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arXiv · 2405.10196

Searching for the QCD critical endpoint using multi-point Pad\'e approximations

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

Using the multi-point Pad\'e approach, we locate Lee-Yang edge singularities of the QCD pressure in the complex baryon chemical potential plane. These singularities are extracted from singularities in the net baryon-number density calculated in $N_f=2+1$ lattice QCD at physical quark mass and purely imaginary chemical potential. Taking an appropriate scaling ansatz in the vicinity of the conjectured QCD critical endpoint, we extrapolate the singularities on $N_\tau=6$ lattices to pure real baryon chemical potential to estimate the position of the critical endpoint (CEP). We find $T^{\rm CEP}=105^{+8}_{-18}$~ MeV and $\mu_B^{\rm CEP} = 422^{+80}_{-35}$~ MeV, which compares well with recent estimates in the literature. For the slope of the transition line at the critical point we find $-0.16(24)$.

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David A. Clarke, Petros Dimopoulos, Francesco Di Renzo, Jishnu Goswami, Christian Schmidt, Simran Singh, Kevin Zambello. 2024-05-16. Searching for the QCD critical endpoint using multi-point Pad\'e approximations. https://arxiv.org/abs/2405.10196

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