Edmond L. Berger

Diffractive hard scattering

Abstract We discuss high energy hadron collisions that contain a hard scattering, in the sense that a W, a Z, very heavy quarks, or high p T jets are produced, yet are diffractive, in the sense that one of the incident hadrons is scattered with only a small energy loss. In our approach, the cross section for such diffractive hard scattering is a part of the normal hard scattering inclusive cross section, as calculated using perturbative quantum chromodynamics. We use Regge phenomenology in combination with perturbative QCD to estimate that a substantial fraction (perhaps 30%) of all hard scattering events are diffractive. Measurement of diffractive hard scattering cross sections would illuminate the short distance gluon and quark content of the pomeron, which has been found to play a fundamental role in forward hadron scattering.

Higgs boson production in weak boson fusion at next-to-leading order

The weak boson fusion process for neutral Higgs boson production is investigated with particular attention to the accuracy with which the Higgs boson coupling to weak bosons can be determined at CERN Large Hadron Collider energies in final states that contain a Higgs boson plus at least two jets. Using fully differential perturbative matrix elements for the weak boson fusion signal process and for the QCD background processes, we generate events in which a Higgs boson is produced along with two jets that carry large transverse momentum. The effectiveness of different prescriptions to enhance the signal-to background ratio is studied, and the expected signal purities are calculated in each case. We find that a simple cut on the rapidity of one final-state jet works well. We determine that an accuracy of

Associated production of a top quark and a charged Higgs boson

\ensuremath{\delta}g/g\ensuremath{\sim}10%

Low-Energy Supersymmetry and the Tevatron Bottom-Quark Cross Section

on the effective coupling

Rapidity correlations at fixed multiplicity in cluster emission models

g

Large-pT production of single and double photons in proton-proton and pion-proton collisions

may be possible after

Characteristics and Estimates of Double Parton Scattering at the Large Hadron Collider

\ensuremath{\sim}200\text{ }\text{ }{\mathrm{f}\mathrm{b}}^{\ensuremath{-}1}

Multiplicity distributions and inclusive spectra in a multiperipheral cluster emission model

of integrated luminosity is accumulated at the Large Hadron Collider.

Differential cross section for Higgs boson production including all-orders soft gluon resummation

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.

Photon pair production with soft gluon resummation in hadronic interactions

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.