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Some simple criteria for gauged R-parity

Description: Some simple conditions which are sufficient to guarantee that R- parity survives as an unbroken gauged discrete subgroup of the continuous gauge symmetry in certain supersymmetric extensions of the standard model are presented.
Date: July 1, 1992
Creator: Martin, S. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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One-Loop Fluctuation-Dissipation Formula for Bubble-Wall Velocity

Description: The limiting bubble wall velocity during a first-order electroweak phase transition is of interest in scenarios for electroweak baryogenesis. Khlebnikov has recently proposed an interesting method for computing this velocity based on the fluctuation-dissipation theorem. It is demonstrated that at one-loop order this method is identical to simple, earlier techniques for computing the wall velocity based on computing the friction from particles reflecting off or transmitting through the wall in t… more
Date: June 1, 1993
Creator: Arnold, P.
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Partner: UNT Libraries Government Documents Department
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Symmetric textures

Description: The Wolfenstein parametrization is extended to the quark masses in the deep ultraviolet, and an algorithm to derive symmetric textures which are compatible with existing data is developed. It is found that there are only five such textures.
Date: April 1, 1993
Creator: Ramond, P.
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Partner: UNT Libraries Government Documents Department
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A separate Higgs?

Description: We investigate the possibility of a multi-Higgs doublet model where the lightest neutral Higgs boson (h{sup o}) decouples from the fermion sector. We are partially motivated by the four {ell}{sup +}{ell}{sup {minus}} events with M{gamma}{gamma} {approx_equal} 60 GeV recently observed by the L3 collaboration, which could be a signal for Z {yields} (Z{sup *} {yields} {ell}{sup +}{ell}{sup {minus}}) + (h{sup o} {yields} {gamma}{gamma}). Collider signatures for the additional physical Higgs bosons … more
Date: November 1, 1992
Creator: Barger, V.; Deshpande, N. G.; Hewett, J. L. & Rizzo, T. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Oblique Electroweak Corrections From Heavy Scalar Fields

Description: The contributions of heavy scalar fields to the oblique electroweak correction parameters S and T are discussed with an emphasis of the decoupling properties of these contributions. It turns that in the decoupling limit, we also get the custodial symmetry.
Date: November 1, 1992
Creator: Li, Ling-Fong
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Intermediate scales of symmetry breaking in Calabi-Yau models

Description: We discuss the generation of large intermediate scales of symmetry breaking in grand unification models suggested by the heterotic string. We analyze on dimensional grounds a particular scenario where one flat direction in the effective potential defines two different scales of gauge-symmetry breaking at very high energies [{approx}0(10{sup 15}GeV)]. This mechanism implies the presence of one light [0(1 TeV)] nonchiral neutrino. The size of the observable low-energy effects seems, however, quit… more
Date: July 1, 1992
Creator: Masip, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Complementarity of resonant and nonresonant strong WW scattering at SSC and LHC

Description: Signals and backgrounds for strong WW scattering at the SSC and LHC are considered. Complementarity of resonant signals in the I = 1 WZ channel and nonresonant signals in the I = 2 W{sup +}W{sup +} channel is illustrated using a chiral lagrangian with a J = 1 ``p`` resonance. Results are presented for purely leptonic final states in the W{plus_minus}Z, W{sup +}W{sup +} + W{sup {minus}}W{sup {minus}}, and ZZ channels.
Date: August 1, 1992
Creator: Chanowitz, M. S.
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Partner: UNT Libraries Government Documents Department
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Summary of the extensions of the Standard Model working group

Description: The authors summarize the results of the extended gauge group working group of the Madison-Argonne Workshop on Present and Future Colliders. Contributions are described on the previously unexamined two photon fusion production of heavy leptons, new studies of Z{prime} couplings to {nu}{anti {nu}} and q{anti q}, and previously unexplored vector leptoquark production. More detailed accounts of these studies can be found in individual contributions.
Date: September 1, 1993
Creator: Godfrey, S. & Rizzo, T. G.
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Partner: UNT Libraries Government Documents Department
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CP violation in B decays

Description: She reviews how one can test the Standard Model predictions for CP violation. This test requires sufficient independent measurements to overconstrain the model parameters and thus be sensitive to possible beyond Standard Model contributions. She addresses the challenges for theory as well as for experiment to achieve such a test.
Date: February 1, 1994
Creator: Quinn, H. R.
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Partner: UNT Libraries Government Documents Department
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Standard model status (in search of ``new physics``)

Description: A perspective on successes and shortcomings of the standard model is given. The complementarity between direct high energy probes of new physics and lower energy searches via precision measurements and rare reactions is described. Several illustrative examples are discussed.
Date: March 1, 1993
Creator: Marciano, W. J.
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Partner: UNT Libraries Government Documents Department
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Constraints on fermion mixing with exotics

Description: We analyze the constraints on the mixing angles of the standard fermions with new heavy particles with exotic SU(2) {times} U(1) quantum number assignments (left-handed singlets or right-handed doublets), that appear in many extensions of the electroweak theory. The updated Charged Current and Neutral Current experimental data, including also the recent Z-peak measurements, are considered. The results of the global analysis of all these data are then presented.
Date: November 1, 1991
Creator: Nardi, E.; Roulet, E. & Tommasini, D.
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Partner: UNT Libraries Government Documents Department
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Neutrino Oscillations From Discrete Non-Abelian Family Symmetries

Description: The author discusses a SUSY-GUT model with a non-Abelian discrete family symmetry that explains the observed hierarchical pattern of quark and lepton masses. This SO(10) {times} {Delta}(75) model predicts modified quadratic seesaw neutrino masses and mixing angles which are interesting for three reasons: (1) they offer a solution to the solar neutrino problem, (2) the tau neutrino has the right mass for a cosmologically interesting hot dark matter candidate, and (3) they suggest a positive resu… more
Date: November 1, 1994
Creator: Schmaltz, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Mass and mixing angle patterns in the Standard Model and its material Supersymmetric Extension

Description: Using renormalization group techniques, we examine several interesting relations among masses and mixing angles of quarks and lepton in the Standard Model of Elementary Particle Interactions as a functionof scale. We extend the analysis to the minimal Supersymmetric Extension to determine its effect on these mass relations. For a heavy to quark, and minimal supersymmetry, most of these relations, can be made to agree at one unification scale.
Date: January 1, 1992
Creator: Ramond, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Precise determination of the weak mixing angle from a measurement of A{sub LR} in e{sup +}e{sup {minus}} {yields} Z{sup 0}

Description: In the 1993 SLC/SLD run, the SLD recorded 50,000 Z events produced by the collision of longitudinally polarized electrons on unpolarized positrons at a center-of-mass energy of 91.26 GeV. The luminosity-weighted average polarization of the SLC electron beam was (63.0{+-}1.1)%. The authors measure the left-right cross-section asymmetry in Z boson production, A{sub LR}, to be 0.1628{+-}0.0071(stat.){+-}0.0028(syst.) which determines the effective weak mixing angle to be sin{sup 2}{theta}{sup eff}… more
Date: May 1, 1994
Creator: Woods, M.
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Partner: UNT Libraries Government Documents Department
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Superweak-Like Models of CP Violation

Description: I put forward a two-Higgs-doublet model in which CP violation is mediated only by the neutral Higgs bosons, via the mechanism of scalar-pseudoscalar mixing. In this model there is no CP violation in the exchange of either W bosons or of charged Higgs bosons. The model is therefore an approximate realization of the superweak theory of CP violation. It has only two basic CP-violating quantities. I point out that other models of this kind, but with more than two Higgs doublets, may also be built.
Date: June 19, 1992
Creator: Lavoura, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Has a standard model solution to the solar neutrino problem been found?

Description: The claim by Dar and Shaviv that they have found a standard model solution to the solar neutrino problem is base upon an incorrect assumption made in extrapolating nuclear cross sections and the selective use of a small fraction of the nuclear physics and of the neutrino data. In addition, five different solar model codes show that the rate obtained for the chlorine experiment using the Dar- Shaviv stated parameters differs by a least 14{sigma} from the observed rate.
Date: August 1, 1994
Creator: Bahcall, J. N.; Barnes, C. A.; Christensen-Dalsgaard, J.; Cleveland, B. T.; Degl'Innocenti, S.; Filippone, B. W. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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