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arXiv · 2301.03952

Determination of Lee-Yang edge singularities in QCD by rational approximations

Kevin Zambello·David A. Clarke·Petros Dimopoulos·Francesco Di Renzo·Jishnu Goswami·Guido Nicotra·Christian Schmidt·Simran Singh
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Abstract

We report updated results on the determination of Lee-Yang edge (LYE) singularities in $N_f = 2+1$ QCD using highly improved staggered quarks (HISQ) with physical masses on $N_\tau = 4, 6, 8$ lattices. The singularity structure of QCD in the complex $\mu_B$ plane is probed using conserved charges calculated at imaginary $\mu_B$. The location of the singularities is determined by studying the (uncancelled) poles of multi-point Pad\'e approximants. We show that close to the Roberge-Weiss (RW) transition, the location of the LYE singularities scales according to the $3$-$d$ $Z(2)$ universality class. By combining the new $N_\tau = 6$ data with the $N_\tau = 4$ data from our previous analysis we extract a rough estimate for the RW temperature in the continuum limit. We also discuss some preliminary results for the singularities close to the chiral phase transition obtained from simulations on $N_\tau = 6, 8$ lattices.

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Kevin Zambello, David A. Clarke, Petros Dimopoulos, Francesco Di Renzo, Jishnu Goswami, Guido Nicotra, Christian Schmidt, Simran Singh. 2023-01-10. Determination of Lee-Yang edge singularities in QCD by rational approximations. https://doi.org/10.22323/1.430.0164

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