Masses and decay rates of charmonia

The heavy flavored mesons spectroscopy is now interesting and challenging due to number states observed experimentally and their possible theoretical explanation as mesons, baryons and exotic states. Charmonia are charmed quark and its anti-quark (cc-bar) system belong to a heavy flavor mesons. Properties like mass spectra and radiative decays are influenced by relativistic effects. The mass spectra of charmonia (such as η_c, J/ψ or ψ) are calculated in the framework of quark model using relativistic correction to the kinetic energy term. We also calculate the decay widths with in nonrelativistic QCD (NRQCD) approach