Curvature of the chiral pseudo-critical line in QCD

Understand

We determine the curvature of the pseudo-critical 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 two different sets of lattice spacings, corresponding to temporal extensions $N_t = 6$ and $N_t = 8$.
• Both the renormalized chiral condensate and the renormalized chiral susceptibility are used to locate the transition.
• The determinations obtained from the two quantities are in good agreement, a preliminary continuum extrapolation yields $\kappa = 0.013(2)(1)$.