Medium effects and parity doubling of hyperons across the deconfinement phase transition*
Department of Physics, College of Science, Swansea University, Swansea SA2 8PP, United Kingdom
2 ETH Zürich, Institute for Theoretical Physics, Wolfgang-Pauli-Str. 27, 8093 Zürich, Switzerland
3 Danish Institute for Advanced Study and CP3-Origins, Department of Mathematics and Computer Science, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark
4 Department of Theoretical Physics, Maynooth University, County Kildare, Ireland
5 School of Mathematics, Trinity College Dublin, Dublin 2, Ireland
** Speaker, e-mail: firstname.lastname@example.org
Published online: 26 March 2018
We analyse the behaviour of hyperons with strangeness S = –1,–2,–3 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 Nf = 2+1 ensembles, with four temperatures below and four above the deconfinement transition temperature, Tc. The positive-parity groundstate masses are found to be largely temperature independent below Tc, whereas the negative-parity ones decrease considerably as the temperature increases. Close to the transition, the masses are almost degenerate, in line with the expectation from chiral symmetry restoration. This may be of interest for heavy-ion phenomenology. In particular we show an application of this effect to the Hadron Resonance Gas model. A clear signal of parity doubling is found above Tc in all hyperon channels, with the strength of the effect depending on the number of s-quarks in the baryons.
© The Authors, published by EDP Sciences, 2018
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