Searching for NLSP Sbottom at the LHC

Abstract

We study the collider phenomenology of sbottom-bino co-annihilation scenario at both the 7 TeV and 14 TeV LHC. This co-annihilation scenario requires that the NLSP sbottom and LSP bino masses are apart by no more than about 20% or so, and for M_{\tilde{b}_1}>M_b+M_{\tilde{\chi}_1^0}, the sbottom decays exclusively into b+\tilde{\chi}_1^0. We propose a search for sbottom pairs through b\bar{b} plus missing energy. By scanning the mass parameters M_{\tilde{b}_1} and M_{\tilde{\chi}_1^0}, we investigate the discovery limits of sbottom and bino in the M_{\tilde{b}_1}-M_{\tilde{\chi}_1^0} plane with at least 5\sigma significance at the LHC, for varying integrated luminosities. It is shown that with at least 5 fb^{-1} luminosity, the 7 TeV LHC can explore a narrow region satisfying the 20% co-annihilation condition. For the 14 TeV LHC with 10 (100) fb^{-1} luminosity, the discovery limit of M_{\tilde{b}_1} is 360 (570) GeV.