An update on the LHC monojet excess

  • Pouya Asadi
  • Matthew R. Buckley
  • Anthony DiFranzo
  • Angelo Monteux
  • David Shih
Open Access
Regular Article - Theoretical Physics


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 H T and requiring the jets to be more central can increase S/B by a factor of ∼1.5.


Phenomenological Models 


Open Access

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Copyright information

© The Author(s) 2018

Authors and Affiliations

  • Pouya Asadi
    • 1
  • Matthew R. Buckley
    • 1
  • Anthony DiFranzo
    • 1
  • Angelo Monteux
    • 1
    • 2
  • David Shih
    • 1
  1. 1.NHETC, Department of Physics and Astronomy, RutgersThe State University of New JerseyPiscatawayU.S.A.
  2. 2.Department of Physics and AstronomyUniversity of California, IrvineIrvineU.S.A.

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