Finite size scaling on the phase diagram of QCD

TL;DR

This paper discusses how finite size scaling techniques can be used to analyze QCD phase transitions, including locating the critical point and extracting the crossover temperature from experimental and lattice data.

Contribution

It introduces finite size scaling methods to identify the QCD critical point and analyze phase diagram features from existing data.

Findings

QCD crossover temperature can be extracted from fluctuation data.

The QCD critical point can be located using finite size scaling.

Systematic uncertainties in current analyses are identified.

Abstract

In the last years there has been remarkable progress in the comparison of experimental data on the shape of event-by-event distributions of conserved quantities and lattice thermodynamic predictions based on the grand canonical ensemble. In this talk we discuss how the QCD crossover temperature and the freezeout curve are extracted from the analysis of fluctuations. We report that one can also go further and locate the QCD critical point already from published data. We also list the systematics which must be brought under control in future.