Hyperfine structure and (e−,e+)-pair annihilation in the muonium-positronium MuPs and positronium hydrides

The hyperfine structure splitting of the ground states in a number of positronium hydrides (TPs, DPs, 1HPs) and MuPs (μ+e2−e+) is determined with the use of highly accurate variational wave functions. We evaluate the probabilities of various processes in the MuPs system, including the (e−,e+)-pair annihilation and its conversion into the charge conjugate system μ+e2−e+→μ−e−e2+. Annihilation rates (Γ2γ,Γ3γ,Γ4γ,Γ5γ,…) have also been determined for the ∞HPs, TPs, DPs and 1HPs positronium hydrides.