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Interpretation of Self-Potential Anomalies Using Constitutive Relationships for Electrochemical and Thermoelectric Coupling Coefficients

Description: Constitutive relationships for electrochemical and thermoelectric cross-coupling coefficients are derived using ionic mobilities, applying a general derivative of chemical potential and employing the zero net current condition. The general derivative of chemical potential permits thermal variations which give rise to the thermoelectric effect. It also accounts for nonideal solution behavior. An equation describing electric field strength is similarly derived with the additional assumption of electrical neutrality in the fluid Planck approximation. The Planck approximation implies that self-potential (SP) is caused only by local sources and also that the electric field strength has only first order spatial variations. The derived relationships are applied to the NaCl-KCl concentration cell with predicted and measured voltages agreeing within 0.4 mV. The relationships are also applied to the Long Valley and Yellowstone geothermal systems. There is a high degree of correlation between predicted and measured SP response for both systems, giving supporting evidence for the validity of the approach. Predicted SP amplitude exceeds measured in both cases; this is a possible consequence of the Planck approximation. Electrochemical sources account for more than 90% of the predicted response in both cases while thermoelectric mechanisms account for the remaining 10%; electrokinetic effects are not considered. Predicted electrochemical and thermoelectric voltage coupling coefficients are comparable to values measured in the laboratory. The derived relationships are also applied to arbitrary distributions of temperature and fluid composition to investigate the geometric diversity of observed SP anomalies. Amplitudes predicted for hypothetical saline spring and hot spring environments are less than 40 mV. In contrast, hypothetical near surface steam zones generate very large amplitudes, over 2 V in one case. These results should be viewed with some caution due to the uncertain validity of the Planck approximation for these conditions. All amplitudes are controlled by electrochemical mechanisms. Polarities are controlled by the ...
Date: January 1, 1988
Creator: Knapp, R. B. & Kasameyer, P. W.
Partner: UNT Libraries Government Documents Department

Collinear n-body problem of classical electrodynamics

Description: One model for the motion of n charged particles on the x-axis leads to a system of delay differential equations with delays that depend on the unknown trajectories. If appropriate past histories of the trajectories are given, say on (-r,0), then for sufficiently small t greater than or equal to 0 one has a system of n/sup 2/ ordinary differential equations of the form y' = f(t,y) with y(0) = y/sub 0/ given. The function f, which involves the known past histories of the trajectories, is continuous; thus, existence of solutions is assured. However, f does not satisfy the Lipschitz condition usually used for proving uniqueness. The main new result is that the solution of the above equation is unique provided.
Date: January 1, 1980
Creator: Driver, R. D. & Norris, M. J.
Partner: UNT Libraries Government Documents Department

Probing the vacuum with highly charged ions

Description: The physics of the Fermion vacuum is briefly described, and applied to pair production in heavy ion collisions. We consider in turn low energies (<50 MeV/nucleon), intermediate energies (<5 GeV/nucleon), and ultrahigh energies such as would be produced in a ring collider. At high energies, interesting questions of Lorentz and gauge invariance arise. Finally, some applications to the structure of high Z atoms are examined. 14 refs., 11 figs.
Date: January 1, 1987
Creator: Bottcher, C. & Strayer, M.R.
Partner: UNT Libraries Government Documents Department

Absolute wavelength measurement and fine structure determination in /sup 7/Li II

Description: The energy levels of two-electron atoms continue to provide rigorous tests of relativistic quantum theory, and of correlation effects within a multi-particle system. These interactions are determined perturbatively, with several approximations, and theoretical results often differ. It is critical to provide precise measurements of absolute wavelengths connecting these atomic energy levels to obtain a resolution of the precision of the different parts of such complex calculations. In this work, we report a high precision optical measurements in the 1s2s /sup 3/S - 1s2p /sup 3/P multiplet of Li II using fast-beam laser spectroscopy. A collinear interaction using both parallel and antiparallel laser and ion beams allows both for precise elimination of large Doppler shifts, and for a strong kinematic narrowing of the observed resonances, as compared with thermal beam experiments. The wavelengths of the observed resonance fluorescence radiation are determined by comparing them with simultaneously recorded saturated absorption profiles of molecular iodine hyperfine components. In turn, the absolute wavelengths of the iodine lines are obtained from precisely calibrated Fabry-Perot etalon fringes in a separate experiment. The final precision of the Li II wavelengths is 5 parts in 10/sup 9/, which is at a level of precision of 80 ppM of the QED corrections in the transition. 3 refs., 1 figs., 1 tab.
Date: January 1, 1985
Creator: Riis, E.; Berry, H.G.; Poulsen, O.; Lee, S.A. & Tang, S.Y.
Partner: UNT Libraries Government Documents Department

Proceedings of the Workshop on Foundations of the Relativistic Theory of Atomic Structure : Held at Argonne National Laboratory, December 4-5, 1980

Description: Although the Dirac theory of the hydrogen atom was proposed more than half a century ago, extension of the theory and its practical applications to complex atomic spectra took decades to mature. Development of quantum electrodynamics (QED) in its modern form, advances in high precision experimental techniques, and invention of high-speed computers have made atomic spectroscopy one of the most accurate branches of physics today, both in theory and experiment. In addition to a long-standing need to identify line-spectra coming from far and near parts of the universe, necessities such as to test QED further and to provide reliable data for ions in tokamak plasmas require an understanding of the theory of relativistic atomic structure beyond the framework of the original Dirac theory. Twenty articles from the proceedings of the workshop are presented. Contributed papers are grouped into theoretical and experimental subjects and presented after the papers for the second (atomic structure calculations) and third (experiment) sessions of the Workshop. Alphabetical listing of the authors is presented in Appendix 1, program of the Workshop in Appendix 2, and the list of the participants in Appendix 3.
Date: March 1981
Creator: Berry, H. G.; Cheng, K. T.; Johnson, W. R. & Kim, Yong-Ki
Partner: UNT Libraries Government Documents Department

Electron Scattering : Lectures Given at Argonne National Laboratory

Description: This report is an almost verbatim copy of lectures on Electron Scattering given at Argonne National Laboratory in the Fall of 1982 by John Dirk Walecka. Professor Walecka was an Argonne Fellow in the Physics Division from October 1982 to January 1983. The original intent was to type the lecture notes. However, to finish the report in a reasonable time it was necessary to transcribe most of the equations by hand which led to certain notational difficulties. With a single exception in lecture no. 20, pp. 340-359, the notation has been made self-consistent by writing all script and other symbols by hand that are not easily reproduced by a word processor. Certain conventions should be noted. The superscript "ALT 216 symbol" is used to signal a footnote. However, the footnote is usually not to be found on the same page; in fact it may occur only after several intervening pages of text. Instructions are provided for interpreting the symbols representing the products of two vectors, as well as a note that important results are included in a box, with their relative importance being indicated by the number of asterisks associated with the box.
Date: January 1984
Creator: Walecka, John Dirk
Partner: UNT Libraries Government Documents Department

Atomic Physics Aspects of a Relativistic Nuclear Collider

Description: Atomic collision cross sections involving bare uranium nuclei are large at relativistic energies and will affect the design and operation of a relativistic nuclear collider (RNC). The most significant may be production of electron-positron pairs and muon pairs ({approx} 10{sup 8} per sec. and 2000 per sec. respectively for a 100 GeV/nucleon collider with a luminosity of 10{sup 27} cm{sup 2} s{sup -1}). Although the pair production is a direct measure of the luminosity it is also a large source of background and capture of an electron from the pair by one of the nuclei will result in the loss of the ion. Another important loss mechanism is Coulomb excitation of the giant nuclear dipole and giant nuclear quadrupole resonances. Storing and colliding bare and highly-stripped uranium opens up new possibilities for novel atomic physics experiments and an alternate approach for present experiments. As examples, the use of a collider for experiments to study spontaneous decay of the super-critical state (both positron production and x-ray production) of quasi-atoms of atomic number Z > 172, and a storage-ring measurement of the ground state hyperfine structure of hydrogen like thallium as a test of quantum electrodynamics (QED) are discussed.
Date: November 1, 1984
Creator: Gould, R.
Partner: UNT Libraries Government Documents Department

Quarks and gluons in hadrons and nuclei

Description: These lectures discuss the particle-nuclear interface -- a general introduction to the ideas and application of colored quarks in nuclear physics, color, the Pauli principle, and spin flavor correlations -- this lecture shows how the magnetic moments of hadrons relate to the underlying color degree of freedom, and the proton's spin -- a quark model perspective. This lecture reviews recent excitement which has led some to claim that in deep inelastic polarized lepton scattering very little of the spin of a polarized proton is due to its quarks. This lecture discusses the distribution functions of quarks and gluons in nucleons and nuclei, and how knowledge of these is necessary before some quark-gluon plasma searches can be analyzed. 56 refs., 2 figs.
Date: December 1, 1989
Creator: Close, F. E.
Partner: UNT Libraries Government Documents Department

Quarks and gluons in hadrons and nuclei

Description: These lectures discuss the particle-nuclear interface -- a general introduction to the ideas and application of colored quarks in nuclear physics, color, the Pauli principle, and spin flavor correlations -- this lecture shows how the magnetic moments of hadrons relate to the underlying color degree of freedom, and the proton's spin -- a quark model perspective. This lecture reviews recent excitement which has led some to claim that in deep inelastic polarized lepton scattering very little of the spin of a polarized proton is due to its quarks. 38 refs.
Date: January 1, 1989
Creator: Close, F. E.
Partner: UNT Libraries Government Documents Department

Two-photon results from SPEAR

Description: Results obtained by two experiments at SPEAR on the two-photon production of lepton pairs and resonances are reported. Both experiments find agreement of lepton production with QED expectations, and observe an enhancement of the ..pi pi.. mass spectrum in the 1250 MeV/c/sup 2/ region. The Mark II finds this enhancement not consistent with the decay of the f(1270 MeV/c/sup 2/) alone. The ..gamma gamma.. partial width of the eta' has also been measured by the Mark II.
Date: September 1, 1980
Creator: Roussarie, A.
Partner: UNT Libraries Government Documents Department

Study of the reactions e/sup +/e/sup -/. -->. gamma gamma. and e/sup +/e/sup -/. -->. e/sup +/e/sup -/ at 29 GeV

Description: Precise measurements are reported on the reactions e/sup +/e/sup -/ ..-->.. ..gamma gamma.. and e/sup +/e/sup -/ ..-->.. e/sup +/e/sup -/ at the center-of-mass energy of 29 GeV. The study is based on a high statistics sample (integrated luminosity of 164.3 pb/sup -1/) observed in the High Resolution Spectrometer (HRS) at the PEP storage rings. No significant deviations from the expectations of QED theory are found. The ratio of the measured cross section for the reaction e/sup +/e/sup -/ ..-->.. ..gamma gamma.. to that predicted by QED is 1.008 +- 0.008 +- 0.010; the resulting lower bounds (95% confidence level) on the conventional QED-violation parameters are ..lambda../sub +/ = 55 GeV and ..lambda../sub -/ = 64 GeV. 6 refs., 3 figs.
Date: January 1, 1985
Creator: Loos, J.S. & Wood, D.E.
Partner: UNT Libraries Government Documents Department

The particle-nuclear interface

Description: This paper discusses the differences and similarities between modern nuclear physics and particle physics. Similarities are presented between QED and QCD. (LSP)
Date: January 1, 1989
Creator: Close, F.E. (Oak Ridge National Lab., TN (USA)):(Tennessee Univ., Knoxville, TN (USA))
Partner: UNT Libraries Government Documents Department

The structure of constitutive equations for semiconductor devices

Description: The fundamental equations that describe carrier transport in semiconductor materials are developed using the methods of continuum mixture theory and Maxwell's equations for electrodynamics. There are five basic equations that govern the behavior of current flux, electrostatic potential, electrons, and holes. The bahavior of the electrical chemical potentials are introduced and their relation to the current flux is discussed.
Date: January 1, 1987
Creator: Buchanan, G.R.; Girrens, S.P. & Bennett, J.G.
Partner: UNT Libraries Government Documents Department

Tests of QED (Quantum Electrodynamics) to fourth order in alpha in electron-positron collisions at 29 GeV

Description: Tests of Quantum Electrodynamics to order /alpha//sup 4/ in e/sup +/e/sup /minus// collisions using the ASP detector at PEP (/radical/s = 29 GeV) are presented. Measurements are made of e/sup +/e/sup /minus// /yields/ /gamma//gamma//gamma//gamma/, e/sup +/e/sup /minus// /yields/ e/sup +/e/sup /minus///gamma//gamma/ and e/sup +/e/sup /minus// /yields/ e/sup +/e/sup /minus//e/sup +/e/sup /minus// where all four final state particles are separated from the beam line and each other. These are the most precise and highest statistics measurements yet reported for these processes. The ratios of measured to predicted cross sections are /gamma//gamma//gamma//gamma/: 0.97 /plus minus/ 0.04 /plus minus/ 0.14 e/sup /+/e/sup /minus///gamma/gamma/: 0.94 /plus minus/ 0.03 /plus minus/ 0.03 e/sup +/e/sup /minus//e/sup +/e/sup /minus//: 1.01 /plus minus/ 0.02 /plus minus/ 0.04 where the first uncertainty is the systematic uncertainty, and the second is the statistical uncertainty. All measurements show good agreement with theoretical predictions. A Monte Carlo method for simulating multi-pole processes is also presented, along with applications to the e/sup +/e/sup /minus// /yields/ e/sup +/e/sup /minus///gamma//gamma/ and e/sup +/e/sup /minus// /yields/ /gamma//gamma//gamma//gamma/ processes. The first measurements of five-body /alpha//sup 5/ events (/sup 5//gamma/, e/sup +/e/sup /minus///gamma//gamma//gamma/ and e/sup +/e/sup /minus//e/sup +/ e/sup /minus///gamma/) and one candidate six-body /alpha//sup 6/event (e/sup +/e/sup /minus//4/gamma/) are reported. Both the /alpha//sup 5/ and /alpha//sup 6/ measurements agree with estimates of their cross sections. 20 refs., 34 figs., 14 tabs.
Date: February 1, 1989
Creator: Hawkins, C.A.
Partner: UNT Libraries Government Documents Department

Vacuum oscillations around a large-Z ''nucleus''

Description: We investigate a possible explanation of sharp e/sup +/ peaks in heavy-ion collisions by analyzing QED with a large atomic number external source. We show that a highly polarized vacuum around a large Z ''nucleus'' has at least two neutral oscillation modes, whose energies are calculated to be 1.8 MeV and 1.5 MeV with an appropriate choice of the nuclear radius. They decay into a pair of e/sup +-/ through electromagnetic interactions. 8 refs., 1 fig.
Date: January 1, 1989
Creator: Kumano, S. & Iwazaki, A.
Partner: UNT Libraries Government Documents Department

Operator Gauge Transformations in Nonrelativistic Quantum Electrodynamics

Description: A system of nonrelativistic charged particles and radiation is canonically quantized in the Coulomb gauge and Maxwell's equations in quantum electrodynamics are derived. By requiring form invariance of the Schrodinger equation under a space and time dependent unitary transformation, operator gauge transformations on the quantized electromagnetic potentials and state vectors are introduced. These gauge transformed potentials have the same form as gauge transformations in non-Abelian gauge field theories. A gauge-invariant method for solving the time-dependent Schrodinger equation in quantum electrodynamics is given. Maxwell's equations are written in a form which holds in all gauges and which has formal similarity to the equations of motion of non-Abelian gauge fields. A gauge-invariant derivation of conservation of energy in quantum electrodynamics is given. An operator gauge transformation is made to the multipolar gauge in which the potentials are expressed in terms of the electromagnetic fields. The multipolar Hamiltonian is shown to be the minimally coupled Hamiltonian with the electromagnetic potentials in the multipolar gauge. The model of a charged harmonic oscillator in a single-mode electromagnetic field is considered as an example. The gauge-invariant procedure for solving the time-dependent Schrodinger equation is used to obtain the gauge-invariant probabilities that the oscillator is in an energy eigenstate For comparison, the conventional approach is also used to solve the harmonic oscillator problem and is shown to give gauge-dependent amplitudes.
Date: December 1982
Creator: Gray, Raymond Dale
Partner: UNT Libraries

Fixed point structure of quenched, planar quantum electrodynamics

Description: Gauge theories exhibiting a hierarchy of fermion mass scales may contain a pseudo-Nambu-Boldstone boson of spontaneously broken scale invariance. The relation between scale and chiral symmetry breaking is studied analytically in quenched, planar quantum electrodynamics in four dimensions. The model possesses a novel nonperturbative ultraviolet fixed point governing its strong coupling phase which requires the mixing of four fermion operators. 12 refs.
Date: July 1, 1986
Creator: Love, S.T.
Partner: UNT Libraries Government Documents Department

General QED/QCD aspects of simple systems

Description: This paper discusses the following topics: renormalization theory; the Kinoshita-Lee-Nauenberg theorem; the Yennie-Frautschi-Suura relation; scale invariance at large momentum transfer; scaling and scaling violation at large momentum transfers; low-energy theorem in Compton scattering; does the perturbation series in QED converge; renormalization of the weak angle /Theta//sub w/; the Nambu-Bethe-Salpeter (NBS) equation; the decay rate of /sup 3/S, positronium; radiative corrections to QCD Born cross section; and progress on the relativistic 2-body equation.
Date: September 1, 1989
Creator: Telegdi, V.L. & Brodsky, S.J.
Partner: UNT Libraries Government Documents Department

The search for charged-lepton specific forces and the PEGASYS facility

Description: This paper discusses the electroproduction of lepton pairs as a method of searching for a charged-lepton specific force, and as a general method of searching for deviations from conventional quantum electrodynamics. The use of the PEGASYS facility for these purposes is briefly described. Search possibilities in other energy ranges are noted. 22 refs., 11 figs.
Date: February 1, 1989
Creator: Perl, M.L.
Partner: UNT Libraries Government Documents Department

Variational methods for field theories

Description: Four field theory models are studied: Periodic Quantum Electrodynamics (PQED) in (2 + 1) dimensions, free scalar field theory in (1 + 1) dimensions, the Quantum XY model in (1 + 1) dimensions, and the (1 + 1) dimensional Ising model in a transverse magnetic field. The last three parts deal exclusively with variational methods; the PQED part involves mainly the path-integral approach. The PQED calculation results in a better understanding of the connection between electric confinement through monopole screening, and confinement through tunneling between degenerate vacua. This includes a better quantitative agreement for the string tensions in the two approaches. Free field theory is used as a laboratory for a new variational blocking-truncation approximation, in which the high-frequency modes in a block are truncated to wave functions that depend on the slower background modes (Boron-Oppenheimer approximation). This ''adiabatic truncation'' method gives very accurate results for ground-state energy density and correlation functions. Various adiabatic schemes, with one variable kept per site and then two variables per site, are used. For the XY model, several trial wave functions for the ground state are explored, with an emphasis on the periodic Gaussian. A connection is established with the vortex Coulomb gas of the Euclidean path integral approach. The approximations used are taken from the realms of statistical mechanics (mean field approximation, transfer-matrix methods) and of quantum mechanics (iterative blocking schemes). In developing blocking schemes based on continuous variables, problems due to the periodicity of the model were solved. Our results exhibit an order-disorder phase transition. The transfer-matrix method is used to find a good (non-blocking) trial ground state for the Ising model in a transverse magnetic field in (1 + 1) dimensions.
Date: September 1, 1986
Creator: Ben-Menahem, S.
Partner: UNT Libraries Government Documents Department