Analysis of a heavy gluino LSP at CDF: The heavy gluino window

Abstract

In this paper we consider a heavy gluino to be the lightest supersymmetric particle (LSP). We investigate the limits on the mass of a heavy gluino LSP, using the searches for excess events in the jets plus missing momentum channel in run I. The neutral and charged R hadrons, containing a heavy gluino LSP, have distinct signatures at the Fermilab Tevatron. The range of excluded gluino masses depends on whether the R hadron is charged or neutral and the amount of energy deposited in the hadronic calorimeter. The latter depends on the energy loss per collision in the calorimeter and the number of collisions, where both quantities require a model for R-hadron--nucleon scattering. We show how the excluded range of gluino mass depends on these parameters. We find that gluinos with a mass in the range between $\ensuremath{\sim}35$ and $\ensuremath{\sim}115\mathrm{GeV}$ are excluded by CDF run I data. Combined with the previous results of Baer et al., who use CERN LEP data to exclude the range 3 to 22--25 GeV, our result demonstrates that an allowed window for a heavy gluino with a mass between 25 and 35 GeV is quite robust. Finally we discuss the relevant differences of our analysis of Tevatron data to that of Baer et al.