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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

A scenario for estimating the charge on the electron in terms of Planck's constant and the speed of light

Description: The conjecture that the electron might be a soliton of a non-linearly generalized, charge-free electromagnetic field, together with an estimate of the strength of the hypothetical non-linearity (based on the standard QED calculation of the scattering of light by light) leads to an estimate of the soliton's charge, -e, such that hC/e/sup 2/ turns out to be equal to 45..pi.. multiplied by a number of order one, whose precise value depends on the details of the soliton's radial form factor. 6 refs.
Date: May 1, 1987
Creator: Swiatecki, W.J.
Partner: UNT Libraries Government Documents Department

Higgs phase in non-Abelian gauge theories

Description: A non-Abelian gauge theory involving scalar fields with non-tachyonic mass terms in the Lagrangian is considered, in order to construct a finite energy density trial vacuum for this theory. The usual scalar potential arguments suggest that the vacuum of such a theory would be in the perturbative phase. However, the obvious choices for a vacuum in this phase, the Axial gauge and the Coulomb gauge bare vacua, do not have finite energy densities even with an ultraviolet cutoff. Indeed, it is a non-trivial problem to construct finite energy density vacua for non-Abelian gauge theories and this is intimately connected with the gauge fixing degeneracies of these theories. Since the gauge fixing is achieved in the Unitary gauge, this suggests that the Unitary gauge bare vacuum might be a finite energy trial vacuum and, despite the form of the scalar potential, the vacuum of this theory might be in a Higgs phase rather than the perturbative phase.
Date: June 1, 1981
Creator: Kaymakcalan, O.S.
Partner: UNT Libraries Government Documents Department

Elementary particle theory

Description: The present state of the art in elementary particle theory is reviewed. Topics include quantum electrodynamics, weak interactions, electroweak unification, quantum chromodynamics, and grand unified theories. 113 references. (WHK)
Date: December 1, 1984
Creator: Marciano, W.J.
Partner: UNT Libraries Government Documents Department

Relativity: X-ray and auger transitions of highly charged ions

Description: Many-electron QED correction is one of the unsolved problems in relativistic atomic structure calculations for many-electron systems. The accuracy of the effective-charged screening approach frequently used in the MCDF model to estimate the many-electron QED corrections is examined. The effects of relativity and configuration interaction are simultaneously important in the treatment of highly-charged ions. These effects can sometimes change the transition rates by orders of magnitude; numerous irregularities present in Auger rates and oscillator strengths along the isoelectronic sequence due to the level crossings. The spin-orbit mixing and Breit interaction are responsible for the decay of most of the high-spin metastable autoionizing states. 29 refs., 8 figs.
Date: March 6, 1989
Creator: Chen, Mau Hsiung
Partner: UNT Libraries Government Documents Department

New results on Bhabha scattering at 29 GeV

Description: New results are given on Bhabha scattering at the center-of-mass energy of 29 GeV, based on a sample having an integrated luminosity of 165 pb/sup -1/ observed in the High Resolution Spectrometer (HRS) at the PEP colliding beam facility. The measured differential cross sections are used to evaluate Standard Model parameters, lower bound limts on QED cutoff parameters, and lower bound limits on composite model parameters. 10 refs., 1 fig., 3 tabs.
Date: January 1, 1985
Creator: Loos, J.S. & Wood, D.E.
Partner: UNT Libraries Government Documents Department

Proceedings of the workshop on opportunities for atomic physics using slow, highly-charged ions

Description: The study of atomic physics with highly-charged ions is an area of intense activity at the present time because of a convergence of theoretical interest and advances in experimental techniques. The purpose of the Argonne ''Workshop on Opportunities for Atomic Physics Using Slow, Highly-Charged Ions'' was to bring together atomic, nuclear, and accelerator physicists in order to identify what new facilities would be most useful for the atomic physics community. The program included discussion of existing once-through machines, advanced ion sources, recoil ion techniques, ion traps, and cooler rings. One of the topics of the Workshop was to discuss possible improvement to the ANL Tandem-Linac facility (ATLAS) to enhance the capability for slowing down ions after they are stripped to a high-charge state (the Accel/Decel technique). Another topic was the opportunity for atomic physics provided by the ECR ion source which is being built for the Uranium Upgrade of ATLAS. 18 analytics were prepared for the individual papers in this volume.
Date: January 1, 1987
Creator: Available, Not
Partner: UNT Libraries Government Documents Department

Results from HRS at PEP

Description: The High Resolution Spectrometer (HRS) has been collecting data at PEP since the end of 1981 and has now accumulated 120 pb/sup -1/ of integrated luminosity. The results of analyses are presented in the following areas: (1) QED and electroweak tests, (2) scalar electron search, (3) inclusive hadron production, (4) D/sup 0/, D/sup +/ and D* production, and studies of quark fragmentation. Only the 20 pb/sup -1/ of integrated luminosity obtained during our first year of running has been completely analyzed and this provides the data sample for most of the above topics. For others a preliminary analysis of a total sample of 80 pb/sup -1/ is reported. 20 references.
Date: January 1, 1983
Creator: Weiss, J.M.
Partner: UNT Libraries Government Documents Department

Non-linear vacuum polarization in strong fields

Description: The Wichmann-Kroll formalism for calculating the vacuum polarization density to first order in ..cap alpha.. but to all orders in Z..cap alpha.. is derived. The most essential quantity is shown to be the electrons Green's function in these calculations. The method of constructing that Green's function in the field of finite radius nuclei is then presented.
Date: July 1, 1981
Creator: Gyulassy, M.
Partner: UNT Libraries Government Documents Department

The standard model and beyond

Description: The field of elementary particle, or high energy, physics seeks to identify the most elementary constituents of nature and to study the forces that govern their interactions. Increasing the energy of a probe in a laboratory experiment increases its power as an effective microscope for discerning increasingly smaller structures of matter. Thus we have learned that matter is composed of molecules that are in turn composed of atoms, that the atom consists of a nucleus surrounded by a cloud of electrons, and that the atomic nucleus is a collection of protons and neutrons. The more powerful probes provided by high energy particle accelerators have taught us that a nucleon is itself made of objects called quarks. The forces among quarks and electrons are understood within a general theoretical framework called the ''standard model,'' that accounts for all interactions observed in high energy laboratory experiments to date. These are commonly categorized as the ''strong,'' ''weak'' and ''electromagnetic'' interactions. In this lecture I will describe the standard model, and point out some of its limitations. Probing for deeper structures in quarks and electrons defines the present frontier of particle physics. I will discuss some speculative ideas about extensions of the standard model and/or yet more fundamental forces that may underlie our present picture. 11 figs., 1 tab.
Date: May 1, 1989
Creator: Gaillard, M.K.
Partner: UNT Libraries Government Documents Department

Nonlinear electrodynamics in cytoskeletal protein lattices

Description: Cytoskeletal lattice proteins including microtubules are particularly involved in dynamic regulation of intracellular movements and activities. This paper considers possibilities and implications of biological information processing due to coupling of Davydov solitons, Frohlich coherent oscillations and other nonlinear electrodynamic phenomena to conformational states of the grid-like polymer subunits of cytoskeletal microtubules. 39 references.
Date: January 1, 1983
Creator: Hameroff, S.R.; Smith, S.A. & Watt, R.C.
Partner: UNT Libraries Government Documents Department