On total muon capture rates and the average neutrino energy

A method of avoiding the uncertainty associated with the average neutrino energy nu in the usual closure approach to muon capture rates is discussed. Instead of neglecting the kinematic dependence on each particular channel, the partial capture rate is approximated by a first-order expansion around nu . After the sum over the final states is performed, the result is quite independent of the specific value of nu . Application to /sup 3/He, /sup 6/Li and closed-shell nuclei is given, as an effective test of the nuclear models used. (17 refs).