Rapidity Gaps Between Jets

TL;DR

This paper investigates rapidity gaps between jets at HERA, incorporating a perturbative QCD model into HERWIG to explain observed excesses and predict gap fraction behavior at large rapidity intervals.

Contribution

The paper introduces a perturbative QCD-based colour singlet exchange model into HERWIG, successfully describing the observed rapidity gap events and predicting their increase at larger rapidity intervals.

Findings

HERWIG with the new model matches observed gap event rates

Gap fraction increases with larger rapidity intervals

Predictions depend on extended detector coverage

Abstract

An excess of events with a rapidity gap between jets, over what would be expected from non-diffractive processes, has been observed at HERA. A process based on a perturbative QCD calculation of colour singlet exchange has been added to HERWIG. With this addition, HERWIG is able to describe the number of events with a gap between jets over the number without a gap. This gap fraction is predicted to rise at large rapidity intervals between jets which would only be visible if the detector coverage were increased.