New Production Mechanism of Neutral Higgs Bosons with Right scalar tau neutrino as the LSP

Abstract

Motived by the neutrino oscillation data, we consider the lightest tau sneutrino $\tilde \nu_{\tau_1}$ (which is mostly the right tau sneutrino) to be the lightest supersymmetric particle (LSP) in the framework of the minimal supersymmetric Standard Model. Both the standard and the non-standard trilinear scalar coupling terms are included for the right tau sneutrino interactions. The decay branching ratio of $\tilde \nu_{\tau_2} \to \tilde \nu_{\tau_1}+ h^0$ can become so large that the production rate of the lightest neutral Higgs boson ($h^0$) can be largely enhanced at electron or hadron colliders, either from the direct production of $\tilde \nu_{\tau_2}$ or from the decay of charginos, neutralinos, sleptons, and the cascade decay of squarks and gluinos, etc. Furthermore, because of the small LSP annihilation rate, $\tilde \nu_{\tau_1}$ can be a good candidate for cold dark matter.