# Quark Matter 2012

12-18 August 2012
US/Eastern timezone

## Beam energy and centrality dependence of the statistical moments of the net-charge multiplicity distribution in Au+Au collisions at STAR

17 Aug 2012, 16:50
20m
Regency 2/3 ()

### Regency 2/3

Oral Presentation

### Speaker

Daniel McDonald (R)

### Description

In part to search for a possible critical point (CP) in the phase diagram of hot nuclear matter, a beam energy scan was performed at the Relativistic Heavy-Ion Collider at Brookhaven National Laboratory. The STAR experiment collected significant Au+Au data sets at beam energies, $\sqrt{\rm s_{\rm NN}}$, of 7.7, 11.5, 19.6, 27, 39, 62.4 and 200 GeV. Lattice and phenomenological calculations suggest that the presence of a CP might result in divergences of the thermodynamic susceptibilities and correlation lengths [1,2]. The statistical moments of the multiplicity distributions of particles reflecting conserved quantities, {\it e.g.} net-charge and net-strangeness, are expected to depend sensitively on these correlation lengths, making them attractive tools for the search of a possible critical point. In this talk, the centrality and beam energy dependence of the statistical moments of the net-charge multiplicity distributions will be presented. The observables studied include the lowest four statistical moments (mean, variance, skewness, kurtosis), products of these moments, and the intensive normalized cumulants [2]. The measured moments of the net-Kaon and total-pion multiplicity distributions will also be presented. These will be compared to the predictions from approaches lacking critical behavior, such as the Hadron Resonance Gas model [3] and Poisson statistics. References [1] M. Cheng {\it et al.}, Phys. Rev. D 79, 074505 (2009). [2] C. Athanasiou {\it et al.}, Phys. Rev. D 82, 074008 (2010), M. Stephanov, Phys. Rev. Lett. 107, 052301 (2011). [3] F. Karsch and K. Redlich, Phys. Lett. B 695, 136 (2011).

 Slides

Paper files: