A Search for tt̅ Resonances Using Lepton-Plus-Jets Events in Proton-Proton Collisions at √s=8 TeV with the ATLAS Detector

DSpace/Manakin Repository

A Search for tt̅ Resonances Using Lepton-Plus-Jets Events in Proton-Proton Collisions at √s=8 TeV with the ATLAS Detector

Show full item record

Title: A Search for tt̅ Resonances Using Lepton-Plus-Jets Events in Proton-Proton Collisions at √s=8 TeV with the ATLAS Detector
Author(s):
Aad, G.;
Abbott, B.;
Abdallah, J.;
Abdinov, O.;
Aben, R.;
Abolins, M.;
AbouZeid, O. S.;
ATLAS Collaboration
Item Type: article
Keywords: Show Keywords
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(-1) of proton-proton collision data collected at a centre-of-mass energy of root s = 8TeV. The lepton-plus-jets final state is used, where the top pair decays to W (+) bW(-)(b) over bar, 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 Gamma/m = 15% decaying to tt. 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.
ISSN: 1029-8479
Persistent Link: http://dx.doi.org/10.1007/JHEP08(2015)148
http://hdl.handle.net/10735
Bibliographic Citation: Aad, G., B. Abbott, J. Abdallah, O. Abdinov, et al. 2015. "A search for t(t)over-bar resonances using lepton-plus-jets events in proton-proton collisions at root s=8 TeV with the ATLAS detector." Journal of High Energy Physics: 148-148.
Terms of Use:
©2015
Sponsors:

Files in this item

Files Size Format View
NSM-2307-273694.69.pdf 1.652Mb PDF View/Open Article

This item appears in the following Collection(s)


Show full item record