenum, silver and tungsten target tubes. In each case the radiation was scattered from a graphite scatterer at a very well defined large scattering angle of 156\u00b0, the multicrystal spectrograph being used to analyze the scattered radiation. Reproductions of the photographic spectrograms are shown and also microphotometer curves of the spectra. The breadth of the Compton line is found to diminish with shorter primary wave-lengths in complete accord with the predictions of DuMond's theory. Unless some other cause can be found to explain the observed behavior of the breadth the results of this paper and the above mentioned previous paper constitute a complete vindication of this theory and of its basic assumption that the initial velocities of the electrons in the scatterer cause the breadth of the Compton shifted line. If this is correct, then these experiments constitute direct experimental evidence of the dynamic nature of atoms. The Compton shifted line can indeed be thought of as broadened by the Doppler effect of the motion of the scattering electrons. A simplified form of the theory of modified scattering by initially moving electrons is presented to supplement and clarify the more elaborate and exact theory of the previous paper. We call attention to the fact that the theory and experimental results are in no way discordant with wave mechanics or the uncertainty principle but we believe that to translate the present exposition into the language of wave mechanics would tend to obscure rather than clarify the picture. The results of this work are so clearly defined that the reality of the much narrower Compton lines obtained recently by several investigators seems, in our opinion, to be very doubtful.", "date": "1931-09-15", "date_type": "published", "publication": "Physical Review", "volume": "38", "number": "6", "publisher": "Physical Review", "pagerange": "1094-1108", "id_number": "CaltechAUTHORS:DUMpr31b", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr31b", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.38.1094", "primary_object": { "basename": "DUMpr31b.pdf", "url": "https://authors.library.caltech.edu/records/1pekp-ag092/files/DUMpr31b.pdf" }, "resource_type": "article", "pub_year": "1931", "author_list": "DuMond, Jesse W. M. and Kirkpatrick, Harry A." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/b2hrr-4d594", "eprint_id": 5536, "eprint_status": "archive", "datestamp": "2023-08-21 21:24:09", "lastmod": "2023-10-16 19:16:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Hoyt-A", "name": { "family": "Hoyt", "given": "Archer" } } ] }, "title": "A new K-Series x-ray line due to Fermi-Sommerfeld electrons", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91931 The American Physical Society. \n\nReceived 18 July 1931.", "abstract": "Duane(1) has recently reported the observation of a new K-series line or band situated between the familiar gamma line and the critical limit of the K-series (position of the K absorption discontinuity.) This band is of great interest because in all probability it can be ascribed to transitions to the K level of electrons which in their initial state are dissociated from particular atoms and from a group resembling that predicted by Sommerfeld based on the Fermi statistics.", "date": "1931-08-15", "date_type": "published", "publication": "Physical Review", "volume": "38", "number": "4", "publisher": "Physical Review", "pagerange": "839-841", "id_number": "CaltechAUTHORS:DUMpr31a", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr31a", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.38.839", "primary_object": { "basename": "DUMpr31a.pdf", "url": "https://authors.library.caltech.edu/records/b2hrr-4d594/files/DUMpr31a.pdf" }, "resource_type": "article", "pub_year": "1931", "author_list": "DuMond, Jesse W. M. and Hoyt, Archer" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/8kw3w-8b859", "eprint_id": 6135, "eprint_status": "archive", "datestamp": "2023-08-21 21:23:13", "lastmod": "2023-10-16 20:09:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hoyt-A", "name": { "family": "Hoyt", "given": "Archer" } }, { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse" } } ] }, "title": "Breadth of the Compton modified line with the double crystal spectrometer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91931 The American Physical Society. \n\nReceived 20 April 1931.", "abstract": "Three experimenters using the double crystal spectrometer have recently reported very much narrower structure for the Compton modified line than the structure observed photographically by DuMond and Kirkpatrick with the multicrystal spectrograph whose resolution was entirely adequate to reveal such a narrow structure. We have repeated the experiment using a double crystal spectrometer similar to theirs. The results obtained are in satisfactory agreement with the previous observations of Compton line breadth by DuMond and Kirkpatrick with the multicrystal spectrograph and in disagreement with the experimenters who used double crystal spectrometers. The conclusions drawn are: (1) The Compton modified line due to Mo K\u03b1 radiation scattered by graphite at angles of 165\u00b0 \u00b1 10\u00b0 and examined with the double crystal spectrometer has a breadth of from 21 to 22 XU at half-maximum height; (2) Under the above conditions there is no appreciable separation of the K\u03b1 doublet in the shifted position; (3) No fine structure exists in the scattered spectrum of intensity greater than one-fifth the modified line intensity; (4) The ratio of modified to unmodified line intensity is estimated at (7.3:1); (5) There appears to be no essential difference between the results obtained with the single crystal, multicrystal and double crystal spectrometers in the study of this problem.", "date": "1931-06-01", "date_type": "published", "publication": "Physical Review", "volume": "37", "number": "11", "publisher": "Physical Review", "pagerange": "1443-1451", "id_number": "CaltechAUTHORS:HOYpr31", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:HOYpr31", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.37.1443", "primary_object": { "basename": "HOYpr31.pdf", "url": "https://authors.library.caltech.edu/records/8kw3w-8b859/files/HOYpr31.pdf" }, "resource_type": "article", "pub_year": "1931", "author_list": "Hoyt, Archer and DuMond, Jesse" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ynfg9-khn53", "eprint_id": 2600, "eprint_status": "archive", "datestamp": "2023-08-21 21:21:57", "lastmod": "2023-10-13 23:37:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Kirkpatrick-H-A", "name": { "family": "Kirkpatrick", "given": "Harry A." } } ] }, "title": "Experimental evidence for electron velocities as the cause of Compton line breadth with the multicrystal spectrograph", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91931 The American Physical Society. \n\nReceived 1 December 1930. \n\nIn conclusion we wish to express our appreciation of Dr. Millikan's support of this research and of the patience and skill of Julius Pearson, our instrument maker, who developed the technique and did the tedious work of grinding and fitting the small calcite units into their bodies.", "abstract": "The main purpose of this research was to test the correctness of the assumption that the initial velocities of electrons in the scattering body cause the observed breadth of the Compton shifted line. The test consists in observing the natural breadths of the Compton line for different scattering angles and primary wave-lengths and comparing these with the functional dependence of breadth on scattering angle and primary wave-length deduced theoretically on the basis of the assumption under test. It is shown in this paper that if electron velocities are the cause of the breadth then this breadth should increase with the scattering angle according to the approximate formula \u0394\u03bb=Kcos1/2\u03b8 where \u0394\u03bb is the breadth, \u03b8 the scattering angle and K a constant depending on the primary wave-length and the scattering substance. For the same scattering angle and substance the breadth should be proportional to the primary wave-length. \n\nThe experimental test was made with the multicrystal spectrograph of fifty units herein briefly described. Three scattering angles were used, 63\u00bd\u00b0, 90\u00b0, 156\u00b0, the inhomogeneity in each case being less than one degree. The spurious breadth due to this inhomogeneity is negligible compared to the observed breadths. Three very clear cut spectrograms are reproduced representing MoK radiation scattered from graphite together with microphotometer curves taken from them. The increase of shifted line breadth with scattering angle is clearly visible and compares favorably with the theoretical prediction. The increase of line breadth with increasing primary wave-length comparing the breadths of shifted \u03b11 and shifted \u03b21 lines seems just detectable. The unshifted lines are very sharp, the \u03b1 doublet being clearly resolved. Incidentally the cause of the heavy background so frequently observed on Compton effect spectrograms has been found to be non-selective scattering at the crystals and a great reduction of background and improvement in contrast has been effected by the use of baffles to diminish this effect.\n\nThe observed shift of the Compton line supports Compton's formula \u03b4\u03bb=(h/mc)(1-cos\u03b8) where h/mc=24.2X.U. \n\nThe shifted line breadths are greater than those reported by Gingrich and Bearden and possibly Ross but seem to be in general accord with previous breadths obtained at this laboratory and with those of H. M. Sharp and of F. L. Nutting. The reason for these discrepancies is unknown. The possibility of double or higher multiplicities of scattering is being investigated. (See note added in proof at the end of this article.)", "date": "1931-01-15", "date_type": "published", "publication": "Physical Review", "volume": "37", "number": "2", "publisher": "Physical Review", "pagerange": "136-159", "id_number": "CaltechAUTHORS:DUMpr31", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr31", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.37.136", "primary_object": { "basename": "DUMpr31.pdf", "url": "https://authors.library.caltech.edu/records/ynfg9-khn53/files/DUMpr31.pdf" }, "resource_type": "article", "pub_year": "1931", "author_list": "DuMond, Jesse W. M. and Kirkpatrick, Harry A." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/vtpta-8ej96", "eprint_id": 2598, "eprint_status": "archive", "datestamp": "2023-08-21 21:21:37", "lastmod": "2023-10-13 23:37:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Hoyt-A", "name": { "family": "Hoyt", "given": "Archer" } } ] }, "title": "Design and technique of operation of a double crystal spectrometer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91930 The American Physical Society. \n\nReceived 8 November 1930.", "abstract": "The double crystal x-ray spectrometer is distinctly different in principle from the single crystal spectrometer and calls therefore for a completely new design rather than an adaptation of single spectrometer design. One such new design is described in this paper. Emphasis is laid on the fact that the wave-length selected by the process of two successive crystal reflections in any prescribed orders depends solely on the dihedral angle between the crystals. The advantages of rotating both crystals in equal and opposite directions with respect to a plane through their axes of rotation are pointed out and a spectrometer designed to accomplish this is described. In this spectrometer the turning of a single shaft drives the two crystals, the spectrometer as a whole and the x-ray tube, at the proper angular rates about the proper centers to insure that the x-ray beam will at all times remain centered on the crystal faces and the window of the stationary ion chamber. It is pointed out that spurious fluctuations may be introduced in spectral curves by the x-ray beam migrating across small steps in the cleavage surface reflecting the radiation. Description of design covers design of spectrometer and turning mechanisms, the tube housing, lead shields, the detecting system consisting of an ion chamber with internal grid of special design to minimize natural leak and a Hoffmann vacuum electrometer connected to it through a short evacuated shield. Description of operating technique covers optical method of accurately orienting the crystal faces, methods of aligning the tube, precautions to eliminate background.", "date": "1930-12-15", "date_type": "published", "publication": "Physical Review", "volume": "36", "number": "12", "publisher": "Physical Review", "pagerange": "1702-1720", "id_number": "CaltechAUTHORS:DUMpr30d", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr30d", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.36.1702", "primary_object": { "basename": "DUMpr30d.pdf", "url": "https://authors.library.caltech.edu/records/vtpta-8ej96/files/DUMpr30d.pdf" }, "resource_type": "article", "pub_year": "1930", "author_list": "DuMond, Jesse W. M. and Hoyt, Archer" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/smva3-dmj51", "eprint_id": 2599, "eprint_status": "archive", "datestamp": "2023-08-21 21:21:42", "lastmod": "2023-10-13 23:37:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Multiple scattering in the Compton effect", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91930 The American Physical Society. \n\nReceived 5 November 1930.", "abstract": "In the experimental study of the spectral distribution of x-radiation scattered by light elements it has always, up to the present, been assumed that multiple scattering could be neglected. Recent improvements in experimental technique however make it possible to suppose that multiple (especially double) scattering may now be detectable from large scattering bodies. Multiple scattering may (1) affect the breadth of the modified line, (2) change the structure of the modified line, (3) distort the background in such a way as to render measurements of shift unreliable. It is therefore valuable to analyze the effect of multiple scattering in case some of the recent mutually discordant experimental results may be explained and harmonized in this way.\n\nAssuming initially monochromatic radiation, scattering of any degree of multiplicity contributes a spectral band whose wave-length limits are here determined and discussed. The Breit, Compton, Jauncey formula taking polarization into account is adopted for the purposes of calculation of modified intensity. The results are thus fairly accurate for hard radiation scattered from very light elements. For softer radiation modified scattering at small scattering angles is greatly reduced below the values given by the Breit, Compton, Jauncey formula and unmodified scattering appears. The effect of this on the results of this paper is discussed in a qualitative way.\n\nThe case of double scattering from a spherical scatterer is computed in complete detail and a formula for the ratio of double to single scattering is derived. Curves of the spectral distributions due to double scattering are shown. The dependence of the total doubly scattered intensity on the primary scattering angle is plotted.\n\nThe natural width of the modified line is neglected throughout these calculations. Absorption in the scatterer is also neglected. The ratio of double to single scattering for a spherical scatterer observed under any given angle is proportional to the radius of the scatterer (neglecting absorption) and is given by Doubly scattered energy /Singly scattered energy =9/32\u03c3rR(\u03b8)\n\nwhere \u03c3 is the linear scattering coefficient for the material of the scattering sphere, r the radius of the sphere, \u03b8 the angle under which single scattering occurs. R(\u03b8) never differs greatly from 2.5.\n\nTriple scattering is negligible in comparison to single scattering.\n\nTwice modified doubly scattered radiation may contribute a faint asymmetric line or edge at the shifted position \u0394\u03bb=2(h/mc)(1+cos1/2\u03b8)\n\nFor hard radiation when the Thompson formula (with Breit correction) applies with fair accuracy to modified scattering alone twice modified doubly scattered radiation contributes a spectral band of breadth 4(h/mc) cos1/2\u03b8\n\nOnce modified doubly scattered radiation may cause a slight broadening of the Compton line except in regions near \u03b8=0 and \u03b8=180\u00b0.", "date": "1930-12-15", "date_type": "published", "publication": "Physical Review", "volume": "36", "number": "12", "publisher": "Physical Review", "pagerange": "1685-1701", "id_number": "CaltechAUTHORS:DUMpr30e", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr30e", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.36.1685", "primary_object": { "basename": "DUMpr30e.pdf", "url": "https://authors.library.caltech.edu/records/smva3-dmj51/files/DUMpr30e.pdf" }, "resource_type": "article", "pub_year": "1930", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/3606b-nvh58", "eprint_id": 2587, "eprint_status": "archive", "datestamp": "2023-08-21 21:19:34", "lastmod": "2023-10-13 23:37:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Hoyt-A", "name": { "family": "Hoyt", "given": "Archer" } } ] }, "title": "Energy of Kappa alpha(3) of copper as a function of applied voltage with the double crystal spectrometer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91930 The American Physical Society. \n\nReceived 22 July 1930.", "abstract": "With a double crystal spectrometer of special design here briefly described the following questions were investigated with a view to determining the origin of the satellite K\u03b13 of copper. (1) Dependence of intensity of satellite K\u03b13 of copper on voltage with constant current. (2) Dependence of intensity of parent line K\u03b11 of copper on voltage with constant current. (3) Ratio of intensities of satellite to parent. (4) Dependence of satellite intensity on current at constant voltage. The conclusions are (1) that the satellite is excited at a voltage differing from the excitation voltage of the parent line by too small an amount to be measured with certainty (less than 200 volts). (2) That the ratio of intensities of \u03b11 to \u03b13 as estimated from the areas of the spectral line structures is about 1:120. (3) That the intensity of the satellite K\u03b13 of copper is strictly proportional to the current at constant voltage. These facts seem to invalidate the Wentzel-Druyvesteyn \"spark line\" hypothesis as an explanation of K\u03b13 of copper. Richtmyer's \"double jump\" hypothesis remains tenable. In addition a doublet structure (separation of components about 2 X.U.) in K\u03b13 of copper was observed (in accord with the doublet structure of this satellite in elements of lower atomic number).", "date": "1930-09-01", "date_type": "published", "publication": "Physical Review", "volume": "36", "number": "5", "publisher": "Physical Review", "pagerange": "799-809", "id_number": "CaltechAUTHORS:DUMpr30b", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr30b", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.36.799", "primary_object": { "basename": "DUMpr30b.pdf", "url": "https://authors.library.caltech.edu/records/3606b-nvh58/files/DUMpr30b.pdf" }, "resource_type": "article", "pub_year": "1930", "author_list": "DuMond, Jesse W. M. and Hoyt, Archer" }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/w8jst-tn884", "eprint_id": 2588, "eprint_status": "archive", "datestamp": "2023-08-21 21:19:39", "lastmod": "2023-10-13 23:37:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "Evidence for the Richtmyer double jump hypothesis of x-ray satellites", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91930 The American Physical Society. \n\nReceived 6 August 1930.", "abstract": "Richtmyer(1) has recently proposed the hypothesis that many of the x-ray satellite lines may be due to double transitions in which two electron transitions cooperate to emit one quantum. I should like to call attention to a number of known facts about x-ray satellites which are very satisfactorily explained on this hypothesis several of which facts have not yet been mentioned by Richtmyer.", "date": "1930-09-01", "date_type": "published", "publication": "Physical Review", "volume": "36", "number": "5", "publisher": "Physical Review", "pagerange": "1015-1017", "id_number": "CaltechAUTHORS:DUMpr30c", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr30c", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.36.1015", "primary_object": { "basename": "DUMpr30c.pdf", "url": "https://authors.library.caltech.edu/records/w8jst-tn884/files/DUMpr30c.pdf" }, "resource_type": "article", "pub_year": "1930", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/pjmxw-2ha09", "eprint_id": 2581, "eprint_status": "archive", "datestamp": "2023-08-21 21:18:38", "lastmod": "2023-10-13 23:37:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "J. W. M." } } ] }, "title": "Breadth of Compton modified line", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91930 The American Physical Society. \n\nReceived 20 June 1930.", "abstract": "Professors Ross and Clark of Stanford, using the ingenious balanced filter method of Ross, have investigated the shifted line in the Compton effect for antimony, K\u03b11 and K\u03b12, lines scattered from beryllium. In this method the scattering angle is varied so as to vary the shift of the modified line.", "date": "1930-07-01", "date_type": "published", "publication": "Physical Review", "volume": "36", "number": "1", "publisher": "Physical Review", "pagerange": "146-147", "id_number": "CaltechAUTHORS:DUMpr30a", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr30a", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.36.146", "primary_object": { "basename": "DUMpr30a.pdf", "url": "https://authors.library.caltech.edu/records/pjmxw-2ha09/files/DUMpr30a.pdf" }, "resource_type": "article", "pub_year": "1930", "author_list": "DuMond, J. W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/ge7ra-q5x44", "eprint_id": 46442, "eprint_status": "archive", "datestamp": "2023-08-19 00:05:11", "lastmod": "2023-10-26 19:45:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "A new Parallel Plate Comparator", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1930 American Institute of Physics.\n\nPublished - 1.1748676.pdf
", "abstract": "The \"Parallel Plate Comparator\" is best adapted for measuring the\nseparation of two parallel lines (eg. spectral lines) whose structures are\npractically identical and which are on the same negative and only a few\nmillimeters apart. It consists of two plane parallel plates of glass\nattached to a mechanism such that they can be set at equal and opposite\nangles with the plane of the negative. The two equal and opposite\nangles between the plates and the negative must lie in a plane normal\nto the lines whose separation is to be measured. The lines are viewed\nthrough the inclined glass plates with a long focus microscope having a\nsufficiently large field to include both plates and both lines. The lines\nare brought into apparent coincidence in the field of the microscope by\nvarying the obliquity of the glass plates to the line of sight. This obliquity\nis then a measure of the separation of the lines. If the lines are of\nidentical structure and intensity, even though they are not symmetrical\nin structure, much greater precision is possible by bringing them into\napparent coincidence than by attempting to set a crosshair first on one\nline and and then on the other. (The lines should be photographed or\nblocked off so that the upper half of one and the lower half of the other\nonly is visible. The slightest fault in the apparent coincidence of the ends\nof the two half lines is then glaringly evident through the microscope.\nWhen coincidence is obtained, the two half lines give a good photometric\nmatch across their juncture and appear as one. In a properly designed\ninstrument, the crack separating the two plane parallel glass plates is\ninvisible because it is not in the focal plan of the objective.)", "date": "1930-02", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "1", "number": "2", "publisher": "American Institute of Physics", "pagerange": "84-87", "id_number": "CaltechAUTHORS:20140623-140038596", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140623-140038596", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.1748676", "primary_object": { "basename": "1.1748676.pdf", "url": "https://authors.library.caltech.edu/records/ge7ra-q5x44/files/1.1748676.pdf" }, "resource_type": "article", "pub_year": "1930", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/93age-8zk80", "eprint_id": 46444, "eprint_status": "archive", "datestamp": "2023-08-19 00:05:16", "lastmod": "2023-10-26 19:45:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } }, { "id": "Kirkpatrick-H-A", "name": { "family": "Kirkpatrick", "given": "Harry A." } } ] }, "title": "The multiple crystal x-ray spectrograph", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1930 American Institute of Physics.\n\nPublished - 1.1748677.pdf
", "abstract": "The need for improvements in scattered x-ray spectroscopic technique along the lines\nof increased intensity and contrast is discussed and a new instrument composed of fifty small\nunits, each a Seeman Spectrograph in itself cooperating to form a single spectrogram, is\ndescribed in detail. The technique of adjusting the instrument is also described.", "date": "1930-02", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "1", "number": "2", "publisher": "American Institute of Physics", "pagerange": "88-105", "id_number": "CaltechAUTHORS:20140623-141533773", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140623-141533773", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1063/1.1748677", "primary_object": { "basename": "1.1748677.pdf", "url": "https://authors.library.caltech.edu/records/93age-8zk80/files/1.1748677.pdf" }, "resource_type": "article", "pub_year": "1930", "author_list": "DuMond, Jesse W. M. and Kirkpatrick, Harry A." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/25zfy-asb62", "eprint_id": 4896, "eprint_status": "archive", "datestamp": "2023-08-21 21:12:09", "lastmod": "2023-10-16 17:59:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "Du Mond", "given": "Jesse W. M." } } ] }, "title": "Compton modified line structure and its relation to the electron theory of solid bodies", "ispublished": "pub", "full_text_status": "public", "note": "\u00a91929 The American Physical Society. \n\nReceived 10 February 1929. \n\nMy sincere thanks are due to Professor W. V. Houston for his kindness in acquainting me with the results of the electron theory of metals in the Fermi statistics, and to Professor L. C. Pauling and Mr. Edwin McMillan for the help they gave me in the development and computation of the functions \u03a6(\u03b2) for wave mechanical atom odels. I am much indebted to Professor George Wentzel for his discussions and criticism in conversations in Paris and in subsequent letters. I am most grateful, also, to Professor R. A. Millikan for his faith and encouragement in this study which for a long time gave but meager promise of interesting results.", "abstract": "A tube especially designed for the study of the Compton effect at large angles of scattering.\u2014The structure of the Compton line obtained with this tube for a scattering angle of nearly 180\u00b0 with a metallic beryllium scatterer is shown. \n\nInterpretation of the structure of the Compton line.\u2014The diffuse structure of the Compton line is here attributed to a broadening caused by the velocity distribution of the scattering electrons in the solid scatterer analagous to a Doppler broadening and a relation between line structure and velocity distribution is derived. The observed line structure from the beryllium scatterer is compared with theoretical structures computed on several alternative assumptions as to electron velocity distribution. It is assumed: \u20141. That electrons in the solid scattering substance have the velocity distribution required by a wave-mechanical atom model for a free atom of that substance far removed from neighbors. 2. That electrons may be divided into two classes, one class the metallic or conductive electrons in the state of a degenerate electron gas subject to the Pauli Exclusion Principle and having the velocity distribution derived by Sommerfeld, and the other class as in the 1st assumption unperturbed by the neighboring atoms. 3. That electrons may be divided into two classes as before but that those forming an electron gas have the classical velocity distribution required by the Maxwell-Boltzmann equipartition law. 4. That electrons have the velocity distribution required by the older Bohr-Sommerfeld atom model with point electrons executing Kepler orbits and as in the first assumption unperturbed by neighboring atoms. \n\nThe distribution of electron velocities in metals.\u2014The results strongly contradict the classical distribution of electron velocities in solid bodies predicted by the rigid interpretation of the Maxwell-Boltzmann equipartition principle. They are also in contradiction with the older Bohr-Sommerfeld atom model. The results are in accord with the wave-mechanical atom model and constitute favorable evidence for the Sommerfeld distribution of metallic electron velocities and for the degenerate gas state.", "date": "1929-05-01", "date_type": "published", "publication": "Physical Review", "volume": "33", "number": "5", "publisher": "Physical Review", "pagerange": "643-658", "id_number": "CaltechAUTHORS:DUMpr29a", "issn": "0031-899X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpr29a", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1103/PhysRev.33.643", "primary_object": { "basename": "DUMpr29a.pdf", "url": "https://authors.library.caltech.edu/records/25zfy-asb62/files/DUMpr29a.pdf" }, "resource_type": "article", "pub_year": "1929", "author_list": "Du Mond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/d593r-e9524", "eprint_id": 10051, "eprint_status": "archive", "datestamp": "2023-08-21 21:10:16", "lastmod": "2023-10-16 22:38:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "The structure of the Compton shifted line", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1928 by the National Academy of Sciences. \n\nCommunicated October 13, 1928.", "abstract": "According to Wentzel's(1) wave mechanical theory of modified x-ray scattering and also according to Jauncey's (2) classical-quantum theory of the same effect (though not explicitly so stated by Jauncey), the modified scattered x-radiation is regarded as due to many Smekal transitions (3) in each of which the initial state of the electron is a discrete negative energy level and the final state is one of the continuum of positive energy levels. In both of these theories the shifted \"line\" is predicted as a diffuse band, the diffuseness being due to the momenta of bound electrons in the dynamic atom model. Indeed, the natural breadth of the Compton modified line can be regarded as a Doppler broadening for x-rays scattered by moving electrons in much the same way as the temperature broadening is regarded in the case of optical spectra. The broadening of the Compton line is the most direct evidence for a dynamic atom model yet found. The structure of the line can be interpreted in such a way as to give the probability distribution of electron momenta in atoms. The breadth for circular orbits should be proportional to the effective atomic number of the scatterer.", "date": "1928-11-01", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "14", "number": "11", "publisher": "National Academy of Sciences", "pagerange": "875-878", "id_number": "CaltechAUTHORS:DUMpnas28", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:DUMpnas28", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "primary_object": { "basename": "DUMpnas28.pdf", "url": "https://authors.library.caltech.edu/records/d593r-e9524/files/DUMpnas28.pdf" }, "resource_type": "article", "pub_year": "1928", "author_list": "DuMond, Jesse W. M." }, { "id": "https://authors.library.caltech.eduhttps://authors.library.caltech.edu/records/0w6k8-xhk86", "eprint_id": 81229, "eprint_status": "archive", "datestamp": "2023-08-18 23:54:58", "lastmod": "2023-10-17 19:40:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuMond-J-W-M", "name": { "family": "DuMond", "given": "Jesse W. M." } } ] }, "title": "A complex quantity slide rule", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 1925 AIEE.\n\nPublished - 06536164.pdf
", "abstract": "The need for a device to shorten numerical work with complex quantities is pointed out and a description is given of a slide rule in two dimensions devised to fill this need.", "date": "1925-02", "date_type": "published", "publication": "Journal of the A.I.E.E.", "volume": "44", "number": "2", "publisher": "AIEE", "pagerange": "133-139", "id_number": "CaltechAUTHORS:20170906-162911641", "issn": "0095-9804", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170906-162911641", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "doi": "10.1109/JAIEE.1925.6536164", "primary_object": { "basename": "06536164.pdf", "url": "https://authors.library.caltech.edu/records/0w6k8-xhk86/files/06536164.pdf" }, "resource_type": "article", "pub_year": "1925", "author_list": "DuMond, Jesse W. M." } ]