Amplitudes are derived for the quantum-chromodynamic subprocess yg+(J/$)g, with a specific wave function used to represent the . I / $ as a cFsystem. The results are used to obtain the normalized total cross section a, for the inelastic process yN--t(J/$)X, predictions for the z and p , dependence of inelastic .I/$ photoproduction, and predictions for the .I/$ helicity. The predictions apply as well to electroproduction at small Q2.

Physics at the Large Hadron Collider (LHC) and the International e + e − Linear Collider (ILC) will be complementary in many respects, as has been demonstrated at previous generations of hadron and lepton colliders. This report addresses the possible interplay between the LHC and ILC in testing the Standard Model and in discovering and determining the origin of new physics. Mutual benefits for the physics programme at both machines can occur both at the level of a combined interpretation of Hadron Collider and Linear Collider data and at the level of combined analyses of the data, where results obtained at one machine can directly influence the way analyses are carried out at the other machine. Topics under study comprise the physics of weak and strong electroweak symmetry breaking, supersymmetric models, new gauge theories, models with extra dimensions, and electroweak and QCD precision physics. The status of the work that has been carried out within the LHC / LC Study Group so far is summarised in this report. Possible topics for future studies are outlined.4

A detailed analysis of Z y production at hadron colliders is presented for general Z Z y and Z y y couplings. Deviations from the standard model gauge theory structure can be parametrized in terms of four Z Z y and four Z y y form factors. The high-energy behavior of these form factors is severely restricted by unitarity. Prospects for testing the self-interactions of Z bosons and photons at the Fermilab Tevatron, the CERN Large Hadron Collider and the Superconducting Super Collider are explored. Sensitivity limits for anomalous Z Z y and Z y y couplings are derived and compared to bounds from low-energy data and e + e -collider experiments. PACS numberk): 13.85.Qk, 12.15.Cc, 13.38. -tc

High-precision analyses of supersymmetry parameters aim at reconstructing the fundamental supersymmetric theory and its breaking mechanism. A well defined theoretical framework is needed when higher-order corrections are included. We propose such a scheme, Supersymmetry Parameter Analysis SPA, based on a consistent set of conventions and input parameters. A repository for computer programs is provided which connect parameters in different schemes and relate the Lagrangian parameters to physical observables at LHC and high energy e + e − linear collider experiments, i.e., masses, mixings, decay widths and production cross sections for supersymmetric particles. In addition, programs for calculating high-precision low energy observables, the density of cold dark matter (CDM) in the universe as well as the cross sections for CDM search experiments are included. The SPA scheme still requires extended efforts on both the theoretical and experimental side before data can be evaluated in the future at the level of the desired precision. We take here an initial step of testing the SPA scheme by applying the techniques involved to a specific supersymmetry reference point.

The polarization properties and longitudinal momentum distribution * Work supported by the Department of Energy under contract number EY-76-C-03-0515.

A long-standing discrepancy between the bottom-quark production cross section and predictions of perturbative quantum chromodynamics is addressed. We show that pair production of light gluinos, of mass 12 to 16 GeV, with two-body decays into bottom quarks and light bottom squarks, yields a bottom-quark production rate in agreement with hadron collider data. We examine constraints on this scenario from low-energy data and make predictions that may be tested at the next run of the Fermilab Tevatron collider.

We compute the inclusive and differential cross sections for the associated production of a top quark along with a charged Higgs boson at hadron colliders to next-to-leading order (NLO) in perturbative quantum chromodynamics (QCD) and in supersymmetric QCD. For small Higgs boson masses we include top quark pair production diagrams with subsequent top quark decay into a bottom quark and a charged Higgs boson. We compare the NLO differential cross sections obtained in the bottom parton picture with those for the gluon-initiated production process and find good agreement. The effects of supersymmetric loop contributions are explored. Only the corrections to the Yukawa coupling are sizable in the potential discovery region at the CERN Large Hadron Collider (LHC). All expressions and numerical results are fully differential, permitting selections on the momenta of both the top quark and the charged Higgs boson.

A detailed analysis of Wy production and radiative W decays at the Fermilab Tevatron is presented for general WWy couplings. Possibilities to test the gauge structure of the WWy vertex are explored. At the Tevatron, for an integrated luminosity of 100 pb-', the WWy vertex can be measured with 2540 % accuracy in Wy production. The limits which can be obtained from radiative Wdecays are found to be significantly weaker.