In the field theoretical description of hadronic scattering processes, single transverse-spin asymmetries arise due to gluon initial and final state interactions. These interactions lead to process dependent Wilson lines in the operator definitions of transverse momentum dependent parton distribution functions. In particular for hadron–hadron scattering processes with hadronic final states this...

We present a new resummation formula for the Drell-Yan cross section. The formal resummation of threshold corrections in Drell-Yan hard-scattering functions produces an exponent with singularities from the infrared pole of the QCD running coupling. Our reformulation treats such ‘infrared renormalons’ by a principal value prescription, analogous to a modified Borel transform. The resulting expre...

“Static” structure functions are the probabilistic distributions computed from the square of the light-front wavefunctions of the target hadron. In contrast, the “dynamic” structure functions measured in deep inelastic lepton-hadron scattering include the effects of rescattering associated with the Wilson line. Initialand final-state rescattering, neglected in the parton model, can have a profo...

An up-to-date global QCD analysis of high energy lepton-hadron and hadron-hadron interactions is performed to better determine the gluon and quark parton distributions in the nucleon. Improved experimental data on inclusive jet production, in conjunction with precise deep inelastic scattering data, place good constraints on the gluon over a wide range of x; while new data on asymmetries in Drel...

A simple model is presented for the parton distributions in hadrons. The parton momenta in the hadron rest frame are derived from a spherically symmetric, Gaussian, distribution having a width motivated by the Heisenberg uncertainty relation applied to the hadron size. Valence quarks and gluons originate from the ‘bare’ hadron, while sea partons arise mainly from pions in hadronic fluctuations....

We discuss some properties of the Pomeron in high energy elastic hadron-hadron and deep inelastic lepton-hadron scattering. A number of issues concerning the nature and the origin of the Pomeron are briefly recalled here. The novelty in this paper resides essentially in its presentation; we strive at discussing all these various issues in the following unifying perspective : it is our contentio...

Even though quantum chromodynamics is a broken conformal theory, the AdS/CFT correspondence has led to important insights into the properties of QCD. For example, as shown by Polchinski and Strassler, dimensional counting rules for the power-law falloff of hadron scattering amplitudes follow from dual holographic models with conformal behavior at short distances and confinement at large distanc...

Recent global QCD analyses of high energy lepton-hadron and hadron-hadron interactions are reviewed. New data on asymmetries in Drell-Yan and W-lepton-asymmetry processes contribute to better determine the d=u ratio; while improved experimental data on inclusive jet production, in conjunction with precise deep inelastic scattering data, place good constraints on the gluon over a wide range of x...

Abstract Light strongly interacting supersymmetric particles may be treated as partonic constituents of nucleons in high energy scattering processes. We construct parton distribution functions for protons in which a light gluino is included along with standard model quark, antiquark, and gluon constituents. A global analysis is performed of a large set of data from deep-inelastic lepton scatter...

HERWIG is a general-purpose Monte Carlo event generator, which includes the simulation of hard lepton-lepton, lepton-hadron and hadron-hadron scattering and soft hadron-hadron collisions in one package. It uses the parton-shower approach for initialand final-state QCD radiation, including colour coherence effects and azimuthal correlations both within and between jets. This article updates the ...