Signals of a Sneutrino (N)LSP at the LHC

Abstract

The sneutrino is a viable candidate for the NLSP in SUSY spectra with gravitino LSP. In this work we study the collider implications of this possibility. In particular, we investigate whether the LHC can distinguish it (at least, in some cases) from alternative spectra, such as those with a neutralino LSP. We show that there exists a complete family of experimentally allowed and theoretically motivated spectra with sneutrino NLSP, which exhibit very distinctive multilepton signals that are difficult to fake within the MSSM. We study these signals in detail, including the techniques necessary to find them. We demonstrate our analysis approach on simulations incorporating backgrounds.Comment: 41 pages, 13 figures. V2: Tau-tau background added and background discussion in subsection V.C modified. Short discussion about early discovery in subsection V.D added. Minors changes and refs. adde