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arXiv · 2102.09916

Screening masses towards chiral limit

Simon Dentinger·Olaf Kaczmarek·Anirban Lahiri
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Abstract

A possible effective restoration of the anomalous $U_A(1)$ symmetry would have a non-trivial effect on the global phase diagram of QCD. In this work we investigate the effective restoration of the $U_A(1)$ through the calculation of scalar and pseudo-scalar screening masses and corresponding susceptibilities, for physical and lower than physical pion masses. Calculations have been performed in (2+1)-flavor HISQ discretization scheme with a physical value of the strange quark mass. Preliminary calculations of the continuum extrapolated scalar and pseudo-scalar masses are presented, based on lattices with three different temporal extent. Non-trivial structure of the difference between scalar and pseudo-scalar susceptibilites are discussed for $N_\tau=8$ lattices.

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Simon Dentinger, Olaf Kaczmarek, Anirban Lahiri. 2021-02-19. Screening masses towards chiral limit. https://doi.org/10.5506/aphyspolbsupp.14.321

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