Comment on "Muon polarization in KL0--> micro micro-bar decay as a test of CP-violation models"

Abstract

The muon longitudinal polarization ${P}_{L}$ in the ${K}^{0}$\ensuremath{\rightarrow}\ensuremath{\mu}\ensuremath{\mu}\ifmmode\bar\else\textasciimacron\fi{} decay in left-right-symmetric models is examined. It is shown that the result crucially depends on the value of neutrino masses. Assuming no arbitrary fine-tuning among the parameters in the neutrino mass matrix, we find that the value of ${P}_{L}$ is less than ${10}^{\mathrm{\ensuremath{-}}3}$.