NLO CHPT corrections to the transverse muon polarization in $K_{l2\gamma}$ decay

Abstract

The calculation of the transverse muon polarization in $K^+ \to \mu^+ \nu \gamma$ decay due to the final state interaction up to $O(p^6)$ CHPT level has been carried out. It is shown that $O(p^6)$ corrections to the observable is much less than $O(p^4)$ contribution.