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arXiv · 1805.02960

Curvature of the pseudocritical line in QCD: Taylor expansion matches analytic continuation

Claudio Bonati·Massimo D'Elia·Francesco Negro·Francesco Sanfilippo·Kevin Zambello
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Abstract

We determine the curvature of the pseudo-critical line of $N_f = 2 + 1$ QCD with physical quark masses via Taylor expansion in the quark chemical potentials. We adopt a discretization based on stout improved staggered fermions and the tree level Symanzik gauge action; the location of the pseudocritical temperature is based on chiral symmetry restoration. Simulations are performed on lattices with different temporal extent ($N_t = 6, 8, 10$), leading to a continuum extrapolated curvature $κ= 0.0145(25)$, which is in very good agreement with the continuum extrapolation obtained via analytic continuation and the same discretization, $κ= 0.0135(20)$. This result eliminates the possible tension emerging when comparing analytic continuation with earlier results obtained via Taylor expansion.

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Claudio Bonati, Massimo D'Elia, Francesco Negro, Francesco Sanfilippo, Kevin Zambello. 2018-05-08. Curvature of the pseudocritical line in QCD: Taylor expansion matches analytic continuation. https://doi.org/10.1103/physrevd.98.054510

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