Curvature of the chiral pseudocritical line in QCD: Continuum extrapolated results

Abstract

We determine the curvature of the pseudocritical line of strong interactions by means of numerical simulations at imaginary chemical potentials. We consider ${N}_{f}=2+1$ stout improved staggered fermions with physical quark masses and the tree level Symanzik gauge action, and explore four different sets of lattice spacings, corresponding to ${N}_{t}=6,8,10,12$, in order to extrapolate results to the continuum limit. Our final estimate is $\ensuremath{\kappa}=0.0135(20)$.