Muon transfer in d mu+H-2 collisions

The impact of excited state muon transfer in d mu + H-2 collisions has been investigated. The formation of metastable pd mu(*) molecules and their sub sequent decay into the p mu (1s) + d channel opens a transfer channel that is otherwise closed at the n=2 level. This mechanism enlarges the fraction of muons arriving to the ground state of the lighter isotope. The resulting ground state population P-1s(p mu) as function of deuterium concentration appears to be in qualitative agreement with recent measurements of the K-al pha X-ray yield in H-2/D-2 mixtures.