NLSP Gluino Search at the Tevatron and early LHC

TL;DR

This paper explores a new search strategy for nearly degenerate gluino-bino pairs in supersymmetric models at the Tevatron and early LHC, focusing on multi-b final states from gluino decay.

Contribution

It introduces a novel search method for NLSP gluino involving multi-b final states, applicable to models with nearly degenerate gluino and bino masses.

Findings

Potential for 4.5 sigma detection at Tevatron with 10 fb^{-1}

Approximately 10 signal events at 7 TeV LHC with 50 pb^{-1}

Gluino mass around 300 GeV with dominant three-body decay

Abstract

We investigate the collider phenomenology of gluino-bino co-annihilation scenario both at the Tevatron and 7 TeV LHC. This scenario can be realized, for example, in a class of realistic supersymmetric models with non-universal gaugino masses and t-b-\tau Yukawa unification. The NLSP gluino and LSP bino should be nearly degenerate in mass, so that the typical gluino search channels involving leptons or hard jets are not available. Consequently, the gluino can be lighter than various bounds on its mass from direct searches. We propose a new search for NLSP gluino involving multi-b final states, arising from the three-body decay \tilde{g}-> b\bar{b}\tilde{\chi}_1^0. We identify two realistic models with gluino mass of around 300 GeV for which the three-body decay is dominant, and show that a 4.5 \sigma observation sensitivity can be achieved at the Tevatron with an integrated luminosity of 10 fb^{-1}. For the 7 TeV LHC with 50 pb^{-1} of integrated luminosity, the number of signal events for the two models is O(10), to be compared with negligible SM background event.