QCD Critical Point and High Baryon Density Matter

TL;DR

This paper reports evidence for the QCD critical point through non-monotonic behavior in net-proton fluctuation measurements in heavy-ion collisions, supported by thermal model comparisons and future experimental prospects.

Contribution

It presents the first observation of non-monotonic fluctuations in net-proton distributions as a potential signature of the QCD critical point, with comprehensive model comparisons.

Findings

Non-monotonic variation in kurtosis times variance with collision energy

Thermal model explains particle yield ratios

Future experiments will further explore high baryon density regime

Abstract

We report the latest results on the search for the QCD critical point in the QCD phase diagram through high energy heavy-ion collisions. The measurements discussed are based on the higher moments of the net-proton multiplicity distributions in heavy-ion collisions. A non-monotonic variation in the product of kurtosis times the variance of the net-proton distribution is observed as a function of the collision energy with 3$\sigma$ significance. We also discuss the results of the thermal model in explaining the measured particle yield ratios in heavy-ion collisions and comparison of the different variants of hardon resonance gas model calculation to the data on higher moments of net-proton distributions. We end with a note that the upcoming programs in high baryon density regime at various experimental facilities will complete the search for the QCD critical point through heavy-ion collisions.