Muon capture by ³He nuclei followed by proton and deuteron production

The paper describes an experiment aimed at studying muon capture by ³He nuclei in pure ³He and D₂+³He mixtures at various densities. Energy distributions of protons and deuterons produced via μ^-+³He→p+n+n+ν_μ and μ^-+³He→d+n+ν_μ are measured for the energy intervals 10–49 MeV and 13–31 MeV, respectively. Muon capture rates λ_cap^p(ΔE_p) and λ_cap^d(ΔE_d) are obtained using two different analysis methods. The least-squares methods give λ_cap^p=(36.7±1.2)s^-1, λ_cap^d=(21.3±1.6)s^-1. The Bayes theorem gives λ_cap^p=(36.8±0.8)s^-1, λ_cap^d=(21.9±0.6)s^-1. The experimental differential capture rates, dλ_cap^p(E_p)/dE_p and dλ_cap^d(E_d)/dE_d, are compared with theoretical calculations performed using the plane-wave impulse approximation with the realistic nearest-neighbor interaction Bonn B potential. Extrapolation to the full energy range yields total proton and deuteron capture rates in good agreement with former results.