Relativistic Effects in S-wave Quarkonium Decays
نویسندگان
چکیده
The decay widths of S-wave quarkonia (ηc, ηb → γγ and J/ψ,Υ → ee) are calculated on the basis of a quasipotential approach. The nontrivial dependence on relative quark motion of decay amplitude is taken into consideration via quarkonium wave function. It is shown that relativistic corrections may be large (10-50 %) and comparable with QCD corrections.
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