Non-perturbative renormalization of bilinear operators with dynamical overlap fermions

Understand

Using the non-perturbative renormalization technique, we calculate the renormalization factors for quark bilinear operators made of overlap fermions on the lattice.

• The background gauge field is generated by the JLQCD and TWQCD collaborations including dynamical effects of two or 2+1 flavors of light quarks on a 16$^3\times$32 or 16$^3\times$48 lattice at lattice spacing around 0.1 fm.
• By reducing the quark mass close to the chiral limit, where the finite volume system enters the so-called $\epsilon$-regime, the unwanted effect of spontaneous chiral symmetry breaking on the renormalization factors is suppressed.
• On the lattices in the conventional $p$-regime, this effect is precisely subtracted by separately calculating the contributions from the chiral condensate.