Role of baryons in chiral-symmetry restoration at high temperature

To help provide insight into the apparent remarkable rise in baryon susceptibility at the high-temperature phase transition in QCD, we study the three-dimensional lattice SU(2) chiral model at finite temperature. The purpose of this study is to determine the extent to which a rising susceptibility is a natural consequence of chiral-symmetry restoration in a nonlinear <T model. Indeed the susceptibility, defined in terms of a discrete (nonconserved) version of the winding number, is found to rise rapidly in the vicinity of the phase transition, suggesting that a proliferation of baryons and antibaryons (i.e., Skyrmions) plays a significant role in the restoration of the chiral symmetry. These results support the idea that the cooling of the quark plasma could result in copious antibaryon production.