We present the handbag contribution to Wide Angle Compton Scattering (WACS) at moderately large momentum transfer obtained with a proton distribution amplitude close to the asymptotic form. In comparison it is found to be significantly larger than results from the hard scattering (pQCD) approach.

Consistent values for the fundamental dimensional coupling constants of hadrons to their valence quarks are determined from large momentum transfer elastic scattering, photoproduction, form factors, and momentum distributions. We then show that the constituent interchange model hard scattering subprocesses Mq-Mq and Bq-Bq (and their crossing variants) are of sufficient magnitude to account for ...

Through a direct implementation of the saturation regime resulting from the unitarity limit in the impact parameter representation, we explore various possibilities for the energy dependence of hadronic scattering. We show that it is possible to obtain a good description of the scattering amplitude from a hard pomeron provided one includes non-linear effects.

Modern materials science and engineering relies increasingly on detailed knowledge of the structure and interactions in “soft” and “hard” materials, but there have been surprisingly few microscopic techniques for probing the structures of bulk samples of these substances. Small-angle neutron scattering SANS was first recognized in Europe as a major technique for this purpose and, over the past ...

We propose stringy hadronic amplitudes that combine some of the features of sister trajectories and running tension. By summing over string amplitudes with varying Regge trajectories that have integer tension and converging intercept, we obtain parton hard-scattering and Regge soft-scattering behaviors, while preserving discrete poles in both momentum and angular momentum. PACS : 11.25.Pm, 11.2...

A detailed proof of hard scattering factorization is given with the inclusion of heavy quark masses. Although the proof is explicitly given for deep-inelastic scattering, the methods apply more generally The power-suppressed corrections to the factorization formula are uniformly suppressed by a power of Λ/Q, independently of the size of heavy quark masses, M , relative to Q.

In the hard pomeron model consequences are studied which follow from the recently obtained form of the diffractive amplitude for the double scattering on the nucleus and the related EMC effect at small x. It is shown that at large Q2 the double scattering contribution to the latter falls as Q−0.6338 and in all probability dominates the total effect.

Through a direct implementation of the saturation regime resulting from the unitarity limit in the impact parameter representation, we explore various possibilities for the energy dependence of hadronic scattering. We show that it is possible to obtain a good description of the scattering amplitude from a hard pomeron provided one includes non-linear effects.

Initialand final-state rescattering, neglected in the parton model, have a profound effect in QCD hard-scattering reactions, predicting single-spin asymmetries, diffractive deep inelastic scattering, diffractive hard hadronic reactions, the breakdown of the Lam Tung relation in DrellYan reactions, and nuclear shadowing and non-universal antishadowing—leading-twist physics not incorporated in th...

Off-diagonal parton distributions occur in several hard exclusive reactions. They extend the study of hadron structure beyond what can be learned from ordinary distributions and have a particularly rich spin structure. The hard scattering subprocesses in electroproduction of mesons and of real photons satisfy helicity selection rules, which provide powerful tools to test leading-twist dominance...