Abstract
In previous work, we identified an anomalous number of events in the LHC jets+MET searches characterized by low jet multiplicity and low-to-moderate transverse energy variables. Here, we update this analysis with results from a new ATLAS search in the monojet channel which also shows a consistent excess. As before, we find that this “monojet excess” is well-described by the resonant production of a heavy colored state decaying to a quark and a massive invisible particle. In the combined ATLAS and CMS data, we now find a local (global) preference of 3.3σ (2.5σ) for the new physics model over the Standard Model-only hypothesis. As the signal regions containing the excess are systematics-limited, we consider additional cuts to enhance the signal-to-background ratio. We show that binning finer in HT and requiring the jets to be more central can increase S/B by a factor of ∼1.5.
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ArXiv ePrint: 1712.04939
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Asadi, P., Buckley, M.R., DiFranzo, A. et al. An update on the LHC monojet excess. J. High Energ. Phys. 2018, 130 (2018). https://doi.org/10.1007/JHEP03(2018)130
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DOI: https://doi.org/10.1007/JHEP03(2018)130