  We calculate the chiral condensate of QCD with 2, 2+1 and 3 flavors of sea
quarks. Lattice QCD simulations are performed employing dynamical overlap
fermions with up and down quark masses covering a range between 3 and 100 MeV.
On L ~ 1.8-1.9 fm lattices at a lattice spacing ~ 0.11 fm, we calculate the
eigenvalue spectrum of the overlap-Dirac operator. By matching the lattice data
with the analytical prediction from chiral perturbation theory at the
next-to-leading order, the chiral condensate in the massless limit of up and
down quarks is determined.

High Energy Physics - Lattice;High Energy Physics - Phenomenology