Non-standard neutrino interactions in K^{+}\to\pi^{+}\nu\bar{\nu} and D^{+}\to\pi^{+}\nu\bar{\nu} decays

Abstract

We study the contributions of the non-standard neutrino interactions (NSIs) to the rare meson decays of $K^{+}\to {\pi }^{+}\nu \bar{\nu }$ and $D^{+}\to {\pi }^{+}\nu \bar{\nu }$. We show that both decays could provide strong constraints on the free parameters in the NSIs. We point out that the branching ratio of $D^{+}\to {\pi }^{+}\nu \bar{\nu }$ could be at the level of $10^{-8}$.

Comments: 7 pages and 2 figures, reference added, version to appear in Phys. Rev. D