Search for new phenomena in a lepton plus high jet multiplicity final state with the ATLAS experiment using √s=13 TeV proton-proton collision data

Date

2017

Authors

Aaboud, M.
Albert, Justin
Chiu, Y. H.
Elliot, Alison A.
Fincke-Keeler, J.
Hamano, Kenji
Hill, Ewan Chin
Keeler, Richard
Kowalewski, Robert
Kuwertz, E. S.

Journal Title

Journal ISSN

Volume Title

Publisher

Journal of High Energy Physics

Abstract

A search for new phenomena in final states characterized by high jet multiplicity, an isolated lepton ( electron or muon) and either zero or at least three b-tagged jets is presented. The search uses 36.1 fb(-1) of root s = 13TeV proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider in 2015 and 2016. The dominant sources of background are estimated using parameterized extrapolations, based on observables at medium jet multiplicity, to predict the b-tagged jet multiplicity distribution at the higher jet multiplicities used in the search. No significant excess over the Standard Model expectation is observed and 95% confidence-level limits are extracted constraining four simplified models of R-parity-violating supersymmetry that feature either gluino or top-squark pair production. The exclusion limits reach as high as 2.1TeV in gluino mass and 1.2TeV in top-squark mass in the models considered. In addition, an upper limit is set on the cross-section for Standard Model t (t) over bart (t) over bar production of 60 fb (6.5 x the Standard Model prediction) at 95% confidence level. Finally, model-independent limits are set on the contribution from new phenomena to the signal-region yields.

Description

Keywords

Beyond Standard Model, Hadron-Hadron scattering (experiments)

Citation

Aaboud, M.; Aad, G.; Abbott, B.; Abdinov, O.; Abeloos, B.; Abidi, S. H.; … & Zwalinski, L. (2017). Search for new phenomena in a lepton plus high jet multiplicity final state with the ATLAS experiment using √s=13 TeV proton-proton collision data. Journal of High Energy Physics, 2017(9), article 88. DOI: 10.1007/JHEP09(2017)088