Probing parity doubling in nucleons at high temperature

TL;DR

This study investigates how nucleons and their parity partners behave across the deconfinement transition, showing evidence of parity doubling and chiral symmetry restoration in the high-temperature phase.

Contribution

It provides the first detailed analysis of parity doubling in nucleons at high temperature using multiple correlation function techniques.

Findings

Degeneracy of parity partners in the deconfined phase

Nucleon ground state remains stable in the hadronic phase

Significant temperature effects observed in negative parity channel

Abstract

The spectrum of nucleons and their parity partners is studied as a function of temperature spanning the deconfinement transition. We analyse our results using the correlation functions directly, exponential fits in the hadronic phase, and the Maximum Entropy Method. These techniques all indicate that there is degeneracy in the parity partners' channels in the deconfined phase. This is in accordance with the expectation that there is parity doubling and chiral symmetry in the deconfined phase. In the hadronic phase, we also find that the nucleon ground state is largely independent of temperature, whereas there are substantial temperature effects in the negative parity channel. All results are obtained using our FASTSUM 2+1 flavour ensembles.