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in subjects: "Higgs Model"

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Two exercises in supersymmetry: a low-energy supergravity model and free string field theory

The new features of a supersymmetric standard model in the presence of heavy families are studied. The minimal set of Higgs fields, the desert between the electroweak and the grand unification scale and perturbative values of the dimensionless parameters throughout this region are assumed. Using the numerical as well as the approximate analytic solution of the renormalization group equations, the evolution of all the parameters of the theory are studied in the case of large Yukawa couplings for… more

Date: September 1, 1986

Creator: Preitschopf, C.R.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Suppression of superheavy magnetic monopoles in grand unified theories

The superheavy magnetic monopoles predicted by grand unified theories would not be produced in significant numbers if electromagnetic gauge invariance is spontaneously broken when the temperature T is greater than T/sub c/ >approx. 1 TeV.

Date: August 1, 1980

Creator: Pi, S.Y.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Will the next fifteen years of high energy physics match the last fifteen

A brief retrospective of advances in high energy physics made during the last 15 years, both theortical and experimental, is given, followed by predictions for future work, which is said to include testing the standard model and exploring the Higgs sector. The theoretical methods available for understanding the Higgs sector are briefly discussed, as well as available experimental tools. (LEW)

Date: September 1, 1985

Creator: Bjorken, J. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Symmetry breaking patterns for unitary and orthogonal groups

The spontaneous symmetry breaking pattern for SU(n) and 0(10) is discussed. It is based on the exact treatment of the absolute minimum of the Higgs potential as a function of scalar fields belonging to the fundamental and adjoint representations of SU(n), the spinor and adjoint representations of 0(10). 2 tables.

Date: April 1, 1980

Creator: Buccella, F.; Ruegg, H. & Savoy, C.A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Higgs mass scales and matter-antimatter oscillations in grand unified theories

A general discussion of mass scales in grand unified theories is presented, with special emphasis on Higgs scalars which mediate neutron-antineutron (n-anti n) and hydrogen-antihydrogen (H-anti H) oscillations. It is shown that the analogue of survival hypothesis for fermions naturally makes such particles superheavy, thus leading to unobservable lifetimes. If this hypothesis is relaxed, an interesting possibility of potentially observable n-anti n and H-anti H transitions, mutually related ari… more

Date: January 1, 1982

Creator: Senjanovic, G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Masses and mixing angles in SU(5) gauge model

Georgi and Jarlskog mass relations m/sub ..mu../m/sub e/ = 9m/sub s//m/sub d/, m/sub b/ = m/sub tau/ are obtained above the grand unification mass M = 10/sup 15/ GeV with two approx. 5's and one approx. 45 Higgs representations of SU(5) and a discrete symmetry. In the lowest order, the Kobayashi-Maskawa angles are found to be s/sub 2/ = -(m/sub c//m/sub t/) /sup 1/2/ and s/sub 3/ = -(m/sub u//m/sub t/) /sup 1/2//s/sub 1/, where s/sub 1/ is the sine of the Cabibbo angle. The CP violation is cons… more

Date: January 1, 1979

Creator: Nandi, S. & Tanaka, K.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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A search for supersymmetric electrons with the Mark II detector at PEP (Positron Electron Project)

An experimental search for selectrons, the supersymmetric partner of the electron, has been performed at the PEP storage ring at SLAC using the Mark II detector. The experimental search done was based upon hypothetical reaction in e/sup +/e/sup -/ interactions at PEP center of mass energies of 29 GeV. In this reaction the selectrons, e-tilde, are assumed produced by the interaction of one of initial state electrons with a photon radiated from the other initial state electron. This latter electr… more

Date: October 1, 1987

Creator: LeClaire, B.W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Effects of a new heavy neutral vector boson at SLC and LEP

Models with an extra neutral gauge boson (Z') are discussed. We constrain the Z' mass as a function of its mixing angle with the known Z/sup 0/ by requiring that the Z/sup 0/ mass not be shifted excessively by this mixing, and from the Higgs vacuum expectation value structure of the mass matrix. We compare these limits with those previously found from neutral current experiments. We discuss possible effects of non-excluded models on e/sup +/e/sup -/ physics at SLC and LEP. 8 refs., 3 figs.

Date: April 1, 1986

Creator: Franzini, P. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Introduction to lattice gauge theory

The lattice formulation of Quantum Field Theory (QFT) can be exploited in many ways. We can derive the lattice Feynman rules and carry out weak coupling perturbation expansions. The lattice then serves as a manifestly gauge invariant regularization scheme, albeit one that is more complicated than standard continuum schemes. Strong coupling expansions: these give us useful qualitative information, but unfortunately no hard numbers. The lattice theory is amenable to numerical simulations by which… more

Date: January 1, 1987

Creator: Gupta, R.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Collider Aspects of Flavour Physics at High Q

This chapter of the report of the 'Flavour in the era of LHC' workshop discusses flavor related issues in the production and decays of heavy states at LHC, both from the experimental side and from the theoretical side. We review top quark physics and discuss flavor aspects of several extensions of the Standard Model, such as supersymmetry, little Higgs model or models with extra dimensions. This includes discovery aspects as well as measurement of several properties of these heavy states. We al… more

Date: March 7, 2008

Creator: del Aguila, F.; Aguilar-Saavedra, J. A.; Allanach, B. C.; Alwall, J.; Andreev, Yu.; Aristizabal Sierra, D. et al.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Phenomenology of the left-right twin Higgs model

The twin Higgs mechanism was proposed recently to solve the little hierarchy problem. We study the implementation of the twin Higgs mechanism in left-right models. At the TeV scale, heavy quark and gauge bosonsappear, with rich collider phenomenology. In addition, there are extra Higgs bosons, some of which couple to both the standard model fermion sector and the gauge sector, while others couple to the gauge bosons only. We present the particle spectrum and study the general features of the co… more

Date: November 2, 2006

Creator: Goh, Hock-Seng; Goh, Hock-Seng & Su, Shufang

Item Type: Article

Partner: UNT Libraries Government Documents Department

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A Little Twin Higgs Model

We present a twin Higgs model based on left-right symmetry with a tree level quartic. This is made possible by extending the symmetry of the model to include two Z_2 parities, each of which is sufficient to protect the Higgs from getting a quadratically divergent mass squared. Although both parities are brokenexplicitly, the symmetries that protect the Higgs from getting a quadratically divergent mass are broken only collectively. The quadratic divergences of the Higgs mass are thus still prote… more

Date: July 25, 2007

Creator: Goh, Hock-Seng; Goh, Hock-Seng & Krenke, Christopher A.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Restrictions on two Higgs doublet models and CP violation at the unification scale

Bounds on charged Higgs masses and couplings in models with two Higgs doublets are examined that came from CP violation in the neutral K system. Bounds on charged Higgs masses and couplings in two Higgs doublet models are also obtained from their effects on neutral-B-meson mixing. The bounds are found to be comparable to those obtained with additional assumptions from the neutral K system. The three generation phase invariant measure of CP violation is shown to satisfy a simple and solvable ren… more

Date: April 1, 1987

Creator: Athanasiu, G.G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Toponium and two-Higgs models

Bounds from B/sup 0/ - anti B/sup 0/ mixing on charged-Higgs-boson masses and couplings in two-Higgs-doublet models are presented. These bounds are comparable to those obtained, with additional assumptions, from the neutral-K-system. The effects of the neutral Higgs bosons of these models on the spectrum and wave function of toponium are discussed. These effects could, in the future, lead to limits on, or the discovery of, these Higgs bosons. 8 refs., 3 figs.

Date: April 1, 1986

Creator: Franzini, P. J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

e+e- collisions in the multi-TeV region

A leading role in the elucidation of the Standard Model during the last few years has been played by e+e- colliding beam experiments. The e+e- discoveries have been made possible by the cleanliness of the experimental conditions and the ability to tune the centre-of-mass energy with precision to the desired value, thus avoiding less interesting background events. We expect history to repeat itself in the next step of elucidating physics beyond the Standard Model. Just as past e+e- machines such… more

Date: May 1, 1983

Creator: Ellis, J.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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TeV picture

A not-so-standard model of strong and electroweak interactions is discussed. Some direct consequences of this model are discussed and finally the outlook for the future is considered.

Date: June 1, 1981

Creator: Raby, S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Approach to the unification of elementary particle interactions

The assumption that the grand unified theory (GUT) emerges as an effective theory describing bound states of N = 8 supergravity preons should determine the GUT particle spectrum and constrain their couplings. Analysis of the spectrum has led to some possibly encouraging indications. At the least, the particle content in scalars, vectors and fermions needed to reproduce SU(5) phenomenology can be found among the states of the EGMZ multiplet.

Date: September 1, 1981

Creator: Gaillard, M. K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Weak interactions at the SSC

Prospects for the study of standard model weak interactions at the SSC are reviewed, with emphasis on the unique capability of the SSC to study the mechanism of electroweak symmetry breaking whether the associated new quanta are at the TeV scale or higher. Symmetry breaking by the minimal Higgs mechanism and by related strong interaction dynamical variants is summarized. A set of measurements is outlined that would calibrate the proton structure functions and the backgrounds to new physics. The… more

Date: March 1, 1986

Creator: Chanowitz, Michael S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Signatures for strongly interacting W's and Z's

The observed structure of the electroweak interactions is understood in terms of a spontaneously broken gauge theory. Although we have as yet no experimental indication as to the nature of the phenomenon responsible for symmetry breaking, general theoretical arguments set an upper limit of 1 or 2 TeV on the energy scale at which some manifestation of this phenomenon must occur. This scale defines a target for the effective hard collision energy that should be achieved in the next accelerator fa… more

Date: September 1, 1985

Creator: Gaillard, M. K.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Minimally Extended Elctroweak Gauge Theories in SO(10) and E/sub 6/

The possibility of minimally extending the standard SU(2)/sub L/xU(1) electroweak theory within the context of SO(10) and E/sub 6/ grand unification by adding U(1) factors is explored. The neutrino neutral-current interactions in these schemes are arranged to coincide with the standard-model predictions. Limits on the masses of the extra Z's generated by these U(1) factors are obtained by considering other parity-violating effects. Additional Z's as light as 2.5 to 3.0 times the standard model … more

Date: November 1, 1982

Creator: Robinett, R. W. & Rosner, J. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department

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Weak interactions at high energies. [Lectures, review]

Review lectures are presented on the phenomenological implications of the modern spontaneously broken gauge theories of the weak and electromagnetic interactions, and some observations are made about which high energy experiments probe what aspects of gauge theories. Basic quantum chromodynamics phenomenology is covered including momentum dependent effective quark distributions, the transverse momentum cutoff, search for gluons as sources of hadron jets, the status and prospects for the spectro… more

Date: August 1, 1978

Creator: Ellis, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

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Heavy quarks and CP: Moriond 1985

The presentations at the Fifth Moriond Workshop on Heavy Quarks, Flavor Mixing, and CP Violation (La Plagne, France, January 13-19, 1985) are summarized. The following topics are reviewed. What's New (beyond the top, top quarks, bottom quarks, charm quarks, strange quarks, and others); why is all this being done (strong interactions and hadron structure, and electroweak properties); and what next (facilities and can one see CP violation in the B-anti B system). 64 refs., 10 figs.

Date: March 1, 1985

Creator: Bjorken, J. D.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Future frontiers for e/sup +/e/sup -/ collisions: physics of SLC and LEP

A brief historical review is given of the contribution to particle physics of e/sup +/e/sup -/ interactions, followed by a discussion of the LEP and SLC machines and the reasons for developing linear colliders. A brief overview of the Standard Model and some essential formalism for the process e/sup +/e/sup -/ ..-->.. f anti f are presented, followed by a discussion of detectors. Tests of the Standard Model and physics beyond the Standard Model that can be made running at the Z/sup 0/ are consi… more

Date: April 1, 1986

Creator: Dorfan, J. M.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Vacuum expectation values of Higgs scalars in a SU(2)/sub L/ X SU(2)/sub R/ X U(1) gauge model. [Six-quark model]

The vacuum expectation values of the Higgs scalars are determined within the framework of a six quark SU(2)/sub L/ x SU(2)/sub R/ x U(1) gauge model after the imposition of discrete symmetrics that are necessary in order to express the Cabibbo angle in terms of quark mass ratios and phases of the vacuum expectation values. Both real and complex solutions are found for the vacuum expectation values depending on the relative values of the parameters in the Higgs potential.

Date: January 1, 1978

Creator: Kitazoe, T.; Mainland, G. B. & Tanaka, K.

Item Type: Report

Partner: UNT Libraries Government Documents Department