Measurement of jet $p_{\mathrm{T}}$ spectra in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76~\mathrm{TeV}$ with the ALICE detector at the LHC

TL;DR

This paper presents measurements of jet transverse momentum spectra in lead-lead collisions at 2.76 TeV using the ALICE detector, addressing background subtraction and unfolding techniques for accurate jet reconstruction.

Contribution

First full jet spectra measurement in Pb-Pb collisions at 2.76 TeV with detailed background correction and unfolding methods.

Findings

Jet spectra are successfully reconstructed in heavy-ion collisions.

Background fluctuations are effectively corrected through unfolding.

Results provide insights into jet quenching phenomena.

Abstract

Reconstruction of jets in high-energy heavy-ion collisions is challenging due to the large and fluctuating background coming from the underlying event. We report results on full jet reconstruction, obtained from data collected in 2011 by the ALICE detector at LHC for Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}}=2.76~\mathrm{TeV}$. The analysis makes use of the tracking system and the electromagnetic calorimeter. Signal jets, which come from hard scattered partons, are reconstructed using the anti-$k_{\mathrm{T}}$ jet finder algorithm. The average background is subtracted on a jet-by-jet basis to reduce the contribution to the jet reconstructed energy coming from the underlying event. The jet spectrum is corrected to account for fluctuations in the background momentum density and detector effects through unfolding.