Gluino decays with heavier scalar superpartners

Abstract

We compute gluino decay widths in supersymmetric theories with arbitrary flavor and CP violation angles. Our emphasis is on theories with scalar superpartner masses heavier than the gluino such that tree-level two-body decays are not allowed, which is relevant, for example, in split supersymmetry. We compute gluino decay branching fractions in several specific examples and show that it is plausible that the only accessible signal of supersymmetry at the LHC could be four top quarks plus missing energy. We show another example where the only accessible signal for supersymmetry is two gluon jets plus missing energy.hep-ph/0503175

ATLAS Z excess in minimal supersymmetric standard model

“…As studied in refs. [41][42][43][44], the partial decay rate of gluino into a gluon and an (up-type) Higgsino is relatively enhanced by a factor (log (mt/m t )) 2 compared to other channels: (i) gluon and Bino, (ii) neutralino, quark and antiquark, and (iii) chargino, quark and antiquark. Therefore, the gluino efficiently produces Higgsino-like neutralinosχ 0 2 andχ 0 3 in the case of the light gluino and heavy (but relatively lighter among the squarks) stop.…”

“…Because of the renormalization group effects, the right-handed stop is expected to be typically lighter than the other squarks. If the right-handed stop is lighter among the squarks, gluino branching fraction shows an interesting feature: the dominant decay channel becomes the top-stop-loop-induced process into a Higgsino-like neutralino and a gluon for suitable mass splitting between gluino and the neutralinos [41][42][43][44] (see figure 2). This reduces the branching fraction of gluino three-body decay modes, and the gluino dominantly decays into a neutral Higgsino with a gluon.…”

Where the sidewalk ends: jets and missing energy search strategies for the 7 TeV LHC

“…Two bodyg decays to χ 0 and a gluon also appear at loop level in standard supersymmetric theories and can become large when there are sizeable splittings between the left and right handed squarks and can even become the dominant decay mode in split supersymmetric models [50][51][52][53][54][55][56][57][58][59].…”

Large Jet Multiplicities and New Physics at the LHC

“…One can compare the detection prospects for this search strategy with those of other strategies [13,14]. For example, a search for gluino pair-production using the channel with 1 charged lepton and 4 b-tagged jets was estimated to produce a 5σ -sensitivity for Mg as large as 650 GeV with 1 fb −1 of data at 7 TeV [14].…”