The rate of the radiative decay of the HeH+(b (3) Sigma(+)) molecular
ion has been investigated. At infinite internuclear separation the b (
3) Sigma(+) electronic state dissociates to form metastable atomic hel
ium He(2 S-3) and a proton H+. The optically allowed electronic transi
tion to the lowest triplet HeH+(a (3) Sigma(+)) state which dissociate
s to He+(1s) and H(1s) was considered. This transition can lead to the
population of metastable triplet (a (3) Sigma(+)) states in beams of
HeH+ ions.