A model-independent expression for the Dalitz plot of semileptonic decays of neutral kaons, $K_{l3}^0$, including radiative corrections to order $(\alpha /\pi )(q/M_1)$, where $q$ is the momentum transfer and $M_1$ is the mass of the kaon, is presented. The model dependence of radiative corrections is kept in a general form within this approximation, which is suitable for model-independent experimental analyses. Expressions for bremsstrahlung radiative corrections are presented in two forms: one with the triple integral over the kinematical variables of the photon ready to be performed numerically and the other one in a fully analytical form. The final result is restricted to the so-called three-body region of the Dalitz plot and it is not compromised to fixing the values of the form factors at predetermined values.

• Received 26 July 2015

DOI:https://doi.org/10.1103/PhysRevD.92.074022