Probing Hard Color-Singlet Exchange in ppbar Collisions at root-s=630 GeV and 1800 GeV

TL;DR

This paper investigates dijet production via hard color-singlet exchange in proton-antiproton collisions at two energies, measuring the color-singlet fraction's dependence on various kinematic variables, and finds results inconsistent with two-gluon models.

Contribution

It provides the first detailed measurements of the color-singlet exchange fraction at different energies and kinematic conditions, challenging existing two-gluon exchange models.

Findings

Color-singlet fraction increases with quark-initiated process fraction.

Results are inconsistent with two-gluon exchange models.

The fraction varies with jet transverse energy and pseudorapidity separation.

Abstract

We present results on dijet production via hard color-singlet exchange in proton-antiproton collisions at root-s = 630 GeV and 1800 GeV using the DZero detector. The fraction of dijet events produced via color-singlet exchange is measured as a function of jet transverse energy, separation in pseudorapidity between the two highest transverse energy jets, and proton-antiproton center-of-mass energy. The results are consistent with a color-singlet fraction that increases with an increasing fraction of quark-initiated processes and inconsistent with two-gluon models for the hard color-singlet.