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Nonperturbative Proof Of The Non-Abelian Anomalies, A. P. Balachandran, G. Marmo, V. P. Nair, C. G. Trahern

Publications and Research

We give a nonperturbative derivation of non-Abelian anomalies.

Theoretical And Experimental Optical Holography, Warren A. Krueger

Senior Scholar Papers

The intent of this paper is to present an analysis of optical holography. Both the physical theory behind holography and the experimental techniques used in making holograms will be presented. To accomplish this goal, the paper is divided into two independent sections: the theoretical section followed by the experimental section. Each section is intended to be a complete unit. The Theoretical Section is an exposure to the theory behind holography. This consists of a review of the concepts of interference and diffraction. followed by a brief review of partial coherence. The remaining part of the Theoretical Section is devoted to …

Massless Neutrinos And The Stellar Stopping Power Via The V-A And Weinberg Interactions, P.T. Leung, M. L. Rustgi

Physics Faculty Publications and Presentations

A formula for the stopping power of matter for neutrinos and antineutrinos, interacting with electrons via the weak interaction in the context of both the V-A theory and the Weinberg theory is derived in the high-Q approximation and applied to study the solar-neutrino anomaly. The result shows that neutrinos extending in energy from 1 to 10 MeV produced inside the Sun escape it essentially without any loss of energy. In agreement with previous investigators, Rustgi, Leung, Turner, and Brandt (1981). It is found that the neutrinos should retain the energy given them at their creation essentially forever and permeate the …

On The Transport Equations For Anisotropic Plasmas, Abdallah R. Barakat

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

First, I attempt to present a unified approach to the study of transport phenomena in multicoponent anisotropic space plasmas. In the limit of small temperature anisotropies this system of generalized transport equations reduces to Grad's 13-moment system of transport equations. In the collisionless limit, the generalized transport equations account for collisionless heat flow, collisionless viscosity, and large temperature anisotropies. Also, I show that with the appropriate assumptions, the system of generalized transport equations reduces to all of the other major systems of transport equations for anisotropic plasmas that have been derived to date.

Next, for application to aeronomy and space …

Brewster And Pseudo-Brewster Angles Of Uniaxial Crystal Surfaces And Their Use For Determination Of Optical Properties, M. Elshazly-Zaghloul, R. M.A. Azzam

Electrical Engineering Faculty Publications

Brewster and pseudo-Brewster angles are defined for surfaces of transparent and absorbing uniaxial crystals parallel and perpendicular to the optic axis. Two Brewster angles of a transparent uniaxial crystal surface parallel to the optic axis, measured when the optic axis is oriented perpendicular and parallel to the plane of incidence, readily determine the ordinary and extraordinary indices N_o and N_e. N_o and N_e can also be obtained from two Brewster angles measured on a surface perpendicular to the optic axis in contact with two media of different refractive indices. Conditions for the existence of two …

Simple Vibrating Sample Magnetometer, J.A. Gerber, W.L. Burmester, David J. Sellmyer

David Sellmyer Publications

Design features of a simple and relatively inexpensive homemade vibrating sample magnetometer are described. These include signal electronics which employs an analog divider rather than the usual electromechanical feedback circuit, and a method for gas cleaning during sample changes allowing long experiments at liquid helium temperatures in a superconducting solenoid. Review of Scientific Instruments is copyrighted by The American Institute of Physics.

Reaction ⁶Li(P, Δ⁺⁺)⁶He At 1.04 Gev And The Δ−N Interaction, T. Hennino, D. Bachelier, Oleksa-Myron Bilaniuk, J. L. Boyard, J. C. Jourdain, M. Roy-Stephen, P. Radvanyi, M. Bedjidian, E. Descroix, P. Foessel, S. Gardien, J. Y. Grossiord, A. Guichard, M. Gusakow, R. Haroutunian, M. Jacquin, J. R. Pizzi, A. Garin

Physics & Astronomy Faculty Works

The reaction ⁶Li(p, Δ⁺⁺)⁶He has been studied at 1.04 GeV for transferred momenta ranging from 0.11 to 0.35 (GeV/c)2. An exponential decrease of the cross section is observed. A Glauber-type calculation is presented. The possibility of extracting information on σ(ΔN) and α(ΔN) is discussed.

Book Review: The Theory Of Atomic Structure And Spectra By Robert D. Cowan, Anthony F. Starace

Anthony F. Starace Publications

The field of atomic spectroscopy is currently experiencing a resurgence of interest owing on the one hand to its applications in astrophysics, plasma physics, and other fields and on the other hand to the development of new experimental tools to probe atomic structures. One example of the latter is the use of tunable lasers to study highly excited atoms in the presence of strong external electric and magnetic fields. Another is the use of synchrotron radiation to probe with increasing detail the inner shell structure of rare earth, actinide, and other heavy atoms.

Photoelectron Angular Distributions: Energy Dependence For S Subshells, Steven T. Manson, Anthony F. Starace

Anthony F. Starace Publications

An overview of the theory of photoelectron angular distributions for atoms is presented. Its features, which are embodied in a single asymmetry parameter β in the electric dipole approximation, are examined within the framework of the angular momentum transfer formulation. The β parameter is in principle always energy dependent. Within the LS coupling approximation, however, there are instances, each representing a multitude of particular photoionization processes, in which β is an analytically determined constant. The energy dependence of the β parameters in such instances is due entirely to spin-orbit and other relativistic interactions. The study of the energy dependence of …

Random-Phase Approximation To One-Body Transition Matrix Elements For Open-Shell Atoms, Anthony F. Starace, Siamak Shahabi

Anthony F. Starace Publications

A graphical procedure is presented for evaluating each term in the equation satisfied by the first-order transition matrix for an arbitrary (open-shell) atom. For those terms involving the interaction of excited virtual pairs of electrons with the ionic core, we introduce the approximation that there is no exchange of orbital or spin angular momentum with the ionic core. This approximation is shown to lead to the random-phase approximation (RPA) equations in the closed-shell-atom case; we use it to define the RPA for open-shell atoms. The single equation satisfied by the first-order transition matrix is used to obtain a set of …

Four-Color And Hβ Photometry Of The Galactic Cluster M25, Edward G. Schmidt

Edward Schmidt Publications

Four-color and Hβ photometry has been obtained for 39 stars in the field of the galactic cluster M25. The membership of the individual stars is discussed. From 27 stars which are considered likely members we obtain a mean distance modulus of 8.76 and a mean color excess of E(b – y) = 0.341.

Intermediate-Band Photometry Of The Open Cluster Ngc 3114, Edward G. Schmidt

Edward Schmidt Publications

Four-color and Hβ photometry has been obtained of 33 stars in the southern galactic cluster NGC 3114. This cluster contains many interesting stars including blue stragglers, red giants, and stars with spectral peculiarities. The distance modulus was found to be V₀ – M_v = 10.26 which corresponds to 1130 pc. The color excess is E(b – y) = 0^m.060. The cluster appears to be slightly older than the Pleiades. There are two extreme blue stragglers and six additional stars which might be considered milder cases of the same phenomenon. The distance moduli of …

Fe Hyperfine Fields In Fe3-XVXSi Alloys, T. J. Burch, C. A. Weiler, K. Raj, J. I. Budnick, V. Niculescu, G. C. Papaefthymiou, Richard B. Frankel

Physics

The Mössbauer spectra of Fe in Fe_3-xV_xSi alloys for 0≤x≤1 shows that V occupies almost exclusively one of two Fe sites (the B site). As x increases the spectra of Fe on the other site (the A, C site) becomes increasingly complex as the number of their V 1st neighbors increases. Simulated Mössbauer spectra were calculated using moments obtained by a simple model from bulk magnetization and V NMR data. This model assumes a decrease in Fe(A, C) moments as the number of their Fe 1st neighbors decreases. Comparison of the Fe(B) field of the alloy …

Giant Coercivities And Chemical Short-Range Order In Pr-Ga-Fe Metallic Glasses, S.G. Cornelison, David J. Sellmyer, J.G. Zhao, Z.D. Chen

David Sellmyer Publications

Results of magnetic, Mössbauer, and structural studies are presented for (Pr₈₀Ga₂₀)_100-xFex metallic glasses, where 0≤x≤30. For x≥20 two magnetic transitions are observed and the structural studies indicate the presence of a phase separation into at least two glassy phases, one being Fe-rich and the other Fe-deficient. Coercivities above 60 kOe are observed and the results are discussed in terms of a model involving the magnetic properties of the two phases. Journal of Applied Physics is copyrighted by The American Institute of Physics.

Are Vpd3 And Nbpd3 Itinerant Ferromagnets?, W. L. Burmester, David J. Sellmyer

David Sellmyer Publications

Low-field magnetic susceptibility and high-field magnetization results are reported for polycrystalline samples of NbPd₃, VPd₃, and iron doped VPd₃. Recent self-consistent, spin-polarized band calculations have predicted that the pure compounds are itinerant ferromagnets. Down to 1.6 K there is no evidence for either magnetic ordering or exchange enhancement in VPd₃ and NbPd₃. The Fe-doped alloys exhibit transitions at low temperatures to a magnetic cluster-glass state.

Light Scattering Determination Of Magnetic Moments Of Magnetotactic Bacteria (Invited), Charles Rosenblatt, F. F. Torres De Araujo, Richard B. Frankel

Physics

Light scattering is used to determine the average lengths and magnetic moments of magnetotactic bacteria in culture. The results are consistent with estimates made from electron micrographs.

Comparison Of Bethe's Formula For Magnetic-Moment Transitions In Atoms With The Generalized Rosenbluth's Equation, P.T. Leung, M. L. Rustgi, J. E. Turner

Physics Faculty Publications and Presentations

An error in an old but often quoted paper by Bethe (1935) on the cross section for an atomic transition caused by the magnetic moment of the projectile is corrected by comparing it with the generalized Rosenbluth's formula (1950).

Magnetic, Mössbauer, And Resistivity Studies Of Amorphous Fe74Zr26 And Fe81Hf19 Alloys, C. L. Chien, K. M. Unruh, A. Levy, Sy_Hwang Liou, J. P. Stokes, R.J. Gambino, K. Fukamichi

Sy-Hwang Liou Publications

Amorphous metal-metal samples of Fe₇₄Zr₂₆ and Fe₈₁Hf₁₉ have been studied by bulk magnetic, Mössbauer spectroscopy and resistivity measurements. The values of T_c have been determined to be 285 K and 295 K for Fe₇₄Zr₂₆ and Fe₈₁Hf₁₉, respectively. Both the magnetic isotherms and Mössbauer measurements indicate that these samples are ferromagnetics. The isomer shifts and the quadrupole interactions are much smaller than those of amorphous Fe-metalloid systems. The P(H) are broad and extend to small H values. Negative temperature coefficients of the resistivity are observed at low …

Constant-Psi Constant-Delta Contour Maps: Applications To Ellipsometry And To Reflection-Type Optical Devices, A.-R. M. Zaghloul, R. M.A. Azzam

Electrical Engineering Faculty Publications

Constant-psi constant-delta contour maps in the reduced angle-of-incidence-film-thickness plane that are useful in ellipsometry and in design of reflection-type optical devices are discussed. As a specific example, a contour map is given for the SiO₂-Si film-substrate system at the 6328-Å He-Ne laser wavelength.

Review Of Atoms And Molecules By M. Weissbluth, Anthony F. Starace

Anthony F. Starace Publications

The advent of high-powered lasers and of dedicated synchrotron light sources and the needs of research in such areas as astrophysics and fusion have led to a resurgence of interest in atomic and molecular physics. Concurrently, there have been significant advances in atomic and molecular theory, not only in the ability to make more reliable numerical predictions but also in the detailed understanding of the dynamics of atomic and molecular collisions. The nonspecialist or beginning graduate student who must read the scientific journals to learn of these advances often finds that the requisite basic knowledge is extensive. Mitchel Weissbluth, whose …

Polarization Of Fluorescence Radiation Subsequent To Inner-Shell Photoionization: Ls-Coupling Formulas, Anthony F. Starace

Anthony F. Starace Publications

The polarization and angular distribution of fluorescence radiation subsequent to inner-shell photoionization in atoms are presented here in the important special case that dynamic amplitudes are calculated in LS coupling taking full account of anisotropic electron-ion interactions. The resulting formulas require for their evaluation no more dynamical information than is usually obtained in an LS-coupling calculation of the photoionization cross section. Exact geometrical relationships which are obscured in more general treatments become apparent in an LS-coupling formulation. Thus it is shown that in LS coupling the fluorescence resulting from photoionization of an s subshell in an atom having …

Magneto-Hall And Magnetoresistance Coefficients In Semiconductors With Mixed Conductivity, David C. Look

Physics Faculty Publications

Magneto-Hall and magnetoresistance formulas, correct to order B², are derived for the case in which both single-carrier and mixed-carrier effects are important. Also, a new magneto-Hall coefficient Is Presented: β=‹π⁴›‹π›/‹π²›³ - 1. Values of β for various scattering mechanisms are calculated and compared with experiment

The Chromospheres Of Classical Cepheids. I. Low Resolution Iue Spectra, Edward G. Schmidt, Sidney B. Parsons

Edward Schmidt Publications

We have undertaken a program to study the behavior of chromospheres in classical Cepheids using both ground-based and satellite-based observations. Five stars, δ Cep, η Aql, β Dor, ζ Gem, and l Car, have been included, and where possible the various types of data have been obtained simultaneously. The first part of this investigation concerns low dispersion spectra from the IUE satellite. Fine error sensor (FES) magnitudes are presented for the five Cepheids and, in the case of one, η Aql, are used to re-discuss the period. The "artificial viscosity dip" predicted by some theoretical calculations may be present in …

Conductance In Restricted-Dimensionality Accumulation Layers, A. B. Fowler, A. Hartstein, Richard A. Webb

Faculty Publications

Conductance has been studied in metal-oxide-silicon field-effect transistor accumulation-layer samples in which it is possible to constrict the channel to small dimensions both perpendicular to the surface and perpendicular to the channel. A temperature-dependent conductance σ=σ₀exp[-(T₀/T)ⁿ] is observed, where n=1/2 for small channel widths and n=1/3 for larger channel widths. It is believed that this behavior arises from a transition from one-dimensional to two-dimensional variable-range hopping in the sample.

Dielectric Constant In Fluids Of Classical Deformable Molecules, John D. Ramshaw

Physics Faculty Publications and Presentations

Classical statistical mechanical description of dielectric fluids is further discussed. Dipole moment correlations of polarizable molecules are discussed.

Classroom Demonstration Of Sunspots, Thomas O. Callaway, Harry D. Downing, Glen T. Clayton

Faculty Publications

No abstract provided.

Physical Science Workshop Course For Elementary Teachers, Glen T. Clayton, Harry D. Downing, Thomas O. Callaway

Faculty Publications

Science for elementary school grades K-6 varies somewhat in content from one textbook series to another, but it is fairly common that 40-60% of the material covered is directly related to physics. These texts suggest that certain learning activities such as experiments, demonstrations, and observations be carried out by the teacher and the class. Often the apparatus for a learning activity is to be constructed from simple, readily available materials. The typical elementary school teacher has had little experience in performing experiments and is often frustrated in his/her attempts at carrying out the suggested learning activity. To meet this need …

The Etc And Instantaneous Intensity, Richard C. Heyser

Unpublished Writings

Richard C. Heyser explains how to measure the energy-time response of an acoustic signal by expressing the energy density in a logarithmic form, which he cales the Energy-Time Curve (ETC).

Predicted Diurnal Variations Of Electron Density For Three High-Latitude Incoherent Scatter Radars, Jan Josef Sojka, Robert W. Schunk

All Physics Faculty Publications

We have used a high‐latitude ionospheric model to predict the diurnal variations of electron density that should be observed by the EISCAT, Chatanika and Millstone Hill incoherent scatter facilities. Our calculations were for a strong convection model without substorms. Our results provide an indication of the quantitative differences in measured electron density that are expected when the three radars probe the high‐latitude ionosphere simultaneously. The differences are significant and vary with altitude, latitude, local time, and season, and are associated with the UT dependence of the high‐latitude ionosphere which results from the displacement between the geomagnetic and geographic poles.

Observations Of The Diurnal Dependence Of The High-Latitude F Region Ion Density By Dmsp Satellites, Jan Josef Sojka, W. John Raitt, Robert W. Schunk, F. J. Rich, R. C. Sagalyn

All Physics Faculty Publications

Data from the DMSP F2 and F4 satellites for the period December 5-10, 1979, have been used to study the diurnal dependence of the high-latitude ion density at 800-km altitude. A 24-hour periodicity in the minimum orbital density (MOD) during a crossing of the high-latitude region is observed in both the winter and summer hemispheres. The phase of the variation in MOD is such that it has a minimum during the 24-hour period between 0700 and 0900 UT. Both the long term variation of the high-latitude ion density on a time scale of days, and the orbit by orbit variations …