Abstract: | Formulae for the capture rates, gamma-neutrino correlations, and angular distributions of recoil in muon capture processes Ji Jf by an unpolarized nucleus for Ji ≦ 3 and Jf ≦ 5/2, with and without change of parity of nuclear levels, are given explicitely in terms of the multipole amplitudes. Relation of helicity amplitudes for muonic atom decay to the multipole amplitudes and to amplitudes introduced by other authors is presented. The derivation is based on kinematics only, and the formulae are strictly valid for the muon capture by any nuclei. The formulae are convenient for model calculations of partial transitions with realistic nuclear and muon wave functions and for the phenomenological analysis of a weak interaction. |