Focus Point SUSY at the LHC Revisited

TL;DR

This paper revisits background estimations for gluino signals in focus point supersymmetry at the LHC, showing that with strong selection criteria, backgrounds are negligible, and that gluino masses up to 2 TeV can be probed with specific tagging strategies.

Contribution

The study extends background analysis by including four third generation quark production and compares different background calculation methods, providing updated gluino mass reach estimates.

Findings

Backgrounds from four third generation quarks are negligible with strong cuts.

Gluino masses close to 2 TeV are accessible with ≥3 b-jet tagging.

Different background estimation methods agree approximately.

Abstract

The estimation of the backgrounds for gluino signals in focus point supersymmetry is extended by including the backgrounds from the production of four third generation quarks in the analysis. We find that these backgrounds are negligible if one uses the strong selection criteria proposed in the literature (including this analysis) for heavy gluino searches. Softer selection criteria often recommended for lighter gluino searches yield backgrounds which are small but numerically significant. We have also repeated the more conventional background calculations and compared our results with the other groups. We find that the size of the total residual background estimated by different groups using different event generators and hard kinematical cuts agree approximately. In view of the theoretical uncertainties in the leading order signal and background cross sections mainly due to the choice of the QCD scale, the gluino mass reach at the LHC cannot be pinpointed. However, requiring a signal with $\rm\geq 3$ tagged b-jets (instead of the standard choice of $\rm\geq 2$) it is shown that gluino masses close to 2 TeV can be probed at the LHC for a range of reasonable choices of the QCD scale for an integrated luminosity of 300 fb$^{-1}$.