Sterile neutrino and leptonic decays of the pseudoscalar mesons

We consider a scenario with only one sterile neutrino $N$, negligible mixing with the active neutrinos ${\nu }_L$, where its interactions with ordinary particles could be described in a model independent approach based on an effective theory. Under such a framwork, we consider the contributions of the sterile neutrino $N$ to the pure leptonic decays $M\to l\nu$ and $\nu \bar{\nu }$, and the radiative leptonic decays $ M \rightarrow l\nu\gamma $with$M$denotingthepseudoscalarmesons$ B $,$ D $and$ K$. We find that it can produce significant effects on some of these rare decay processes.