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Few group collapsing of covariance matrix data based on a conservation principle

Description: A new algorithm for a rigorous collapsing of covariance data is proposed, derived, implemented, and tested. The method is based on a conservation principle that allows preserving at a broad energy group structure the uncertainty calculated in a fine group energy structure for a specific integral parameter, using as weights the associated sensitivity coefficients.
Date: June 24, 2008
Creator: Hiruta,H.; Palmiotti, G.; Salvatores, M.; Arcilla, Jr., R.; Oblozinsky, P. & McKnight, R.D.
Partner: UNT Libraries Government Documents Department

Supersymmetric lepton flavor violation at the NLC

Description: Supersymmetric theories generally have new flavor violation sources in the squark and slepton mass matrices. If significant lepton flavor violation exists, selectron and smuon should be nearly degenerate. This leads to the phenomenon of slepton oscillations, which is analogous to neutrino oscillations, if sleptons are produced at the Next Linear Collider. The direct slepton production at the Next Linear Collider provides a much more powerful probe of lepton flavor violation than the current bounds from rare processes, such as {mu} {r_arrow} e{gamma}. 4 refs., 1 fig.
Date: April 1, 1997
Creator: Cheng, Hsin-Chia
Partner: UNT Libraries Government Documents Department

R-parity violation in superstring derived models

Description: The ALEPH collaboration has recently reported a significant excess of four-jet events at the LEP 1.5 and LEP 2 experiments. While not yet confirmed by the other collaborations, it was recently proposed that this excess may be explained by certain R-parity violating operators in supersymmetric models. R-parity violating operators introduce the danger of inducing rapid proton decay. The author discusses how the operators required to explain the ALEPH four jet events may arise from superstring derived models without inducing rapid proton decay.
Date: December 1, 1996
Creator: Faraggi, A.E.
Partner: UNT Libraries Government Documents Department

Lattice and continuum theories

Description: The authors investigate path integral formalism for continuum theory. It is shown that the path integral for the soft modes can be represented in the form of a lattice theory. Kinetic term of this lattice theory has a standard form and potential term has additional nonlocal terms which contributions should tend to zero in the limit of continuum theory. Contributions of these terms can be estimated. It is noted that this representation of path integral may be useful to improve lattice calculations taking into account hard modes contribution by standard perturbative expansion. They discuss translation invariance of correlators and the possibility to construct a lattice theory which keeps rotary invariance also.
Date: April 1, 1994
Creator: V.M.Belyaev
Partner: UNT Libraries Government Documents Department

Knot invariants and the thermodynamics of lattice gas automata. Final technical report, April 15, 1991--July 14, 1995

Description: The goal of this project has been to build on the understanding of the connections between knot invariants, exactly solvable statistical mechanics models and discrete dynamical systems gained in earlier work, toward an answer to the question of how early and robust thermodynamic behavior appears in lattice gas automata. These investigations have recently become relevant, unanticipatedly, to crucial issues in quantum computation.
Date: December 1, 1995
Creator: Meyer, D.A.
Partner: UNT Libraries Government Documents Department

Report of the working group on CP violation and rare decays

Description: It has been pointed out that, with its high energy and luminosity, the SSC may provide the best or only way in which CP violation in heavy meson decays or the rare decay modes of such mesons can be observed. The major problem in the exploitation of the high rates of heavy quark production is the identification of interesting decays in the midst of a large background of more conventional processes. There have been some optimistic reports on the feasibility of such experiments, but relatively little quantitative backup has been provided. In the present report, we concentrate exclusively on B-meson decays. As is the case for K mesons, but not for charm or top decays, the favored modes are suppressed by the smallness of Cabibbo-Kobayashi-Maskawa angles, and therefore rare modes are relatively more frequent and potentially easier to observe.
Date: October 1, 1984
Creator: Cronin, J.W.; Deshpande, N.G.; Kane, G.L.; Luth, V.C.; Odian, A.C.; Machacek, M.E. et al.
Partner: UNT Libraries Government Documents Department

Why is B-L conserved and baryon number not in unified models of quarks and leptons

Description: Conservation of B-L and nonconservation of B are shown to follow simply from the weak isospin properties of quarks and leptons; namely that left-handed particles and right-handed antiparticles have weak isospin 1/2, that all other fermions are singlets, and that particles with half-integral isospin can only be created or annihilated in pairs.
Date: June 1, 1980
Creator: Lipkin, H.J.
Partner: UNT Libraries Government Documents Department

The riddle of high-energy baryon number violation

Description: The exciting possibility that anomalous baryon and lepton number violation might be observable at the next generation of supercolliders is suggested by an instanton calculation due to Ringwald and Espinosa. In these Lectures, the current controversial status of these claims is discussed, and several new technologies designed to analyze this question are reviewed. These technologies should contribute more generally to our understanding of weakly- coupled field theories in the nonperturbative regime where both energies and multiplicities are very large. 61 refs., 35 figs.
Date: September 1, 1991
Creator: Mattis, M.P.
Partner: UNT Libraries Government Documents Department

Conservation laws in the monopole-fermion system

Description: It is shown that the monopole induced baryon number non-conservation is a necessary consequence of the exact conservation laws of the full four dimensional fermion-gauge field-Higgs system and properties of the J=0 partial wave fermions. It is also shown that the charge associated with the unbroken gauge symmetry is exactly conserved in the monopole-fermion interaction. 11 references.
Date: December 1, 1983
Creator: Sen, A.
Partner: UNT Libraries Government Documents Department

Duality rotations

Description: Irrespective of supersymmetry, it is interesting to understand the special properties of theories admitting duality rotations. The Lagrangian of such a theory is not invariant under the transformations, nor does it change by a total derivative, but it transforms in a particular way which implies that the system of the equations of motion is invariant and that observables, such as the energy momentum tensor and therefore the total energy and momentum, are invariant. The main results of a recent paper on the properties of theories admitting duality rotations written in collaboration with M. K. Gaillard (1981) are described.
Date: November 1, 1981
Creator: Zumino, B.
Partner: UNT Libraries Government Documents Department

This was the particle physics that was: The years from P and C violation to CP violation

Description: This paper contains lecture notes given by Gary Feinberg on the historical aspect of the violation of P and C invariance and more recently the violation of CP invariance. (LSP) 13 refs., 2 figs., 2 tabs.
Date: February 17, 1989
Creator: Feinberg, G. (Columbia Univ., New York, NY (USA). Dept. of Physics)
Partner: UNT Libraries Government Documents Department

Parity violation in nuclei

Description: A summary of parity violating effects in nuclei is given. Thanks to vigorous experimental and theoretical effort, it now appears that a reasonably well-defined value for the weak isovector ..pi..-nucleon coupling constant can be obtained. There is one major uncertainty in the analysis, namely the M2/E1 mixing ratio for the 2.79 MeV transition in /sup 21/Ne. This quantity is virtually impossible to calculate reliably and must be measured. If it turns out to be much larger than 1, then a null result in /sup 21/Ne is expected no matter what the weak interaction, so an experimental determination is urgently needed. The most promising approach is perhaps a measurement of the pair internal conversion coefficient. Of course, a direct measurement of a pure isovector case is highly desirable, and it is to be hoped that the four ..delta..T = 1 experiments will be pushed still further, and that improved calculations will be made for the /sup 6/Li case. Nuclear parity violation seems to be rapidly approaching an interesting and useful synthesis.
Date: January 1, 1980
Creator: Robertson, R.G.H.
Partner: UNT Libraries Government Documents Department

Parity anomalies in gauge theories in 2 + 1 dimensions

Description: We show that the introduction of massless fermions in an abelian gauge theory in 2+1 dimensions does not lead to any parity anomaly despite a non-commutativity of limits in the structure function of the odd part of the vacuum polarization tensor. However, parity anomaly does exist in non-abelian theories due to a conflict between gauge invariance under large gauge transformations and the parity symmetry. 6 refs.
Date: January 1, 1986
Creator: Rao, S. & Yahalom, R.
Partner: UNT Libraries Government Documents Department

Tests of time reversal invariance via transmission experiments

Description: The existing formalism used to describe spin observables in neutron transmission experiments is found to be inadequate. A suitable formalism is developed, through which time-reversal violating (and parity non-conserving) forward scattering amplitudes are identified, along with their corresponding spin observables. It is noted that new and more precise tests of T-symmetry are provided in transmission experiments and that such investigations are applicable more generally in nuclear and particle physics.
Date: June 1, 1989
Creator: Conzett, H.E.
Partner: UNT Libraries Government Documents Department

Dynamics of symmetry breaking in strongly coupled QED

Description: I review the dynamical structure of strong coupled QED in the quenched planar limit. The symmetry structure of this theory is examined with reference to the nature of both chiral and scale symmetry breaking. The renormalization structure of the strong coupled phase is analysed. The compatibility of spontaneous scale and chiral symmetry breaking is studied using effective lagrangian methods. 14 refs., 3 figs.
Date: October 1, 1988
Creator: Bardeen, W.A.
Partner: UNT Libraries Government Documents Department

Formation of galaxies

Description: The present theories of galaxy formation are reviewed. The relation between peculiar velocities and the correlation function of galaxies points to the possibility that galaxies do not form uniformly everywhere. Scale invariant properties of the cluster-cluster correlations are discussed. Comparing the correlation functions in a dimensionless way, galaxies appear to be stronger clustered, in contrast with the comparison of the dimensional amplitudes of the correlation functions. Theoretical implications of several observations as Lyman-..cap alpha.. clouds, correlations of faint galaxies are discussed. None of the present theories of galaxy formation can account for all facts in a natural way. 29 references.
Date: December 1, 1984
Creator: Szalay, A.S.
Partner: UNT Libraries Government Documents Department

Tests of quantum mechanics at a {phi}-factory

Description: Unique tests of quantum mechanics, which can only be performed at a 0-factory, are proposed for Da0ne. Each of these tests consists of measuring the difference between the predicted and the actual amount of interference between two processes leading from a single pure initial state to a single pure final state of a kaon system. Estimates are made of the upper limits that will be set for the amount of violation if the predictions of quantum mechanics turn out to be correct. They are of the order a fraction of one percent. For the case where, on the contrary, a significant violation is found, several decoherence mechanisms are considered.
Date: August 9, 1994
Creator: Eberhard, P.H.
Partner: UNT Libraries Government Documents Department