Overlap between Lattice QCD and HRG with in-medium effects and parity doubling

Abstract

Abstract. We investigate the fluctuations and correlations involving baryon number in hot hadronic matter with modified masses of negative-parity baryons, in the context of the hadron resonance gas. Temperature-dependent masses are adopted from the recent lattice QCD results and from a chiral effective model which implements the parity doubling structure with respect to the chiral symmetry. Confronting the baryon number susceptibility, baryon-charge correlation, and baryon-strangeness correlation and their ratios with the lattice QCD data, we show that the strong downward mass shift in hyperons can accidentally reproduce some correlation ratios, however it also tends to overshoot the individual fluctuations and correlations. This indicates, that in order to correctly account for the influence of the chiral symmetry restoration on the fluctuation observables, a consistent framework of in-medium effects beyond hadron mass shifts is required.

Parity Doubling in QCD Thermodynamics

“…[4], the observed medium modification was used to possibly explain a missing contribution in correlations among the conserved charges, in the context of the in-medium Hadron Resonance Gas (HRG) model. In the following, we examine the fluctuations and correlations of the net-baryon with net-charge and net-strangeness on the basis of the standard HRG, the in-medium HRG and the chiral approach [5]. In particular, we focus on the quantities χ B 2 , χ BQ 11 , and χ BS 11 at µ B = µ Q = µ S = 0.…”

“…In this contribution, we briefly summarize our recent study on the thermodynamics of parity doubling: the in-medium masses of baryon octet and decuplet and their potential influence over fluctuations and correlations in the context of a chiral effective theory [3] and in-medium Hadron Resonance Gas (HRG) model [4,5], as well as the physics of neutron stars in a hybrid approach for hadrons and quarks [6].…”