Radiative corrections in K --> pi l+ l- decays

TL;DR

This paper calculates radiative corrections for K --> pi l+ l- decays, highlighting the soft-photon approximation's effectiveness for muons and the need for phase space cuts with electrons, with implications for related decays.

Contribution

It provides detailed radiative correction calculations for kaon decays and discusses their application to similar processes involving eta and omega decays.

Findings

Soft-photon approximation works well for muon channels.

Phase space cuts are necessary for electron channels.

Results can be transferred to eta and omega decay processes.

Abstract

We calculate radiative corrections to the flavor-changing neutral current process K --> pi l+ l-, both for charged and neutral kaon decays. While the soft-photon approximation is shown to work well for the muon channels, we discuss the necessity of further phase space cuts with electrons in the final state. It is also shown how to transfer our results to other decays such as eta --> gamma l+ l- or omega --> pi0 l+ l-.