[en] Agreement of theoretical calculations with the observed production rate of bottom quarks at hadron colliders is improved by the introduction of a contribution from pair-production of light gluinos, of mass 12 to 16 GeV, having two-body decays into bottom quarks and light bottom squarks with mass congruent with 2 to 5.5 GeV. Predictions are made for hadronic and radiative decays of the Upsilon states. In the limit of large tan β, the dominant decay mode of the light scalar Higgs boson is into a pair of light bottom squarks that materialize as jets of hadrons

[en] A calculation is presented of the radiative decay of the Υ(nS) into a bound state of bottom squarks. Predictions are provided of the branching fraction as a function of the masses of the bottom squark and the gluino. Branching fractions as large as several times 10^-4 are obtained for supersymmetric particle masses in the range suggested by the analysis of bottom-quark production cross sections. Data are shown that limit the range of allowed masses. Forthcoming high-statistics data from the CLEO Collaboration offer possibilities of discovery or significant new bounds on the existence and masses of supersymmetric particles

No abstract available

[en] Single-top-squark production via qq^'→t(tilde sign) ₁ probes R -parity-violating extensions of the minimal supersymmetric standard model through the λ^''_3ij couplings. For masses in the range 180-325 GeV, and λ^''_3ij>0.02- 0.06 , we show that discovery of the top squark is possible with 2 fb^-1 of integrated luminosity at run II of the Fermilab Tevatron. The bound on λ^''_3ij can be reduced by up to 1 order of magnitude with existing data from run I, and by 2 orders of magnitude at run II if the top squark is not found. (c) 1999 The American Physical Society

[en] We study the s-channel production of a single top squark in hadron collisions through an R-parity-violating mechanism, examining in detail the case in which the squark decays through an R-parity-conserving process into a bottom quark, a lepton, and missing energy. We show that the top squark can be discovered if its mass is less than 400 GeV, or that the current bound on the size of the R-parity-violating couplings can be reduced by up to one order of magnitude with existing data and by two orders of magnitude at the forthcoming run II of the Fermilab Tevatron

[en] We present complete results of a next-to-leading order calculation of the production of gaugino-like charginos (tilde χ^±) and neutralinos (tilde χ⁰) in association with gluinos (tilde g) at hadron colliders, including the strong corrections from the exchange of colored particles and sparticles. Adopting a variety of models for the sparticle mass spectrum, including typical supergravity (SUGRA) models and a light gluino model, we provide predictions for total and differential cross sections at the energies of the Fermilab Tevatron and CERN Large Hadron Collider (LHC)

[en] The weak boson fusion process for neutral Higgs boson production is investigated with particular attention to the accuracy with which the Higgs boson couplings to weak bosons can be determined in final states that contain a Higgs boson plus at least two jets at CERN Large Hadron Collider energies. We determine that an accuracy of δg/g - 10% on the effective coupling g may be possible after the accumulation of ∼200 fb^-1 of integrated luminosity. (author)

[en] Parton distribution functions for protons are devised in which a light gluino is included along with standard model quark, antiquark, and gluon constituents. A global analysis of a large set of hadronic scattering data provides empirical constraints on the allowed range of the gluino mass m_g tilde as a function of the value of the strong coupling strength α_s(M_Z). We find that m_g tilde > 12 GeV for the standard model world-average value α_s(M_Z)=0.118. Gluino masses as small as 10 GeV are admissible provided that α_s(M_Z) ≥ 0.12, about one standard deviation above the world-average value. Current hadron scattering data are insensitive to the presence of gluinos heavier than ∼100 - 150 GeV. (author)

[en] It has been known for a long time that the cross section for bottom-quark b production at hadron collider energies exceeds theoretical expectations. An additional contribution from pair-production of light gluinos g-tilde, of mass 12 to 16 GeV, with two-body decays into bottom quarks and light bottom quarks b-tilde, helps to obtain a b production rate in better agreement with data. The masses of the g-tilde and b-tilde are restricted further by the ratio of like-sign to opposite-sign leptons at hadron colliders. Constraints on this scenario from other data are examined, and predictions are made for various processes such as Upsilon decay into b-tilde's

[en] After a brief review of the production dynamics of prompt single photons in hadron collisions, I summarize a new QCD calculation of the transverse momentum distribution of continuum prompt photon pairs produced by QCD subprocesses, including all-orders soft-gluon resummation valid at next-to-next-to-leading logarithmic accuracy. Resummation is necessary to obtain reliable predictions, as well as good agreement with data from the Fermilab Tevatron, in the range of transverse momentum where the cross section is largest. Predictions are made for the Large Hadron Collider where the QCD diphoton continuum is shown to have a softer spectrum in transverse momentum than the Higgs boson signal