New constraints on<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>R</mml:mi></mml:math>-parity violation from<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>K</mml:mi></mml:math>and<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>B</mml:mi></mml:math>systems

We derive new upper limits on several products (two at a time) of lepton number violating ${\ensuremath{\lambda}}^{\ensuremath{'}}$-type couplings from the consideration of $\ensuremath{\Delta}S=2$ and $\ensuremath{\Delta}B=2$ 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 ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}\ensuremath{\nu}\overline{\ensuremath{\nu}}$ event recently observed at BNL.

Not yet translated