Particle Correlation Results from the ALICE Experiment at LHC

TL;DR

This paper presents two-particle correlation measurements in Pb--Pb collisions at 2.76 TeV, revealing jet shape broadening in pseudorapidity and consistent particle ratios with vacuum fragmentation, enhancing understanding of jet quenching.

Contribution

It provides detailed analysis of jet shapes and particle ratios in heavy-ion collisions, offering new insights into medium effects on jet fragmentation at LHC energies.

Findings

Jet shape broadening in pseudorapidity with centrality

Near-side p/π ratio matches vacuum fragmentation

RMS of peak in azimuthal angle remains constant

Abstract

Measurements of two-particle correlations of inclusive and identified charged particles performed with the ALICE detector in Pb--Pb collisions at $\sqrt{s_{NN}} = 2.76 TeV$ are presented. The near-side jet shape is analyzed in the low $p_{\rm T}$ regions ($1<$p_{\rm T}$<8GeV/c$). While the RMS of the peak in $\Delta\varphi$-direction is independent of centrality within uncertainties, we find significant broadening in $\Delta\eta$-direction from peripheral to central collisions. The near-side $p/\pi$ ratio of particles associated to a trigger particle from jet fragmentation in the central Pb--Pb collisions is consistent with vacuum fragmentation in the measured momentum region ($1.5<$p_{\rm T}$<4.5GeV\c$).