Measurement of Dijet Azimuthal Decorrelations at Central Rapidities in pp-bar Collisions at sqrt(s)=1.96 TeV

TL;DR

This paper measures how the angular correlation between the two highest momentum jets varies in proton-antiproton collisions at 1.96 TeV, testing predictions of perturbative QCD and soft effects.

Contribution

It provides the first detailed measurement of dijet azimuthal decorrelations at this energy and compares results with next-to-leading order QCD predictions.

Findings

Azimuthal correlations increase with jet transverse momentum.

Perturbative QCD describes the data well except at large azimuthal differences.

Soft effects become significant at large azimuthal decorrelations.

Abstract

Correlations in the azimuthal angle between the two largest transverse momentum jets have been measured using the D0 detector in pp-bar collisions at a center-of-mass energy sqrt(s)=1.96 TeV. The analysis is based on an inclusive dijet event sample in the central rapidity region corresponding to an integrated luminosity of 150 pb-1. Azimuthal correlations are stronger at larger transverse momenta. These are well-described in perturbative QCD at next-to-leading order in the strong coupling constant, except at large azimuthal differences where soft effects are significant.