出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We study the correction to the radiativep 0 decay width due to finite light quarkmass. Using lattice QCD with the overlap fermion formulation, we calculate the three-point function of the form hPVmVn i in the (Euclidean) momentum space, which corresponds to the p 0 !g g amplitude. To fit the lattice data, we use two different modifications of vector meson dominance (VMD) ansatz. One is a combined form of VMD with the next-to-leading order (NLO) chiral perturbation theory (ChPT), and the other is a resummed form of pion-loop diagrams. We extract one of the low energy constants in NLO ChPT, and estimate p 0 !gg decay width including finite mass correction.
