A principle for bending crystals with a minimum of strain\r\nso that they will focus x-rays and \u03b3-rays accurately to a point\r\nis explained.
\r\n\r\nDetailed calculations are made of the aberrations in the\r\nfoci resulting from various applications of the principle.
\r\n\r\nThe application of the principle in making a point focusing\r\nmonochromator for low angle x-ray diffraction studies is discussed,\r\nand theoretical and experimental determinations of the reflection\r\ncoefficient of the crystal are compared.
\r\n\r\nA few experiments in low angle diffraction from biological\r\nmaterials using the new monochromator are described, and the results\r\nare compared with those obtained using other instruments.
", "publication_date": "1955", "thesis_type": "phd", "thesis_year": "1955" }, { "id": "thesis:350", "collection": "thesis", "collection_id": "350", "cite_using_url": "https://resolver.caltech.edu/CaltechETD:etd-01262004-140923", "primary_object_url": { "basename": "Murray_jj_1954.pdf", "content": "final", "filesize": 3617905, "license": "other", "mime_type": "application/pdf", "url": "/350/1/Murray_jj_1954.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "The Decay of Ta\u00b9\u2078\u00b3", "author": [ { "family_name": "Murray", "given_name": "Joseph Jackson", "clpid": "Murray-Joseph-Jackson" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "NOTE: Text or symbols not renderable in plain ASCII are indicated by [...]. Abstract is included in .pdf document.\r\n\r\nThe [...] decay of Ta183 into an excited state of W183 has been observed using the curved crystal gamma-ray diffraction spectrometer and the axial focusing homogeneous field beta spectrometer. A unique decay scheme is presented for this mode of excitation of W183 constructed on the basis of the energies and conversion properties of twenty-seven gamma transitions with spin and parity assigned to each level. The principal features of the scheme are no parity change throughout, frequent violation of single particle selection rules, and several examples of competition between E2 and M1 transitions. These results provide amplification of and correction. to preliminary results reported earlier (Dumond, Hoyt, Marmier and Murray, Phys. Rev. 92, 202 (1953)).\r\n\r\nIn addition to the primary results above, there will also be found a comparison of the experimental and theoretical K and L conversion coefficients for E2 and M1 transitions in the energy range from 40 to 350 kev and experimental M and N conversion coefficients for a few low energy E2 and M1 transitions.\r\n\r\nThere is presented a review of the techniques employed and of important parts of the analysis of the experimental data especially with regard to corrections applied to observed intensities of gamma and conversion lines. A brief discussion offers a suggestion for possible interpretation of certain aspects of the results in terms of current ideas about, nuclear structure.", "doi": "10.7907/ZGBJ-MY29", "publication_date": "1954", "thesis_type": "phd", "thesis_year": "1954" }, { "id": "thesis:1465", "collection": "thesis", "collection_id": "1465", "cite_using_url": "https://resolver.caltech.edu/CaltechETD:etd-04232003-102801", "primary_object_url": { "basename": "Henke_b_1953.pdf", "content": "final", "filesize": 11382327, "license": "other", "mime_type": "application/pdf", "url": "/1465/1/Henke_b_1953.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "Diffraction of Long Wavelength X-Ray", "author": [ { "family_name": "Henke", "given_name": "Burton L.", "clpid": "Henke-Burton-L" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "The theory and application of diffraction by long, x-ray wavelengths are discussed. Four methods obtaining the diffraction pattern are described, namely (1) the double-crystal spectrometer, (2) the annular slit system, (3) the concave mica, point-focusing monochromator, and (4) the total-reflection, point-focusing system. The design and construction of the total-reflection equipment is described in detail. This method is applied to the measurement of the Dow latex particles.", "doi": "10.7907/2JGQ-WN90", "publication_date": "1953", "thesis_type": "phd", "thesis_year": "1953" }, { "id": "thesis:17531", "collection": "thesis", "collection_id": "17531", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:07162025-144720077", "primary_object_url": { "basename": "Wilts_JR_1952.pdf", "content": "final", "filesize": 33714072, "license": "other", "mime_type": "application/pdf", "url": "/17531/1/Wilts_JR_1952.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "Precision Measurement of Nuclear Energies Using the Non-Ferromagnetic Beta-Ray Spectrometer with Homogeneous Magnetic Field", "author": [ { "family_name": "Wilts", "given_name": "James Reed", "clpid": "Wilts-James-Reed" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "A new precision magnetic beta-ray spectrometer achieving\r\nsimultaneously both high resolution and high luminosity\r\nis presented. The theory of its operation and design by\r\nProfessor J. W. M. DuMond is traced.
\r\n\r\nSuccessful adaptation of a resonance absorption scheme\r\nusing the magnetic moment of the proton for precisely measuring \r\nand controlling the magnetic field is reported.
\r\n\r\nThe instrumental line profile is discussed. A new\r\ntype of source due to Dr. D. E. Muller is shown to simplify\r\nthe interpretation of experimental data by giving the spectral\r\nlines obtained from the conversion of nuclear gamma-rays\r\na characteristic fiducial feature of high reproducibility.
\r\n\r\nThe reproducibility of measurements claimed for the\r\ninstrument is verified by the results of a study of the\r\nThorium F and I lines. Repeated observations having a\r\nstandard deviation for a single observation of less than one\r\npart in 10,000. are obtained.
", "doi": "10.7907/s729-3424", "publication_date": "1952", "thesis_type": "phd", "thesis_year": "1952" }, { "id": "thesis:10502", "collection": "thesis", "collection_id": "10502", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:10112017-100346458", "primary_object_url": { "basename": "Hoyt_HC_1952.pdf", "content": "final", "filesize": 33280054, "license": "other", "mime_type": "application/pdf", "url": "/10502/1/Hoyt_HC_1952.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "Precision Wavelength Measurements of the Annihilation Radiation from Copper 64 and Gamma-Radiation Following Decay of Gold 198 and Tantalum 182", "author": [ { "family_name": "Hoyt", "given_name": "Harry Charles", "clpid": "Hoyt-Harry-Charles" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "The geometry, kinematics, and operation of the curved crystal\r\ngamma-ray spectrometer are briefly described. The effect of a recently\r\ndiscovered systematic non-linearity is discussed in some detail. A\r\nnew calibration of the instrument and the means taken to correct for\r\nthe non-linearity are described. Error-contributing factors are analyzed,\r\nand their contributions to the final error are estimated. The three\r\nprincipal components of the observed line profile are discussed.
\r\n\r\nA new measurement of the annihilation radiation is reported. The\r\nrelation of this measurement to the determination of the mass of the\r\npositron is discussed. Measurements of the wavelength of the 411 Kev\r\ngamma-ray line following decay of Au198 are given. Wavelengths of\r\nsixteen gamma-ray lines following decay of Ta182 are tabulated. The\r\nformulation of an energy level scheme for its daughter W182 is discussed.
", "doi": "10.7907/DY6H-6607", "publication_date": "1952", "thesis_type": "phd", "thesis_year": "1952" }, { "id": "thesis:10562", "collection": "thesis", "collection_id": "10562", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:11202017-145724629", "primary_object_url": { "basename": "Shenfil_L_1952.pdf", "content": "final", "filesize": 33317482, "license": "other", "mime_type": "application/pdf", "url": "/10562/1/Shenfil_L_1952.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "Point Focusing X-Ray Monochromator for Low Angle Scattering Studies", "author": [ { "family_name": "Shenfil", "given_name": "Leon", "clpid": "Shenfil-Leon" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "A point focusing x-ray monochromator was designed and \r\nconstructed for low angle scattering studies. The anastigmatic \r\npoint focus is achieved by means of two cylindrically bent \r\nquartz crystals whose focal circles are mutually perpendicular. \r\nThe beam, emanating from the copper target of an x-ray tube, is \r\nreflected in succession, first from the crystal defining the \r\nhorizontal focal circle and, second from the crystal defining\r\nthe vertical focal circle following which it comes to a mono\u00adchromatic \r\npoint focus of wavelength 1.537 \u00c5 (Cu K\u03b11). The \r\nsample to be studied is placed between the second crystal and\r\nthe point focus, and the scattered beam is detected by means \r\nof a photographic plate placed at the point focus, at right \r\nangles to the undeviated beam, the latter being suppressed by \r\nmeans of an absorber.
\r\n\r\n\r\nMathematical analysis, in which a ray was traced through\r\nthe two crystal system, revealed correctly the shape and size\r\nof the point focus, and the possibility of reducing the latter\r\nin size by stopping down the beam emerging from the target.
\r\n\r\n\r\nThe instrument and its lining up procedure is described\r\nin detail, particularly the latter since the orientation of\r\nthe two crystals relative to each other and the x-ray tube\r\ninvolve twelve degrees of freedom.
\r\n\r\n\r\nSuggestions for improving the intensity of the instrument\r\nare made. These consist of (1) substitution of topaz crystals\r\nfor quartz, (2) use of helium atmosphere instead of air to\r\nsurround the x-ray beam (3) reorientation of the x-ray tube\r\nto permit smaller angles of emergence of the beam.
\r\n\r\n\r\nAs a trial run for the instrument, the scattering\r\npatterns of two kinds of carbon black (good scatterers) were\r\nobtained from which the average particle sizes and size\r\ndistributions were calculated.
", "doi": "10.7907/9ZRJ-X525", "publication_date": "1952", "thesis_type": "phd", "thesis_year": "1952" }, { "id": "thesis:10459", "collection": "thesis", "collection_id": "10459", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:09262017-162449067", "primary_object_url": { "basename": "Danielson_we_1952.pdf", "content": "final", "filesize": 18761226, "license": "other", "mime_type": "application/pdf", "url": "/10459/1/Danielson_we_1952.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "Application of the Point Focusing X-Ray Monochromator to the Study of Low Angle Diffraction", "author": [ { "family_name": "Danielson", "given_name": "Warren Evald", "clpid": "Danielson-Warren-Evald" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "The geometry of the point focusing monochromator is described, and the instrument's uses in connection with low angle diffraction studies are outlined. A careful determination of the particle size of latex spheres by studies of the associated low angle diffraction pattern is made, and an experiment to determine the sensitivity of this particle size to external pressure is described. The results of an experiment in which the monochromator is used to obtain important information on the existence and nature of the collagen molecule are given. A technique for finding the size of particles whose shape is reasonably approximated by two spheroids is given, and the technique is applied to the size determination of bacteriophage type T-4. Improvements in the instrument are discussed and several suggestions for further applications are mentioned.", "doi": "10.7907/7A7G-7081", "publication_date": "1952", "thesis_type": "phd", "thesis_year": "1952" }, { "id": "thesis:10476", "collection": "thesis", "collection_id": "10476", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:10022017-160139639", "type": "thesis", "title": "A Precision Measurement of the Wavelengths of Gamma and X-Radiation Following Decay of Iridium 192 and Tungsten 187, by Means of the Focusing Crystal Diffraction Spectrometer", "author": [ { "family_name": "Muller", "given_name": "David Eugene", "clpid": "Muller-David-Eugene" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "Precision determinations of gamma ray and x-ray wavelengths\r\nin the spectra following decay of iridium 192 and tungsten 187 are\r\nrecorded. Measurements of these wavelengths were made with the\r\nfocusing crystal diffraction spectrometer.
\r\n\r\n\r\nDevelopment of a scintillation counter for use as a \r\ngamma ray detector in the spectrometer is described.
\r\n\r\n\r\nThe precision of measurements with spectrometer is analyzed;\r\nparticular attention being paid to errors resulting from\r\nstatistical variations in counting rate. Linearity of the instrument\r\nis studied by comparing measurements obtained with first, second and\r\nthird order reflections in the crystal.
\r\n\r\n\r\nGamma ray energies are combined so as to form decay schemes\r\nfor iridium 192 and tungsten 187.
", "doi": "10.7907/SB6A-0Z19", "publication_date": "1951", "thesis_type": "phd", "thesis_year": "1951" }, { "id": "thesis:17630", "collection": "thesis", "collection_id": "17630", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:08152025-205227845", "primary_object_url": { "basename": "Brown_JR_1951.pdf", "content": "final", "filesize": 32582062, "license": "other", "mime_type": "application/pdf", "url": "/17630/1/Brown_JR_1951.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "Gamma-Ray Wavelength Measurements of Gold 198, Iodine 131, Cobalt 60, and Tantalum 182 Using a Curved Crystal Focusing Spectrometer", "author": [ { "family_name": "Brown", "given_name": "James Roy", "clpid": "Brown-James-Roy" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "A description of the two-meter curved crystal\r\nfocusing spectrometer, including improvements in several\r\nof the component parts, is given. The systematic errors\r\ninherent in the measurements and the calibration necessary\r\nto determine them are discussed. The construction of a \r\nsensitive geiger counter for the detecting system was\r\nnecessary and was achieved only after many failures. The\r\nover-all instrument sensitivity is low, requiring sources\r\nof the order of twenty to fifty millicuries. The gamma-ray\r\nspectra of four sources, Gold 198, Iodine 131, Cobalt\r\n60, and Tantalum 182, were studied. In the case of Iodine\r\nand Tantalum the entire spectrum was not obtained because\r\nof the lack of sufficient source strength. The results\r\nfor all these sources and the method by which they were\r\nobtained are given.", "publication_date": "1951", "thesis_type": "phd", "thesis_year": "1951" }, { "id": "thesis:3397", "collection": "thesis", "collection_id": "3397", "cite_using_url": "https://resolver.caltech.edu/CaltechETD:etd-09092003-120209", "primary_object_url": { "basename": "Klein_dj_1951.pdf", "content": "final", "filesize": 5066062, "license": "other", "mime_type": "application/pdf", "url": "/3397/1/Klein_dj_1951.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "Precision Measurements of Gamma-Ray Wavelengths of the Radium and Thorium Series Using the Focussing Crystal Spectrometer", "author": [ { "family_name": "Klein", "given_name": "David Joseph", "clpid": "Klein-David-Joseph" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "The curved crystal spectrometer is described very briefly. The preparation and mounting of sources of radon and radiothorium for use in the instrument is described. Certain calculations of line profiles to be observed are carried out and a graphical method is given which permits rapid estimate of the important features of the profile as functions of the source geometry. The construction of multicellular Geiger counters and measurements of their efficiency are described. The results of precision measurements of five gamma-ray lines and one x-ray line of the radium spectrum are given, as well as those of site gamma-ray lines of the thorium spectrum.", "doi": "10.7907/DEEP-WY61", "publication_date": "1951", "thesis_type": "phd", "thesis_year": "1951" }, { "id": "thesis:10523", "collection": "thesis", "collection_id": "10523", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:10172017-084702172", "primary_object_url": { "basename": "Felt_GL_1951.pdf", "content": "final", "filesize": 31099922, "license": "other", "mime_type": "application/pdf", "url": "/10523/1/Felt_GL_1951.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "A Measurement of the Value of h/e by the Determination of the Short Wavelength Limit of the Continuous X-Ray Spectrum at 25 Kilovolts", "author": [ { "family_name": "Felt", "given_name": "Gaelen Lee", "clpid": "Felt-Gaelen-Lee" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "The apparatus used in the experiment is described in detail\r\nand the calibration of the instruments is discussed.\r\nThe procedure followed in the experiment is described.\r\nExperimental results are presented in the form of curves and the \r\nanalysis of the curves is given in detail. The final value of \r\nthe ratio h/e obtained in this experiment is
\r\n\r\n\r\nh/e = 1.37912 \u00b1 0.00007 x 10-17erg-sec/esu
", "doi": "10.7907/H0QJ-YJ54", "publication_date": "1951", "thesis_type": "phd", "thesis_year": "1951" }, { "id": "thesis:17574", "collection": "thesis", "collection_id": "17574", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:07302025-174745486", "primary_object_url": { "basename": "West_WJ_1949.pdf", "content": "final", "filesize": 35525959, "license": "other", "mime_type": "application/pdf", "url": "/17574/1/West_WJ_1949.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "A Precision Study of the Molybdenum and Tungsten K\u03b1\u2081 X-Ray Lines, and a Measurement of the Reflecting Properties of the (310) Planes of Quartz, by the Method of the Two Crystal X-Ray Spectrometer", "author": [ { "family_name": "West", "given_name": "William Junius", "clpid": "West-William-Junius" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "Using a precision two crystal x-ray spectrometer, the K\u03b11 lines of\r\nmolybdenum and tungsten and the (310) planes of quartz were studied\r\nprimarily for the purpose of calibrating the curved crystal gamma ray\r\nspectrometer, designed and built by J. W. M. DuMond, so as to help provide\r\na precision linkage between the gamma and x-ray regions. Absolute\r\ndeterminations of the Bragg angles for \u03b11 and WK\u03b11 reflected from the\r\n(310) planes of quartz are described. These were undertaken (1) to\r\nstandardize the tungsten K spectrum with higher accuracy in terms of the\r\nSiegbahn x-ray scale of wavelengths, and (2) to yield on this scale a \r\nprecision determination of the grating constant of the quartz (310) planes.\r\nThe wavelength for the WK\u03b11 line was found to be
\r\n\r\n\u03bbK\u03b11 = 208.575 \u00b1 0.008 x.u. (Siegbahn scale)
\r\n\r\nThe grating constant of the quartz (310) planes was determined as
\r\n\r\nd18\u00b0 = 1177.637 \u00b1 0.020 x.u. (Siegbahn scale)
\r\n\r\nThe reflecting properties of the (310) planes of quartz in the\r\nunstressed condition were measured experimentally in the wavelength\r\nrange 0.123\u00c5 \u2264 \u03bb \u2264 0.710\u00c5 and a comparison made to the results calculated\r\nfrom the theoretical diffraction patterns for the particular quartz crystals\r\nused. It was found that the integrated reflecting power did not decrease\r\nwith the first power of the wavelength (as predicted by theory), but to a\r\npower slightly less than unity. This result differs from the work of\r\nDavid A. Lind who found that the integrated reflecting power decreased as\r\n\u03bb2 for an identical quartz plate to the ones used here, but in the\r\nstressed condition as found in the curved crystal spectrometer
\r\n\r\nThe development of a xenon filled Geiger counter is presented. This\r\ncounter was used as a highly efficient detector of the x-rays.
", "doi": "10.7907/p5v7-wn41", "publication_date": "1949", "thesis_type": "phd", "thesis_year": "1949" }, { "id": "thesis:17317", "collection": "thesis", "collection_id": "17317", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:05302025-213209046", "primary_object_url": { "basename": "Lind_DA_1948.pdf", "content": "final", "filesize": 33021078, "license": "other", "mime_type": "application/pdf", "url": "/17317/1/Lind_DA_1948.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "Precision Spectroscopy of X and Gamma Radiation Using the Focusing Crystal Principle. A Determination of the Luminosity in the Wavelength Range 10 to 500 X.U. and a Preliminary Measurement of Gamma Radiation from Au\u00b9\u2079\u2078", "author": [ { "family_name": "Lind", "given_name": "David Arthur", "clpid": "Lind-David-Arthur" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "The principles of the curved crystal transmission type\r\nspectrometer are discussed with an analysis of the constructional\r\ntolerances which are necessary for spectroscopy of\r\nx-rays and gamma radiation to 1.7 Mev. energy. A description\r\nof the spectrometer which was completed and put into operation\r\nis given. The spectrometer has a two-meter focal distance\r\nwith a dispersion of one mm. per X. U. at the sine screw and\r\nhas a constant resolution equal to 0.1 X. U. The (310) planes\r\nof a quartz plate one mm. thick are used in the transmission\r\narrangement. The wave-length range is from 7 X. U. to 500\r\nX. U. with a precision of 0.01 X. U. The theoretical results\r\nof the diffraction theory in ideal and real crystals are\r\nsummarized. Using these results the absolute intensity in\r\nthe diffracted beam (luminosity function) is calculated as\r\na function of wave-length under certain simplifying assumptions.\r\nAn experimental determination of the luminosity\r\nfunction between 500 X. U. and 11 X. U. was made; the integrated\r\nreflection coefficient was found to be a function\r\nof \u03bb2 between these limits. These data indicate that a\r\nquartz crystal under an inhomogeneous stress behaves as\r\nwould a mosaic crystal. A comparison of the reflection\r\ncoefficients with theoretical values shows good agreement.\r\nAt 0.4 Mev. only 0.3% of the incident quanta are diffracted\r\nby the crystal. Sources of 50 mc. or greater are needed\r\nsince at present only one quantum in 108 will register in\r\na spectral line. A precision determination of one gamma-ray\r\nline in the radio-gold Au198 spectrum was made with the\r\nresult
\r\n\r\nE = 0.4112 \u00b1 0.0002 Mev.
\r\n\r\nThis represents the first precision determination of any\r\ngamma radiation energy. Finally, design requirements and\r\nlimitations of the focusing crystal method are discussed\r\nto indicate the range of usefulness and the results which\r\nmay be obtained with such an instrument.
", "doi": "10.7907/yfjh-gj31", "publication_date": "1948", "thesis_type": "phd", "thesis_year": "1948" }, { "id": "thesis:16984", "collection": "thesis", "collection_id": "16984", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:02032025-213058172", "primary_object_url": { "basename": "Bailey_HH_1941.pdf", "content": "final", "filesize": 21044157, "license": "other", "mime_type": "application/pdf", "url": "/16984/1/Bailey_HH_1941.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "A Study of the Short Wave-Length Limit of the Continuous X-Ray Spectrum", "author": [ { "family_name": "Bailey", "given_name": "Howland Haskell", "clpid": "Bailey-Howland-Haskell" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "Because of the troublesome discrepancy among the natural atomic\r\nconstants e, h and mo which has existed since 1935, a precision \r\nmeasurement of h/e by the short wave-length limit of the continuous x-ray spectrum\r\nis undertaken. The method used is the customary one of observing\r\nan isochromat, but several changes over previous practice are made in\r\nthe apparatus and the experimental technique, and these are described\r\nin detail. Chief among these are: (a) an improved filament supply circuit\r\nand an electronic robot for stabilizing the voltage, (b) an elaborately\r\ncalibrated precision resistance for measuring the voltage, (c)\r\nimproved sensitivity in the ion chamber measurements of intensity, (d)\r\nthe use of freshly cleaved crystals in the two-crystal monochromator to\r\nimprove its resolving power and thereby reduce the fillet at the foot of\r\nthe isochromat (made possible with the high intensity available from the\r\nWatters Memorial power supply and x-ray tube), (e) the use of Ross balanced\r\nfilters to suppress the effect of non-coherently scattered radiation\r\nand to eliminate the integrated effect of the wings of the spectral\r\ntransmission \"window\" of the monochromator, (f) an indirect cathode to\r\npreclude the existence of excess energy secondary electrons, and (g) a\r\nvery clean target of high atomic number to insure a good intercept on\r\nthe isochromat. The calibration of the voltmeter and of the spectrometer\r\nare not yet in a satisfactory state, but preliminary results give h/e=\r\n(1.38054 \u00b1 .00115) x 10-17 erg sec/esu. This is to be compared with the\r\nindirect value (obtained from combining the Rydberg constant, the x-ray\r\nvalue of e and the best value of e/mo ) of (1.37929 \u00b1 .00023) x 10-17 erg\r\nsec/esu. The overlapping of these probable errors demonstrates the \r\nresolution of the discrepancy. The experiment is quite capable of five times\r\nthe stated precision after certain checks are made, and better results\r\nare expected soon.", "doi": "10.7907/dw87-7z48", "publication_date": "1941", "thesis_type": "phd", "thesis_year": "1941" }, { "id": "thesis:16960", "collection": "thesis", "collection_id": "16960", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:01272025-223541303", "primary_object_url": { "basename": "Miller_PH_1940.pdf", "content": "final", "filesize": 14988445, "license": "other", "mime_type": "application/pdf", "url": "/16960/1/Miller_PH_1940.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "An Investigation of the Validity of X-Ray Crystal Method of Determining N and e", "author": [ { "family_name": "Miller", "given_name": "Park Hays, Jr.", "clpid": "Miller-Park-Hays-Jr." } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "No abstract.", "doi": "10.7907/a0h7-tk08", "publication_date": "1940", "thesis_type": "phd", "thesis_year": "1940" }, { "id": "thesis:16799", "collection": "thesis", "collection_id": "16799", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:10162024-213147638", "primary_object_url": { "basename": "Bollman_VL_1936.pdf", "content": "final", "filesize": 15609724, "license": "other", "mime_type": "application/pdf", "url": "/16799/1/Bollman_VL_1936.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "Tests of the Validity of the X-Ray Crystal Method for Determining \"e\"", "author": [ { "family_name": "Bollman", "given_name": "Vernon Leroy", "clpid": "Bollman-Vernon-Leroy" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "To establish the validity of the x-ray crystal method for\r\ndetermining \"e\", the density of microscopic powdered calcite and the\r\nx-ray diffraction angles for several sets of planes of a sample of\r\nthe same powdered calcite were measured.
\r\n\r\nThe density of powdered calcite was determined pycnometrically to be
\r\n\r\n\u03c1 = 2.71022 \u00b1 0.00035 gms/cc
\r\n\r\nin agreement with macroscopic calcite.
\r\n\r\nX-ray diffraction rings of the Ni K\u03b1, and K\u03b12 lines for\r\nplanes (330), (677), (233) and (163) (crystallographic system of axes)\r\nwere observed using a Seeman-Bohlin powder camera. The observed rings\r\nall occur at diffraction angles near 90\u00b0 thus affording extremely high\r\nprecision in the lattice constant determinations. The parameters \r\nfound for powdered calcite from these data are
\r\n\r\nC = 12.8197 \u00b1 0.0016 A (Siegbahn Scale)
\r\n\r\nand \u03b2 = 101 54' 18\" \u00b1 48\".
\r\n\r\nThe grating space of the cleavage planes calculated from these\r\ndata is
\r\n\r\nd100 = 3.0282 A (Siegbahn Scale of wavelengths)
\r\n\r\nin agreement with d100 for macroscopic calcite within the experimental\r\nerror of 0.05 percent.
\r\n\r\nFrom the known grating wavelength of Cu K\u03b1, and the \r\nexperimental data for powdered calcite the value
\r\n\r\ne = 4.799 \u00b1 0.007 x 10-10 e.s.u.
\r\n\r\nwas obtained.
\r\n\r\nThis measurement constitutes the first high precision lattice\r\ndetermination on calcite ever made by the powder method. It is free\r\nfrom the objection frequently raised in the case of determinations on \r\nlarge calcite crystals that the density determination may not be\r\nrepresentative of the thin layer at the surface of a crystal involved\r\nin x-ray reflection.
", "doi": "10.7907/644d-vg91", "publication_date": "1936", "thesis_type": "phd", "thesis_year": "1936" }, { "id": "thesis:16803", "collection": "thesis", "collection_id": "16803", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:10212024-180539496", "primary_object_url": { "basename": "Watson_BB_1935.pdf", "content": "final", "filesize": 12057873, "license": "other", "mime_type": "application/pdf", "url": "/16803/1/Watson_BB_1935.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "The Development of the Curved Quartz Crystal X-Ray Spectograph and a Determination of the Grating Constant of Quartz", "author": [ { "family_name": "Watson", "given_name": "Bernard Bennett", "clpid": "Watson-Bernard-Bennett" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "The development of the curved. crystal type.\r\nof high luminosity x-ray spectrograph is traced from\r\nthe original suggestion by Gouy in 1916 through the\r\nwork of Cauchois in 1932 and 1933. The construction\r\nof a small experimental spectrograph of the curved\r\ncrystal type is described. The use of quartz instead\r\nof mica or gypsum which are customarily used and the\r\nimprovement of the spectra obtained when quartz is\r\nused are discussed.
\r\n\r\nThe theory of the curved crystal spectrograph \r\nhas been extended in two ways - (1) to cover\r\nthe doubling of spectral lines which arises due to\r\nreflections from opposite surfaces of the crystal\r\nand (2) to cover the vertical separation of spectral\r\nlines reflected from opposite sides of atomic\r\nreflecting planes. This last effect is traced to\r\na non-parallelism between the reflecting planes\r\nand the axis of curvature of the crystal.
\r\n\r\nBy means of the curved crystal spectrograph\r\nthe grating constant for the basal planes of\r\nquartz was determined. This value was found to be
\r\n\r\nd = 5.393 \u00b1 .002 \u00c5
", "doi": "10.7907/p0f8-cp78", "publication_date": "1935", "thesis_type": "phd", "thesis_year": "1935" }, { "id": "thesis:16832", "collection": "thesis", "collection_id": "16832", "cite_using_url": "https://resolver.caltech.edu/CaltechTHESIS:11032024-085514466", "primary_object_url": { "basename": "Brown_VA_1935.pdf", "content": "final", "filesize": 37741955, "license": "other", "mime_type": "application/pdf", "url": "/16832/1/Brown_VA_1935.pdf", "version": "v2.0.0" }, "type": "thesis", "title": "A Precision Comparison of Laue and Bragg Reflection with the Double Crystal Spectrometer and the Photographic Spectrometer", "author": [ { "family_name": "Brown", "given_name": "Vinton Austin", "clpid": "Brown-Vinton-Austin" } ], "thesis_advisor": [ { "family_name": "DuMond", "given_name": "Jesse William Monroe", "clpid": "DuMond-J-W-M" } ], "thesis_committee": [ { "family_name": "Unknown", "given_name": "Unknown" } ], "local_group": [ { "literal": "div_pma" } ], "abstract": "No abstract.", "doi": "10.7907/65nh-j867", "publication_date": "1935", "thesis_type": "phd", "thesis_year": "1935" } ]