Baryon Density Correlations in High Temperature Hadronic Matter

TL;DR

This paper investigates baryon density correlations in high temperature QCD matter using numerical simulations, revealing weak correlations at high temperature and large baryonic screening near the crossover temperature, indicating a transition to deconfined quark-gluon plasma.

Contribution

It provides new numerical evidence on baryon density behavior and cluster sizes across the QCD crossover, enhancing understanding of the deconfinement transition.

Findings

Weak baryon density correlations at high temperature

Large baryonic screening near crossover temperature

Growth of color singlet clusters approaching deconfinement

Abstract

As part of an ongoing effort to characterize the high temperature phase of QCD, in a numerical simulation using the staggered fermion scheme, we measure the quark baryon density in the vicinity of a fixed test quark at high temperature and compare it with similar measurements at low temperature and at the crossover temperature. We find an extremely weak correlation at high temperature, suggesting that small color singlet clusters are unimportant in the thermal ensemble. We also find that at $T = 0.75\ T_c$ the total induced quark number shows a surprisingly large component attributable to baryonic screening. A companion simulation of a simple flux tube model produces similar results and also suggests a plausible phenomenological scenario: As the crossover temperature is approached from below, baryonic states proliferate. Above the crossover temperature the mean size of color singlet clusters grows explosively, resulting in an effective electrostatic deconfinement.