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arXiv · 1502.03603

Nucleons and parity doubling across the deconfinement transition

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

It is expected that nucleons and their parity partners become degenerate when chiral symmetry is restored. We investigate this question in the context of the thermal transition from the hadronic phase to the quark-gluon plasma, using lattice QCD simulations with N_f=2+1 flavours. We observe a clear sign of parity doubling in the quark-gluon plasma. Besides, we find that the nucleon ground state is, within the uncertainty, largely independent of the temperature, whereas temperature effects are substantial in the negative-parity (N^*) channel, already in the confined phase.

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Gert Aarts, Chris Allton, Simon Hands, Benjamin Jäger, Chrisanthi Praki, Jon-Ivar Skullerud. 2015-02-12. Nucleons and parity doubling across the deconfinement transition. https://doi.org/10.1103/physrevd.92.014503

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