γ rays from muon capture in 27Al and natural Si

Muon capture gamma rays have been observed for the first time in Al-27, and a significant improvement has been made in the identification of gamma-rays from muon capture in natural Si. The (mu(-), nu gamma) reaction was clearly observed in both nuclei and, for Si-28, compares well with calculations. The (mu(-), nu n gamma) reaction was also observed strongly in both nuclei, and the levels which are excited correlate fairly well with the (gamma, p) reaction, but not as well with the spectroscopic factors from the (d, He-3) reaction. Some (mu(-), nu 2n gamma), (mu(-), nu 3n gamma), (mu(-), nu p gamma), (mu(-), nu pn gamma), and other reactions have been observed at a lower yield. The Lyman series of the muonic x ray cascades have also been studied.