Wave functions and annihilation widths of heavy quarkonia

Within the framework of nonrelativistic quark-antiquark Cornell potential model formalism, we study the annihilation of heavy quarkonia. We determine their annihilation widths resulting into $gammagamma$, $gg$, $3gamma$, $3g$ and $gamma gg$ and compare our findings with the available theoretical results and experimental data. We also provide the charge radii and absolute square of radial Schrodinger wave function at zero quark-antiquark separation.