Measurements of the fluctuations of identified particles in ALICE at the LHC

TL;DR

This paper presents ALICE experiment results on event-by-event fluctuations of identified particles in Pb-Pb collisions at 2.76 TeV, providing insights into the properties of the quark-gluon plasma and nuclear matter phase diagram.

Contribution

It introduces measurements of net-proton, net-kaon, and net-pion fluctuations, including correlated fluctuations, using the novel Identity Method in heavy-ion collisions.

Findings

Net-proton fluctuations depend on centrality and pseudorapidity.

Correlated fluctuations between different particle species vary with multiplicity and energy.

Results are compared with Monte Carlo models to understand underlying physics.

Abstract

The event-by-event fluctuations of identified particles in ultrarelativistic nucleus-nucleus collisions give information about the state of matter created in these collisions as well as the phase diagram of nuclear matter. In this proceedings, we present the latest results from ALICE on the centrality and pseudorapidity dependence of net-proton fluctuations, which are closely related to net-baryon fluctuations, as well as net-kaon and net-pion fluctuations. The effects of volume fluctuations and global baryon conservation on these observables are discussed. Furthermore, the correlated fluctuations between different particle species, quantified by the observable $\nu_{dyn}$, are also shown as functions of multiplicity and collision energy and are compared with Monte Carlo models. These measurements are performed in Pb-Pb collisions at $\sqrt{s_{\mathrm{NN}}} = 2.76$ TeV using the novel Identity Method and take advantage of the excellent particle identification capabilities of ALICE.