Baryon Number Fluctuations in Two Flavor NJL Model

TL;DR

This paper investigates baryon number fluctuations using the two-flavor NJL model, comparing theoretical predictions with experimental data from heavy-ion collisions to understand the QCD phase transition.

Contribution

It demonstrates that the two-flavor NJL model can effectively describe baryon number fluctuations and their energy dependence in heavy-ion collision experiments.

Findings

NJL model fits experimental data better at high energies.

Obvious fluctuations observed at small collision energies.

Model sensitive to temperature and chemical potential parameters.

Abstract

Baryon number fluctuations are believed to be good signatures of the QCD phase transition and its CP. Since the fluctuations are proportional to the various order baryon-number susceptibilities and the quark-number density is related to the dressed quark propagator, then by the two flavor NJL model we can calculate the moments of the up and down quarks. By comparing the two flavor NJL model results with the experimental data of $S\sigma$ and $\kappa\sigma^2$ for the net-proton distributions of Au+Au collisions by STAR, we found that the NJL results fit the experiments better at large collision energies and show an obvious fluctuation at small energies. And this fluctuation reflect that the two flavor NJL model is sensitive to the parameters of temperature $T$ and quark chemical potential $\mu$ at small collision energies.