Study of Jet Shapes in Inclusive Jet Production in pp Collisions at sqrt(s) = 7 TeV using the ATLAS Detector

TL;DR

This study measures jet shapes in proton-proton collisions at 7 TeV using the ATLAS detector, revealing how jet structure varies with transverse momentum and rapidity, and testing QCD models against experimental data.

Contribution

It provides detailed measurements of jet shapes at 7 TeV and evaluates the performance of various QCD-based Monte Carlo models in describing these shapes.

Findings

Jets become narrower with higher transverse momentum.

Jet shapes show moderate dependence on rapidity.

Data are well described by tuned Monte Carlo models.

Abstract

Jet shapes have been measured in inclusive jet production in proton-proton collisions at sqrt(s) = 7 TeV using 3 pb^{-1} of data recorded by the ATLAS experiment at the LHC. Jets are reconstructed using the anti-kt algorithm with transverse momentum 30 GeV < pT < 600 GeV and rapidity in the region |y| < 2.8. The data are corrected for detector effects and compared to several leading-order QCD matrix elements plus parton shower Monte Carlo predictions, including different sets of parameters tuned to model fragmentation processes and underlying event contributions in the final state. The measured jets become narrower with increasing jet transverse momentum and the jet shapes present a moderate jet rapidity dependence. Within QCD, the data test a variety of perturbative and non-perturbative effects. In particular, the data show sensitivity to the details of the parton shower, fragmentation, and underlying event models in the Monte Carlo generators. For an appropriate choice of the parameters used in these models, the data are well described.