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arXiv · 2411.10217

Aspects of the chiral crossover transition in (2+1)-flavor QCD with M\"{o}bius domain-wall fermions

Rajiv V. Gavai·Mischa E. Jaensch·Olaf Kaczmarek·Frithjof Karsch·Mugdha Sarkar·Ravi Shanker·Sayantan Sharma·Sipaz Sharma·Tristan Ueding
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Abstract

The non-singlet part of the chiral symmetry in QCD with two light flavors is known to be restored through a crossover transition at a pseudo-critical temperature. However, the temperature dependence of the singlet part of the chiral symmetry and whether it is effectively restored at the same temperature is not well understood. Using (2+1)-flavor QCD configurations generated using the M\"{o}bius domain-wall discretization on an $N_\tau=8$ lattice, we construct suitable observables where the singlet and non-singlet chiral symmetries are disentangled in order to study their temperature dependence across the crossover transition. From the peak of the disconnected part of the chiral susceptibility, we obtain a pseudo-critical temperature $T_{pc}=158.7{}_{{}-2.3}^{{}+2.6}$ MeV where the non-singlet part of the chiral symmetry is effectively restored. From a calculation of the topological susceptibility and its temperature dependence we find that the singlet $U_A(1)$ part of the chiral symmetry is not effectively restored at $T<186$ MeV.

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Rajiv V. Gavai, Mischa E. Jaensch, Olaf Kaczmarek, Frithjof Karsch, Mugdha Sarkar, Ravi Shanker, Sayantan Sharma, Sipaz Sharma, Tristan Ueding. 2024-11-15. Aspects of the chiral crossover transition in (2+1)-flavor QCD with M\"{o}bius domain-wall fermions. https://arxiv.org/abs/2411.10217

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