An update on the LHC monojet excess

Journal Article · 21 March 2018 · Journal of High Energy Physics (Online)

DOI: https://doi.org/10.1007/jhep03(2018)130 · OSTI ID:1502354

Asadi, Pouya ^[1]; Buckley, Matthew R. ^[1]; DiFranzo, Anthony ^[1]; Monteux, Angelo ^[2]; Shih, David ^[1]

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1. Rutgers Univ., Piscataway, NJ (United States). NHETC. Dept. of Physics and Astronomy
2. Rutgers Univ., Piscataway, NJ (United States). NHETC. Dept. of Physics and Astronomy; Univ. of California, Irvine, CA (United States). Dept. of Physics and Astronomy

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.

• Research Organization: Rutgers Univ., Piscataway, NJ (United States); Univ. of California, Irvine, CA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP); National Science Foundation (NSF); Simons Foundation (United States)
• Grant/Contract Number: SC0010008; SC0017811; PHY-1620638; 376204
• OSTI ID: 1502354
• Journal Information: Journal of High Energy Physics (Online), Vol. 2018, Issue 3; ISSN 1029-8479
• Publisher: Springer BerlinCopyright Statement
• Country of Publication: United States
• Language: English