Search for t[¯ overt] Resonances Using Lepton-plus-Jets Events in Proton-Proton Collisions at √s=8 TeV with the ATLAS Detector
Name
JHEP08(2015)148.pdf
Size
1.64 MB
Format
Adobe PDF
Checksum (MD5)
85c0666a9b8abed45e6e83f74c8572e9
Author(s)
Taylor, Frank E
Date Issued
August 2015
Journal
Journal of High Energy Physics
Publisher
Springer Nature
Citation
The ATLAS collaboration, et al. “A Search for t[¯ overt] Resonances Using Lepton-plus-Jets Events in Proton-Proton Collisions at √s=8 TeV with the ATLAS Detector.” Journal of High Energy Physics, vol. 2015, no. 8, Aug. 2015. © 2015 The Authors
Version
Final published version
Abstract
A search for new particles that decay into top quark pairs is reported. The search is performed with the ATLAS experiment at the LHC using an integrated luminosity of 20.3 fb[superscript −1] of proton-proton collision data collected at a centre-of-mass energy of √s=8 TeV. The lepton-plus-jets final state is used, where the top pair decays to W[superscript +]bW[superscript −][¯ over b], with one W boson decaying leptonically and the other hadronically. The invariant mass spectrum of top quark pairs is examined for local excesses or deficits that are inconsistent with the Standard Model predictions. No evidence for a top quark pair resonance is found, and 95% confidence-level limits on the production rate are determined for massive states in benchmark models. The upper limits on the cross-section times branching ratio of a narrow Z′ boson decaying to top pairs range from 4.2 pb to 0.03 pb for resonance masses from 0.4 TeV to 3.0 TeV. A narrow leptophobic topcolour Z′ boson with mass below 1.8 TeV is excluded. Upper limits are set on the cross-section times branching ratio for a broad colour-octet resonance with Γ/m = 15% decaying to t[¯ over t]. These range from 4.8 pb to 0.03 pb for masses from 0.4 TeV to 3.0 TeV. A Kaluza-Klein excitation of the gluon in a Randall-Sundrum model is excluded for masses below 2.2 TeV. Keywords: Exotics, Hadron-Hadron, Scattering Top physics
MIT Department
Massachusetts Institute of Technology. Department of Physics
Terms of Use
Creative Commons Attribution 4.0 International License
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1007/JHEP08(2015)148
