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arXiv · 1703.09246

Light baryons below and above the deconfinement transition: medium effects and parity doubling

Gert Aarts·Chris Allton·Davide De Boni·Simon Hands·Benjamin Jäger·Chrisanthi Praki·Jon-Ivar Skullerud
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Abstract

We study what happens to the Nucleon, Delta and Omega baryons in the hadronic gas and the quark-gluon plasma, with particular interest in parity doubling and its emergence as the plasma is heated. This is done using simulations of lattice QCD, employing the FASTSUM anisotropic Nf=2+1 ensembles, with four temperatures below and four above the deconfinement transition temperature. Below Tc we find that the positive-parity groundstate masses are largely temperature independent, whereas the negative-parity ones are reduced considerably as the temperature increases. This may be of interest for heavy-ion phenomenology. Close to the transition, the masses are nearly degenerate, in line with the expectation from chiral symmetry restoration. Above Tc we find a clear signal of parity doubling in all three channels, with the effect of the heavier s quark visible.

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Gert Aarts, Chris Allton, Davide De Boni, Simon Hands, Benjamin Jäger, Chrisanthi Praki, Jon-Ivar Skullerud. 2017-03-27. Light baryons below and above the deconfinement transition: medium effects and parity doubling. https://doi.org/10.1007/jhep06(2017)034

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