Interpreting a CMS $lljj{p}_T^{\mathrm{miss}}$ Excess With the Golden Cascade of the MSSM

Abstract

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: $\tilde{q}\to {\tilde{\chi }}_2^{0}q\to \tilde{l}lq\to {\tilde{\chi }}_1^{0}qll$ 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 $p_T^{\mathrm{miss}}$, rule out all of the remaining parameter space at the 95% CL.

Comments: 7 pages, 11 figures, v2 fixes problem with axis of Fig. 1 and has some minor changes to text, v3 is a significant revision including new LHC searches which rules out the golden channel interpretation at 95$\%$ confidence level, v4 corrects a mistake in the axis labels on some figures