Showing papers on "Electroweak interaction published in 1984"
TL;DR: In this paper, it was shown that the neutral-current experiments determining H-neutral do not restrict mixing of U(1) × U(2)s in an electroweak SU(2,L × U (1)R ×U(1)(B−L)/2) gauge theory, and that there is a second Z in the range 70-110 GeV whose couplings to quarks and leptons are comparable to those of the Z with a mass of 95 GeV.
249 citations
TL;DR: Anomalously large cross sections for multi W and Z final states will occur at SSC energies if electroweak symmetry breaking is due to new strong interactions as mentioned in this paper, which is not the case here.
139 citations
TL;DR: In this paper, a lattice model of SU(2) × U(1) electroweak theory is presented which, in its Higgs phase, reproduces all the features of the continuum model.
136 citations
TL;DR: The experimental limits on the masses and mixings with ordinary neutrinos of these leptons are very poor for masses above about 1 GeV, and suggestions are made for extending these limits, in experiments involving the production of $b$ quarks, $W$ and $Z$ bosons, and any heavier gauge bosons that might exist, and via high-statistics studies of neutral current neutrino interactions as mentioned in this paper.
Abstract: Neutral leptons corresponding to "right-handed neutrinos" are expected in many grand unified theories of the electroweak strong interactions. At present, the experimental limits on the masses and mixings with ordinary neutrinos of these leptons are very poor for masses above about 1 GeV. Suggestions are made for extending these limits, in experiments involving the production of $b$ quarks, $W$ and $Z$ bosons, and any heavier gauge bosons that might exist, and via high-statistics studies of neutral-current neutrino interactions.
118 citations
TL;DR: In this paper, the decoupling of a fermion, rendered heavy through Yukawa interactions, is considered in the standard electroweak theory and the terms induced in the low-energy effective action which depend on the Higgs field and gauge fields precisely cancel all anomalies of the remaining set of light fermions.
105 citations
TL;DR: In this article, a model independent analysis of the super-symmetric electroweak contribution togμ−2 is discussed within the framework of N=1 Supergravity unified theory. But the authors do not consider the effects of the hidden sector and the photino mass dependence.
Abstract: A model independent analysis of the super-symmetric electroweak contribution tog
μ−2 is discussed within the framework ofN=1 Supergravity unified theory. A detailed comparison with existing experiment of two models (R.G. and T.B.) is carried out. The supersymmetric electro-weak contributions are found to be characteristically different and generally larger than the electro-weak contributions of the standard theory, and in many cases significantly larger. Effects of the hidden sector and the photino mass dependence ofg
μ−2 are also investigated. Present data already eliminates some choices of parameters. Reduction of existing experimental errors by a factor of 3 will make contact with most R.G. models and by a factor of 10 with most T.B. models.
96 citations
TL;DR: In this article, various methods are discussed to measure the electroweak production properties of τ pairs in e+e− annihilation and their weak decay properties through an analysis of the hadronic system in semileptonic τ decays.
94 citations
TL;DR: In this article, the O2N Higgs-Goldstone model was shown to be a good indicator of the behavior of the standard SU2 ⊗ U1 electroweak model in the non-perturbative limit of a strongly interacting Higgs sector.
68 citations
TL;DR: In this paper, the authors discuss the motivation for constructing composite models for quarks and leptons, the hopes for a successful model and the difficulties encountered, so far, in this field.
64 citations
TL;DR: In this article, a comprehensive review of theoretical and experimental studies of parity nonconservation in atoms is presented, including measurements in bismuth, lead, cesium, and thallium which collectively provide confirmation of the Weinberg-Salam-Glashow "standard model" of electroweak unification.
55 citations
01 Jan 1984
TL;DR: In this article, the authors present a collection of papers divided under different topics, such as physics, acyclic detectors, detectors, Vizier reports, and Electroweak symmetry breaking.
Abstract: This book contains papers divided under different topics. The topics are: Physics; Acclerators; Detectors; Vizier Reports; and Workshop on Electroweak Symmetry Breaking. Some of the sections include: Compositeness; W Pair Identification; Rare Decays and CP Violations; Jets and Large P/sub T/; Dynamic Aperture and Tracking; Fixed-Target Options and Test Beams; and Fixed-Internal Target Option.
TL;DR: In this article, the electroweak $\ensuremath{rho}$ parameter is examined in a general class of supersymmetric models, including scalar quarks and leptons, and an extra doublet of Higgs scalars.
Abstract: The electroweak $\ensuremath{\rho}$ parameter is examined in a general class of supersymmetric models. Formulas are given for one-loop contributions to $\ensuremath{\Delta}\ensuremath{\rho}$ from scalar quarks and leptons, gauge and Higgs fermions, and an extra doublet of Higgs scalars. Mass differences between members of isodoublet scalar quarks and leptons are constrained to be less than about 200 GeV.
TL;DR: In this paper, it is argued that a charge-conjugation conserving lagrangian provides the most reasonable version of the theory, leading to phenomenological consequences which differ from those of the so-called manifest left-right symmetry.
TL;DR: In this article, the mass limits for new quarks at CM energies between 39.8 and 45.2 GeV and a search was made for new heavy quarks and no evidence was found for the existence of a narrow state in this mass range.
TL;DR: In this paper, the authors investigated the hypothesis that the observed weak interactions are the residual interactions of quasi Goldstone fermions and showed that left-handed quarks and leptons arise from the spontaneous symmetry breaking U(6) → U(4) × SU(2) in a supersymmetric theory.
TL;DR: In this paper, a globally supersymmetric QCD was proposed to account for the discrepancy between the experimental value of the K L -K S mass difference and that obtained from the electroweak model.
TL;DR: In this paper, the possibility of isolating single electroweak structure functions in deep inelastic lepton-nucleon scattering at Q 2 around M 2 1 /2 2 /
Abstract: The possibility is studied of isolating single electroweak structure functions in deep inelastic lepton-nucleon scattering atQ
2 aroundM
2
. Utilizing the cross-section dependence on the lepton charge and longitudinal polarization λ it is shown that the most-conclusive results follow from measurements of σ+(−λ)±σ−(+λ). Considerable simplifications of the problem are possible if λ can be tuned to sin2 θ dependent values of about 0.2. New quark-parton model relations are derived.
TL;DR: In this paper, a special class of locally supersymmetric models has been found which can produce a phase transition that meets all the conditions necessary for the inflationary universe scenario and which sets, via spontaneous supersymmetry breaking, a mass hierarchy consistent with the electroweak unification scale.
CERN1
TL;DR: In this paper, the electroweak gauge group is broken according to a dynamical scenario based on the chiral symmetry breaking of high colour representations, which requires also the existence of elementary Higgs fields.
[...]
CERN1
TL;DR: Radiative Z 0 decays from the point of view that weak bosons are nonstandard composite objects which interact strongly with each other are analyzed in this article, where they are shown to be non-uniform composite objects.
TL;DR: In this article, the SU(5) model was shown to be stable for the double, triple, quadruple, and sextuple magnetic monopoles with multiple Dirac charge.
Abstract: Magnetic monopoles with multiple Dirac charge are found to be stable in grand unified theories with symmetry breaking by an adjoint Higgs field under certain conditions. In the SU(5) model, the double, triple, quadruple, and sextuple monopoles are stable for a range of parameters in the Higgs potential. The effects of electroweak symmetry breaking on multiply charged monopoles are discussed. Evidence is also presented for the existence of a stable nonspherically symmetric quadruple monopole.
TL;DR: In this paper, the self-couplings of the electroweak gauge bosons were modified by the inclusion of an arbitrary W magnetic-moment parameter kappa, the analog for the ZWW coupling kappa/sub Z/, and a parameter..omega.., measuring the relative strengths of the Z WW and gamma-gamma..WW couplings; in the standard SU(2)/sub L/ x U(1) theory these parameters are all, at tree level, unity.
Abstract: We investigate the possibility of using the reaction e/sup +/e/sup -/..-->..W/sup +/W/sup -/ as a probe of the self-interactions of the electroweak gauge bosons. We modify the self-couplings of these bosons by the inclusion of an arbitrary W magnetic-moment parameter kappa, the analog for the ZWW coupling kappa/sub Z/, and a parameter ..omega.., measuring the relative strengths of the ZWW and ..gamma..WW couplings; in the standard SU(2)/sub L/ x U(1) theory these parameters are all, at tree level, unity. We calculate the dependence of the potentially observable decay-lepton angular distribution on kappa, kappa/sub Z/, and ..omega.. and present the dependence of the total and angular differential cross sections on these parameters. We first present results appropriate to CERN LEP II and then discuss the advantages of both a polarized-beam machine at ..sqrt..s = 260 GeV and of a super-LEP operating at ..sqrt..s = 500 GeV.
TL;DR: In this paper, an analysis of electroweak leptonic couplings from high statistics experiments on Bhabha scattering and μ pair production at an energy of 34.5 GeV was presented.
Abstract: We present an analysis of electroweak leptonic couplings from high statistics experiments on Bhabha scattering and μ pair production at an energy of 34.5 GeV. The forward-backward charge asymmetry of the μ pairs was measured to be −0.098±0.023±0.005. The data were found to agree well with the standard theory of electroweak interaction giving sin2θW=0.27±0.07. The leptonic weak couplings were determined to begv=0.000±0.170 andgA=−0.481±0.055. The data were also used to investigate a class of composite models for leptons.
TL;DR: In this article, the grand unification mass mX can be computed in terms of the lengths of the extra compact dimensions: m X = (10π h /3L 5(6) c)n, where n is a fixed integer (or possibly a half-integer).
TL;DR: In this paper, the authors discuss the phenomenological implications of lepto-quark Higgs bosons present in some electroweak models and consider experimental signatures in pp and e + e − experiments.
TL;DR: In this article, the electromagnetic and purely weak one-loop corrections to e + e − → + − have been calculated in the SU(2) × U(1) standard model using an on-shell renormalisation scheme with finite Green functions.
TL;DR: In this paper, the electromagnetic radiative corrections to Z-exchange have been shown to reduce the charge asymmetry up to 1% which is mainly caused by virtual and soft photon parts of the corrections.
Abstract: The electromagnetic radiative corrections toe+e−-annihilation into lepton pairs are calculated including hard photon bremsstrahlung in the standard and extended electroweak models. For\(\sqrt s \) = 38 GeV we find for the standard model, that the radiative corrections toZ-exchange reduce the charge asymmetry up to 1% which is mainly caused by the virtual and soft photon parts of the corrections. For models with a higher forward-backward asymmetry the situation is found to be quite similar.
TL;DR: In this paper, the breaking of isospin symmetry in the electroweak theory with a dynamical Higgs sector is analyzed and the natural size of the breaking in various amplitudes is estimated, given that the breaking is very large in the fermion mass matrix.
Abstract: The breaking of isospin symmetry in the electroweak theory with a dynamical Higgs sector is analyzed. The natural size of the breaking in various amplitudes is estimated, given that the breaking is very large in the fermion mass matrix. Special attention is paid to the parameter rhoequivalentM/sub w//sup 2//M/sub z//sup 2/cos /sup 2/theta/sub w/ . Hypercolor models are then investigated. There it is noted that rho-1 will naturally exhibit a sensitive, linear dependence on the fermion-doublet mass splittings.
TL;DR: A thorough numerical analysis of the two major improvements of the original MIT bag model is presented in this article, where it is shown that the c.m. motion correction alone gives a good fit to hadron masses (including the qq pion).