Charged particle jet measurements with the ALICE experiment in proton-proton collisions at the LHC

TL;DR

This paper reports measurements of charged particle jet properties in proton-proton collisions at 7 TeV using ALICE, comparing different jet algorithms and models, and analyzing jet structure and collimation.

Contribution

First measurements of charged particle jets at 7 TeV with ALICE, comparing multiple jet algorithms and models, and analyzing jet structure and collimation.

Findings

Good agreement among different jet finders for uncorrected spectra.

Mean charged particle multiplicity increases with jet pT and matches model predictions.

High pT jets are more collimated than low pT jets.

Abstract

We present preliminary results of measurements of charged particle jet properties in proton-proton collisions at $\sqrt{s}$ = 7 TeV using the ALICE detector. Jets are reconstructed using $\rm anti-k_{T}, k_{T}$ and SISCone jet finding algorithms with resolution parameter $R=0.4$ in the range of transverse momentum from 20 to 100 GeV/$c$ in the midrapidity region ($\mid\eta\mid\textless$ 0.5). The uncorrected charged jet spectra obtained using the three different jet finders show good agreement. The data are compared to predictions from PYTHIA-Perugia0, PYTHIA-Perugia2011, and PHOJET. The mean charged particle multiplicity in leading jets increases with increasing jet $p_{\rm T}$ and is consistent with model predictions. The radial distributions of transverse momentum about the jet direction and the distributions of the average radius containing 80% of the total jet $p_{\rm T}$ found in the jet cone ($R = 0.4$ in this analysis), indicate that high $p_{\rm T}$ jets are more collimated than low $p_{\rm T}$ jets.