Detecting gluinos at hadron supercolliders

Abstract

If the gluino mass exceeds 150–200 GeV, searches for gluinos will likely have to be made at multi-TeV hadron colliders. Unlike the case of light gluinos ($m_{g̃}$≲60 GeV), which dominantly decay via g̃→qq¯γ̃, heavy-gluino decays proceed via g̃→qq¯W${̃}_i$ and g̃→qq¯Z${̃}_j$ where W${̃}_i$ and Z${̃}_j$ are charged and neutral mass eigenstates in the gauge-Higgs-fermion sector. The usual missing-$p_T$ signatures are altered and new strategies may be required for gluino detection. We analyze heavy-gluino and scalar-quark decays and estimate the production rates for W${̃}_i$W${̃}_j$, W${̃}_i$Z${̃}_j$, and Z${̃}_i$Z${̃}_j$ pairs at a 40-TeV pp collider. Since a heavy gluino decays dominantly into jets and the heavy chargino, which in turn decays into a $Z^0$ or W boson plus a lighter chargino or neutralino, a typical gluino-pair event contains several leptons and/or jets in the final state.