Medium effects and parity doubling of hyperons across the deconfinement phase transition
- Davide DE BONI
We analyse the behaviour of hyperons with strangeness $S=-1,-2$ in the hadronic and quark gluon plasma phases, with particular interest in parity doubling and its emergence as the temperature grows. This study uses our FASTSUM anisotropic $N_f = 2 + 1$ ensembles, with four temperatures below and four above the deconfinement transition temperature, $T_c$. The positive-parity groundstate masses are found to be largely temperature independent below $T_c$, whereas the negative-parity ones decrease considerably as the temperature increases. This may be of interest for heavy-ion phenomenology. Close to the transition, the masses are almost degenerate, in line with the expectation from chiral symmetry restoration. A clear signal of parity doubling is found above $T_c$ for all hyperons, with the strength of the effect depending on the number of $s-$quarks in the baryons.