Possible sneutrino-pair signatures with R-parity breaking

Abstract

If sneutrinos are the lightest supersymmetry partners and $R$-parity is not conserved, the process $e^{+}{e}^{-}\to \widetilde{\stackrel{ˉ}{\hat{I}}½}\tilde{\hat{I}}½$ can have striking signatures due to the decay modes $\tilde{\hat{I}}½\to {\ell }^{+}{\ell }^{\prime -}$ or $\tilde{\hat{I}}½\to q{\bar{q}}^{\prime }$. We present cross section formulas and discuss event rates and detection at the upgraded $e^{+}{e}^{-}$ collider LEP. Four-lepton signals should be detectable up to sneutrino mass ${\tilde{m}}_{\hat{I}}½=80$ GeV and maybe beyond; four-jet signals should be detectable up to ${\tilde{m}}_{\hat{I}}½=70$ GeV, but would probably be obscured thereafter by $WW$ background.

standard Latex, 9 pages, 2 uufiled postscript figures included via figures command. Compressed postscript version with figures available at http://phenom.physics.wisc.edu/pub/preprints/1995/madph-95-903.ps.Z or ftp://phenom.physics.wisc.edu/pub/preprints/1995/madph-95-903.ps.Z