Diffractive Photon Production in Gamma-P and Gamma-Gamma Interactions

TL;DR

This paper investigates diffractive photon production in gamma-p and gamma-gamma collisions at high momentum transfer, providing theoretical rate calculations within perturbative QCD and exploring behavior at various virtualities.

Contribution

It offers the first detailed perturbative QCD calculations of diffractive photon production rates in gamma-p and gamma-gamma interactions, including the -t -> 0 limit.

Findings

Calculated rates for gamma*-p -> gamma-X at large -t

Analyzed gamma*-gamma* -> gamma-gamma process at various virtualities

Provided insights into the -t -> 0 behavior of the process

Abstract

We study the diffractive production of photons in gamma-p and gamma-gamma collisions. We specifically compute the rates for gamma*-p -> gamma-X and for gamma*-gamma* -> gamma-gamma, where X denotes the proton dissociation. We focus on the rates at large momentum transfers, -t >> Lambda^2, where we are most confident in the use of QCD perturbation theory. However, our calculations do allow us to study the -t -> 0 behaviour of the gamma*-gamma*-> gamma-gamma process in the region where the incoming photons are sufficiently virtual.