Jet Decorrelation and Jet Shapes at the Tevatron

TL;DR

This paper reports measurements of jet shapes and azimuthal decorrelation in proton-antiproton collisions at 1.8 TeV, comparing data with QCD predictions and Monte Carlo models to understand jet behavior.

Contribution

It provides detailed experimental data on jet shapes and decorrelation, testing the accuracy of QCD calculations and Monte Carlo models at Tevatron energies.

Findings

Jets narrow with increasing transverse energy and rapidity.

HERWIG predicts jet shapes and decorrelation trends well.

NLO QCD captures qualitative features but is sensitive to parameters.

Abstract

We present results on measurements of jet shapes and jet azimuthal decorrelation from $\overline{p}p$ collisions at $\sqrt{s}=1.8$ TeV using data collected during the 1992--1993 run of the Fermilab Tevatron. Jets are seen to narrow both with increasing $E_T$ and increasing rapidity. While HERWIG, a parton shower Monte Carlo, predicts slightly narrower jets, it describes the trend of the data well; NLO QCD describes qualitative features of the data but is sensitive to both renormalization scale and jet definitions. Jet azimuthal decorrelation has been measured out to five units of pseudorapidity. While next--to--leading order QCD and a leading--log approximation based on BFKL resummation fail to reproduce the effect, HERWIG describes the data well.