Download or read book Two Photon Decays of Charmonia from Lattice QCD. written by and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: 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 sum of hadronic vector eigenstates, we compute form-factors in both the space-like and time-like domains for the transitions [eta]{sub c} → [gamma]*[gamma]* and [chi]{sub c0} → [gamma]*[gamma]*. At the on-shell point we find approximate agreement with experimental world-average values.