Supersymmetry at a proposed √s =4 TeV upgrade of the Fermilab Tevatron

We study the signals for supersymmetry at the Fermilab Tevatron and its proposed energy upgrade (called the DiTevatron here) (√s =4 TeV) in various well-motivated supersymmetric models. We consider the trilepton signature in the decay of pair-produced charginos and neutralinos, the missing energy signature in gluino and squark production, and the b bar b signal in the decay of the lightest supersymmetric Higgs boson produced in association with a W or Z boson. In each case we perform signal and background studies, using Monte Carlo and/or real data to estimate the sensitivity to these signals at the Tevatron and DiTevatron with the Main Injector, for short- and long-term integrated luminosities of scrL=10 and 25 fb-1, and 5σ statistical significance. We conclude that one could probe chargino masses as high as mχ1±∼180 (200) GeV, gluino masses as high as mg∼450 (750) GeV, and lightest Higgs boson masses as high as mh∼110 (120) GeV at the Tevatron (DiTevatron). A high-luminosity option at the Tevatron (1033 cm-2 s-1) may compensate somewhat for the higher reach of the DiTevatron, but only in the trilepton and Higgs signals. However, these gains may be severely compromised once the multiple-interaction environment of the high-luminosity Tevatron is accounted for