The chiral condensate of Nf = 2 + 1 QCD from the spectrum of the staggered Dirac operator

Abstract

We compute the chiral condensate of 2 + 1 QCD from the mode number of the staggered Dirac operator, performing controlled extrapolations to both the continuum and the chiral limit. We consider also alternative strategies, based on the quark mass dependence of the topological susceptibility and of the pion mass, and obtain consistent results within errors. Results are also consistent with phenomenological expectations and with previous numerical determinations obtained with different lattice discretizations.