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Register a new userInterpreting a CMS $lljjp_T^{rm miss}$ Excess With the Golden Cascade of the MSSM
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The CMS experiment recently reported an excess consistent with an invariant mass edge in opposite-sign same flavor (OSSF) leptons, when produced in conjunction with at least two jets and missing transverse momentum. We provide an interpretation of the edge in terms of (anti-)squark pair production followed by the `golden cascade decay for one of the squarks: $tilde q rightarrow tildechi_2^0 q to tilde l l q to tildechi_1^0 q l l$ in the minimal supersymmetric standard model (MSSM). A simplified model involving binos, winos, an on-shell slepton, and the first two generations of squarks fits the event rate and the invariant mass edge. We check consistency with a recent ATLAS search in a similar region, finding that much of the good-fit parameter space is still allowed at the 95% confidence level (CL). However, a combination of other LHC searches, notably two-lepton stop pair searches and jets plus $p_T^{rm miss}$, rule out all of the remaining parameter space at the 95% CL.
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