Glauber Monte-Carlo predictions for LHC

TL;DR

This paper uses Glauber-like models to predict correlation observables in nuclear collisions at SPS, RHIC, and LHC energies, analyzing eccentricity and multiplicity fluctuations with moderate model dependence and comparing to experimental data.

Contribution

It provides a systematic analysis of eccentricity and multiplicity fluctuations across different energies using Glauber models, highlighting their energy dependence and comparison with experimental results.

Findings

Fluctuations of eccentricity vary with collision centrality and model choice.

Multiplicity fluctuations increase by about 20% from RHIC to LHC energies.

Model dependence of scaled eccentricity fluctuations is moderate.

Abstract

In the framework of various Glauber-like models we compute several correlation observables in nuclear collisions at the SPS, RHIC, and LHC energies. We analyze fluctuations of the eccentricity of the fireball created in the collision, in particular the {variable-axes} harmonic moments $\epsilon^\ast$, as well as the fluctuations of multiplicity of charged particles. We find moderate model dependence of the scaled standard deviation $\sigma(\epsilon^\ast)/\epsilon^\ast$ on the choice of the particular Glauber model. For all considered models the values of $\sigma(\epsilon^\ast)/\epsilon^\ast$ range from $\sim$~0.5 for central collisions to $\sim$~0.3-0.4 for peripheral collisions. The results are confronted to the recent measurement of the elliptic-flow fluctuations at RHIC. We also find that the dependence of multiplicity fluctuations on the centrality of the collision is too weak to explain the measurements at the SPS energies. The magnitude of the Glauber multiplicity fluctuations increases by about 20% from the RHIC to LHC energies.