Cross section of the Coulomb excitation of $^{229m}$Th by low energy muons

Abstract

The inelastic scattering cross section for muons, µ − , with energies E=9-100 eV from the 229 Th nuclei is calculated in the framework of the second order of the perturbation theory for the quantum electrodynamics. The dominant contribution to the excitation of the low energy isomer 229m Th(3/2 + , 8.19 ± 0.12 eV) comes from the E2 multipole. The excitation cross section reaches the value of 10 −21 cm 2 in the range E ≈10 eV. This is four to five orders of magnitude larger than the electron excitation cross section and enough for efficient excitation of 229m Th on the muon beam at the next generation of muon colliders.