New constraints on R-parity violation from K and B systems

Abstract

We have derived new upper limits on several products (two at a time) of lepton number violating ${\lambda }^{\prime }$-type couplings from the consideration of $\Delta S=2$ and $\Delta B=2$ box graphs. Each box contains one scalar lepton and one W-boson or one charged-Higgs-boson as internal lines. Most of these bounds are more stringent than previously obtained. Some of these product couplings drive $K_L$ (and some other $B_d$) decays to two charged leptons at enhanced rates. Some of them can explain the rare $K^{+}\to {\pi }^{+}\nu \bar{\nu }$ event recently observed at BNL.

Comments: Latex, 6 pages, no figures; revised and published version with minor changes in the Table caption and a few cosmetic changes in the text