Muon- and Pion-Induced Fission of Uranium Isotopes

Abstract

We have measured the energy distributions of fission fragments following formation of muonic and pionic $^{233}\mathrm{U}$ and $^{235}\mathrm{U}$. We have confirmed earlier results on the mean lives for muon capture by $^{235}\mathrm{U}$ and $^{238}\mathrm{U}$ and extended the study to $^{233}\mathrm{U}$. Additional data have also been obtained on the process whereby a muon induces fission by transferring its excitation energy to the nucleus in a radiationless transition to the $1s$ level.