Decay-in-Orbit (DIO) Electrons

• For Al, 40% of muons decay “in orbit”

• Free muon decay has end-point of 52.8 MeV

• Nuclear recoil modifies the energy spectrum for DIO

• End-point can reach up to ¹-e conversion energy

• ∝ (E¹-e { E)5 near end-point

• Crucial to understand spectrum near 105 MeV

• New calculations available (autumn 2011)