Renormalization of Chiral Perturbation Theory to Order p6

The renormalization of chiral perturbation theory is carried out to next-to-next-to-leading order in the meson sector. We calculate the divergent part of the generating functional of Green functions of quark currents to O(p⁶) for chiral SU(n), involving one- and two-loop diagrams. The renormalization group equations for the renormalized low-energy constants of O(p⁶) are derived. We compare our results with previous two-loop calculations in chiral perturbation theory.