Diffractive Electromagnetic Processes from a Regge Point of View

TL;DR

This paper presents a Regge theory perspective on electromagnetic diffractive processes, explaining their energy dependence with a single pole model and comparing it to an alternative energy-dependent dipole model.

Contribution

It introduces a unified Regge-based framework for describing electromagnetic diffractive processes across a wide energy range, including a novel interpretation of the energy dependence.

Findings

Single power-law energy dependence for cross sections from 20 GeV to 2 TeV.

Unified description of all electromagnetic elastic diffractive processes.

Compatibility of the dipole model with data up to 2 TeV, indicating a cut in the angular momentum plane.

Abstract

The energy dependence of the cross sections for electromagnetic diffractive processes can be well described by a single power, $W^\delta$. For $J/\psi$ photoproduction this holds in the range from 20 GeV to 2 TeV. This feature is most easily explained by a single pole in the angular momentum plane which depends on the scale of the process, at least in a certain range of values of the momentum transfer. It is shown that this assumption allows a unified description of all electromagnetic elastic diffractive processes. We also discuss an alternative model with an energy dependent dipole cross section, which is compatible with the data up to 2 TeV and which shows an energy behaviour typical for a cut in the angular momentum plane.