High-precision muon decay predictions for ALP searches

P. Banerjee, A. M. Coutinho, T. Engel +3

We present an improved theoretical prediction of the positron energy spectrum for the polarised Michel decay ${\mu }^{+}\to e^{+}{\nu }_e{\bar{\nu }}_{\mu }$. In addition to the full next-to-next-to-leadin…