We make the first calculation in lattice QCD of two-photon decays of mesons. Working in the charmonium sector, using the LSZ reduction to relate a photon to a s

Charmonium is an attractive system for the application of lattice QCD methods owing to the possibility of computing with the physical quark mass in a reasonable

Charmonium is an attractive system for the application of lattice QCD methods. While the sub-threshold spectrum has been considered in some detail in previous w