Two schemes ofη−η′-mixing

Abstract

Proceeding from the expansion of composite operators in interpolating hadronic fields, the width of the decays η(η′)→γγ andJ/ψ→η(η′)γ have been calculated. Two mechanisms of pseudoscalar field mixing (“mass-mixing” and “current-mixing”) are considered. In the given schemes, the values of η−η′-mixing angle θ _p are, respectively, (−15.0±1.8)^o and (−19.7±2.2)^o.