On the LHC observation of gluinos from the Egret-preferred region

Abstract

Prospects for observation of a SUSY-like signal from two gluinos $$ \tilde g\tilde g $$ are investigated within a certain region of the mSUGRA parameter space, where the cross section of the two-gluino production in pp-collisions at the LHC ( $$ \sqrt s $$ = 14 TeV) is estimated at a rather high level of 17.3 pb. In this so-called EGRET-preferred region, the lightest stable neutralinos χ 1 0 can serve as cold-dark-matter particles and can naturally explain the excess of diffuse Galactic gamma rays observed by the EGRET space apparatus. The $$ \tilde g\tilde g $$ -event selection relies on a clear signature when decay products of each gluino contain one b $$ \bar b $$ pair, one or two l $$ \bar l $$ pair(s) or one or two light q $$ \bar q $$ pair(s), and a neutralino. Rather high transverse missing energy carried away by the two neutralinos is the essential signature of the events using of which allows the relevant Standard Model background to be reduced significantly. Furthermore, distributions of the reconstructed invariant masses of two opposite-charged-lepton or light-jet pairs produced by the χ 2 0 → χ 1 0 l + l − and χ 2 0 → χ 1 0 q $$ \bar q $$ three-body decays have kinematic end points which measure the difference between masses of χ 2 0 and χ 1 0 . In particular, it was found that these signatures of selected processes demonstrate good prospects for discovery of gluinos at the LHC. These signatures allow one to distinguish different mSUGRA parameters m 1/2 within the EGRET-preferred region (at a higher than 6σ confidence level with 300 fb−1 data).