Rapidity gaps and the PHOJET Monte Carlo

TL;DR

This paper discusses a Monte Carlo model for large rapidity gap production in high-energy collisions, incorporating diffraction, QCD, and soft color reconnection, and compares predictions with Tevatron data.

Contribution

It introduces a detailed model for rapidity gaps in proton-proton collisions, combining diffraction, QCD, and soft color reconnection, validated against collider data.

Findings

Model successfully describes diffractive hadron production data

Predicts rapidity gap events at Tevatron energies

Shows non-factorizing flux function due to unitarity corrections

Abstract

A model for the production of large rapidity gaps being implemented in the Monte Carlo event generator PHOJET is discussed. In this model, high-mass diffraction dissociation exhibits properties similar to hadron production in non-diffractive hadronic collisions at high energies. Hard diffraction is described using leading-order QCD matrix elements together with a parton distribution function for the pomeron and pomeron-flux factorization. Since this factorization is imposed on Born graph level only, unitarity corrections lead to a non-factorizing flux function. Rapidity gaps between jets are obtained by soft color reconnection. It was previously shown that this model is able to describe data on diffractive hadron production from the CERN-SPS collider and from the HERA lepton-proton collider. In this work we focus on the model predictions for rapidity gap events in p-p collisions at \sqrt{s} = 1800 GeV and compare to TEVATRON data.