2024/12/19 by 陈晨, Fei Gao, Chen, Chen +3 · 1 citation
Physics and Astronomy · #Quantum Chromodynamics and Particle Interactions #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies
paper · pdf · doi:10.48550/arxiv.2412.15045
Using a symmetry-preserving treatment of a vector × vector contact interaction (SCI) at nonzero temperature, we compute the screening masses of flavour-SU(3) ground-state JP=0^±, 1^± mesons, and JP=1/2^±, 3/2^± baryons. We find that all correlation channels allowed at T=0 persist when the temperature increases, even above the QCD phase transition. The results for mesons qualitatively agree with those obtained from the contemporary lattice-regularised quantum chromodynamics (lQCD) simulations. One of the most remarkable features is that each parity-partner-pair degenerates when T>Tc, with Tc being the critical temperature. For each pair, the screening mass of the negative parity meson increases monotonously with temperature. In contrast, the screening mass of the meson with positive parity is almost invariant on the domain T\lesssim Tc/2; when T gets close to Tc, it decreases but soon increases again and finally degenerates with its parity partner, which signals the restoration of chiral symmetry. We also find that the T-dependent behaviours of baryon screening masses are quite similar to those of the mesons. For baryons, the dynamical, nonpointlike diquark correlations play a crucial role in the screening mass evolution. We further calculate the evolution of the fraction of each kind of diquark within baryons respective to temperature. We observe that, at high temperatures, only J=0 scalar and pseudoscalar diquark correlations can survive within JP=1/2^± baryons.