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Differential Cross Section For Charged A₁ Photoproduction Using The Regge Exchange Formalism, Keiji Kikkawa, Barbara N. Hale

Physics Faculty Research & Creative Works

The Regge-pole formalism is applied to the calculation of the differential cross section for A₁⁺ photo-production in the region |t_min| < -t < 10µ². The p, A₁, A₁-daughter, A₂, and π trajectory contributions are considered, and use is made of chiral dynamics to estimate the unknown coupling constants. We find that the π and the A₂ trajectories provide the dominant contributions.

Proposed Thermodynamic Pressure Scale For An Absolute High-Pressure Calibration, Daniel L. Decker, J. Dean Barnett

Faculty Publications

The field of high pressure has developed rapidly over the past few years to a point where relatively sophisticated experiments are being attempted. In many experiments it is no longer sufficient to qualitatively estimate the pressure or to base conclusions on experimental results tied to an empirical pressure parameter. One desires to accurately know the pressure dependence of physical quantities related to a true thermodynamic scale.

Projected Hartree Product Wavefunctions. V. Density Matrices And Operators Containing Spin, Gordon A. Gallup

Gordon Gallup Publications

Formulas are given to allow the calculation of the various spin components of the first-order density and transition density matrices from one spatial component of a pure spin-state wavefunction and certain reduced operators. Similar expressions are given for the second-order density for singlet and doublet systems. These results are useful for the calculation of matrix elements of operators containing the spin. ©1970 American Institute of Physics

Projected Hartree Product Wavefunctions. Iv. Radial Correlation In Some Three- And Four-Electron Atoms, L.G. Heikes, Gordon A. Gallup

Gordon Gallup Publications

The energies of some three- and four-electron atoms including radial correlation have been determined by a spin-free version of the projected Hartree–Fock method. The wavefunction possesses the maximum flexibility allowable under the general restrictions of the method, and it is shown that this flexibility is necessary to adequately account for the differences between intra- and intershell correlation. Some comments on the AMO method are included. ©1970 American Institute of Physics

Measurement Of Cyclohexane Ultrasonic Velocity Using Photon-Phonon Scattering Interactions, Edward W. Taylor Jr.

Physics & Astronomy ETDs

The construction of a frequency modulated optic cell and its operation for studying the ultrasonic velocities of cyclohexane, acetone and ethyl alcohol as a function of temperature is described. A description of photon-phonon scattering interactions is presented. The appearance of the intensity distribution of the scattered light is treated, and an analysis of the experimental results is included. The special scattering case of Bragg diffraction of coherent light was used for determining the ultrasonic velocities of cyclohexane as a function of temperature. Ramifications of the Raman-Nath and Bragg diffraction effects are discussed. The relationship v_T = 1376.78 - 5.25 …

On The Relation Between Hard-Core And Velocity-Dependent Potentials: An Application To The Photonuclear Sum Rules, Paul Finkler, H. S. Valk

Paul Finkler Papers

A canonical transformation relating hard-core and velocity-dependent nucleonnucleon potentials is applied to the Srivastava potential and an equivalent hard-core potential is found. It is shown that the deuteron photonuclear electric-dipole integrated and bremsstrahlung-weighted cross sections resulting from the two equivalent potentials are essentially the same. The reasons for this agreement suggest that differences between the two sets of cross sections may remain small in other nuclei employing this type of potential.

Response Of Nuclear Emulsion To Electron Beams, Robert Katz, E. J. Kobetich

Robert Katz Publications

A recent theory of particle tracks assumes that the probability P for grain development in nuclear emulsion depends on the local dose E of ionization energy deposited by secondary electrons (delta rays) in the neighborhood of the particle track. The response is assumed to be one of exponential survival; that is, if E₀ is the dose for 37% survival, then P = 1 – exp (-E/E₀). By calculation of the dose E(t) deposited at depth t in the emulsion by normally incident, monoenergetic electron beams, and applying the assumed dose-effect relationship, …

Rbe, Let, And Z/ΒΑ, Robert Katz

Robert Katz Publications

A call has been issued by Turner and Hollister in this journal for nomination of a suitable combination of charge and velocity to replace LET. It is the purpose of this communication to point out that no single combination of these variables can fully characterize track effects, as these are affected by the ratio of the range r_m of the delta ray of maximum energy to the radius a₀ of the sensitive volume.

Electrical Conductivity In Nh4Cl And Nd4Cl Single Crystals, Robert Fuller, F.W. Patten

Robert G. Fuller Publications

Electrical conductivity measurements are reported for normal and deuterated ammonium chloride single crystals in the temperature regions which characterize the pure and the impurity-dominated materials. We conclude from the data that conductivity in ammonium chloride is due to the formation of either cation or anion vacancies and a subsequent process controlled by a proton transfer. Our results are found to be consistent with a model proposed by Herrington and Staveley.

Formation Of Particle Tracks, Robert Katz, E. J. Kobetich

Robert Katz Publications

The formation of particle tracks, and such phenomena as the detection of charged particles and the damage produced by charged particles, are intimately related to the spatial distribution of ionization energy deposited by δ-rays. Changes in the spectrum of δ-rays with the velocity of the primary particle imply that linear measures of the interaction of the primary particle with the medium, such as specific energy loss, or primary ionization, are unsatisfactory measures of effects produced in the medium, for they contain no knowledge of the spatial deposition of the lost energy.

Energy-Loss Spectra And Collision Cross Sections For Impact Of 20-120-Kev Positive Ions On Molecular Nitrogen, F. D. Schowengerdt, John T. Park

Physics Faculty Research & Creative Works

Inelastic energy-loss spectra induced by impact of H+, H2+, and Ar+ on N2 have been measured at incident ion energies of 20-120 keV, with an energy resolution of about 2 eV. Prominent peaks are observed at energy losses of 9.5 and 13.8 eV. The first of these is well resolved and is attributed to excitation of the Lyman-Birge-Hopfield (LBH) system of N2. The peak at 13.8 eV is believed due primarily to excitation of the bu1 band of the Worley-Jenkins series. The locations of these features on the energy-loss scale do not agree with results of the electron impact work …

Theory Of Droplet Growth In Clouds. I. The Transient Stage Of The Boundary-Coupled Simultaneous Heat And Mass Transport In Cloud Formation, John C. Carstens, Joseph T. Zung

Physics Faculty Research & Creative Works

Two solutions to the system of equations describing the simultaneous heat and mass transport involved in the condensational growth of a droplet in a supersaturated atmosphere are presented. The first, valid for very short times, describes the transient stage of such growth; the second, valid for longer times, presupposes the establishment of a steady-state condition. The two are shown to be complementary for the cases examined. The equations examined satisfy the usual boundary conditions imposed on a drop in a concentric sphere as required by the cellular model for cloud formation. Hence our results can be immediately extended to the …

Optical Phenomena In Diatoms, Richard B. Hoover, Miriam J. Hoover

Journal of the Arkansas Academy of Science

Diatoms are unicellular algae which fabricate siliceous shells that are frequently marked with intricate ornamentations and patterns. The nature and characteristics of the siliceous shells provide a basis for diatom taxonomy and give rise to a number of interesting and colorful optical phenomena. This paper presents the results of investigations of diffraction phenomena, complementary color behavior, Rayleigh scattering and optical activity in diatoms.

Note On "Approximate Free Energies For Heisenberg Ferromagnets", J. H. Hemmann, Harry A. Brown

Physics Faculty Research & Creative Works

No abstract provided.

Measurements Of Excited-State Population Ratios Of Atomic Hydrogen Produced By Charge-Exchange Neutralization Of Energetic Proton Beams, Robert H. Mcfarland, Archer H. Futch

Physics Faculty Research & Creative Works

Excited-state population ratios for atomic hydrogen have been measured for energetic hydrogen ions neutralized by charge exchange with a number of different metallic vapors and permanent gases. Electric field ionization techniques were used to determine excitation ratios. Detection of the energetic ions and neutrals was accomplished using partially depleted surface-barrier detectors. Counting, using phase-detection techniques in which an add-subtract scaler was phased to the signal, provided an improved signal-to-noise ratio. Two methods were used to provide desired targets. Metallic vapor and permanent-gas thin targets of the order of 10-5 mTorr cm were produced as chopped neutral beams, using conventional crossed-beam …

Ground-State Wave Function Of Shallow Donors In Uniaxially Stressed Silicon: Piezohyperfine Constants Determined By Electron-Nuclear Double Resonance, Edward B. (Boyd) Hale, Theodore G. Castner

Physics Faculty Research & Creative Works

Stress-induced changes in the ENDOR spectra of a shallow donor electron interacting with various Si29 nuclei neighboring the donor have been experimentally and theoretically investigated. For each of the three measured donors - As, P, and Sb - the compressional, uniaxial stress was applied along the [001] axis and its magnitude corresponded to strains up to 10-3. To describe the observed linear and quadratic shifts and splitting's of the lines in an ENDOR shell, we have defined a set of piezo hyperfine constants. One piezo hyperfine constant was measured for each axis-class shell; three independent piezo hyperfine constants were measured …

(02) The Papers Of Robert H. Goddard, Volume I: [1927 And 1933: Material For An Autobiography], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section contains material for an autobiography written by Robert Goddard in 1927 with interpolations in 1933.

Disclaimer: The images in these scans have been rendered somewhat distorted after the fact. We apologize for this error. Thankfully, most of the photographs used in these …

(06) The Papers Of Robert H. Goddard, Volume I: 1898-1924 [1921-1924: Beginnings Of Experimentation With Liquid Propellants], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers Robert Goddard's life from 1921 through 1924. During this time, Goddard began his experimentation with liquid propellants for rockets, became a part-time consultant on solid-propellant rocket weapons for the U.S government, began a twenty-year tenure as Director of Physical Laboratories at …

(04) The Papers Of Robert H. Goddard, Volume I: 1898-1924 [1898-1914: Speculation And Preparation], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers Robert Goddard's life from age sixteen through thirty-two. It contains diary entries, correspondence, school themes, entries from his green notebooks (used for calculations), a graduation oration, published articles,

This section contains the following articles:
"The Use of the Gyroscope in the Balancing and …

(03) The Papers Of Robert H. Goddard, Volume I: 1898-1924 [1921: Autobiographical Statement], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section is a brief Autobiographical Statement written by Robert Goddard in 1921. It was presumed to have been written for the Inventors Bulletin, but it is now known whether the statement was ever published.

Disclaimer: The images in these scans have been rendered …

(10) The Papers Of Robert H. Goddard, Volume Ii: 1925-1937 [1932-1934: Interlude At Clark University], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers a brief period in Robert Goddard's life, from mid 1932 to mid 1934, between his two grant funded periods (1930-1932, 1934-1942) for rocket research in Roswell, New Mexico. During this time, he continued to teach at Clark University and conduct research …

(09) The Papers Of Robert H. Goddard, Volume Ii: 1925-1937 [1930-1932: The First New Mexico Adventure], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers Robert Goddard's life from mid 1930 to mid 1932 when Goddard received his first Guggenheim grant (this one from Daniel) which would bring Robert and Esther to Roswell, New Mexico for two years of rocket research. They would soon relocate to …

(13) The Papers Of Robert H. Goddard, Volume Iii: 1938-1945 [1938-1941: Rockets With Turbopumps], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers 1938 to 1942. During this period, Goddard begins to develop turbine-driven pumps for liquid propellant rockets and conducts a series of flight tests with pump-driven rockets.

This section contains correspondence by, to, and about Robert H. Goddard from the following people and entities: …

(05) The Papers Of Robert H. Goddard, Volume I: 1898-1924 [1915-1920: Experimentation With Solid Propellants], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers Robert Goddard's life from 1915 through 1920. During this time, he became an Assistant Professor in Physics at Clark University, demonstrated that reaction takes place in a vacuum, hence a rocket could function in airless space, received his first Smithsonian grant …

(08) The Papers Of Robert H. Goddard, Volume Ii: 1925-1937 [1925-1930: Liquid-Propellant Rockets Fly], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers Robert Goddard's life from 1925 through the middle of 1930. During this time, Goddard achieved his greatest success on March 16, 1926, with the first ever flight of a liquid-propellant rocket. This period also saw a 1929 flight that attracted a …

(01) The Papers Of Robert H. Goddard, Volume 1: 1898-1924 [Forward, Introduction], Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section contains a forward by G. Edward Pendray and an introduction by Esther C. Goddard.

Disclaimer: The images in these scans have been rendered somewhat distorted after the fact. We apologize for this error. Thankfully, most of the photographs used in these papers …

(14) The Papers Of Robert H. Goddard, Volume Iii: 1938-1945 [1941-1945: Jato And Variable Thrust For The Military], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers the final years of Robert Goddard's life, from 1941 to 1945. During this time, he became the Director of Research for the Bureau of Aeronautics, Navy Department, at Annapolis, Maryland, developing variable-thrust rocket motor later used on Bell X-2 rocket plane. He also …

(11) The Papers Of Robert H. Goddard, Volume Ii: 1925-1937 [1934-1937: Return To New Mexico; Pressure-Tank Rockets], Robert H. Goddard, Esther C. Goddard, G. Edward Pendray

The Papers of Robert H. Goddard

Meticulously curated and edited by Esther C. Goddard and G. Edward Pendray, The Papers of Robert H. Goddard is a 1700-page 3 volume set published in 1970. The set presents a careful and exhaustive chronological presentation of Robert Goddard’s life through diary snippets, notebook entries, correspondence, publications, speeches, patent outlines, school papers, press, reports and more.

This section covers Robert Goddard's life from mid-1934 through 1937. During this time, Robert and Esther Goddard began their second stint in Roswell, New Mexico for Guggenheim funded rocket research (the first was 1930 to 1932). This one would last from 1934 to 1942. …

On The Physical Properties Associated With Omega Phase In Titanium-Chromium Alloys, Serag El Din El Sayed Habib

Archived Theses and Dissertations

No abstract provided.

Shell Source Burning Stars With Highly Condensed Cores, S. Refsdal, A. Weigert

Department of Physics and Astronomy: Faculty Publications

Simple analytical relations are derived - similar to the homology relations for homogeneous stam - which describe the behaviour of shell source burning models with highly condensed cores. Many features which are known from evolutionary calculations (and partly &om observations) of such stars can be understood as coming essentially from the increase of the mass M₆ of the core.