Evidence for the associated production of a W boson and a top quark in ATLAS at root s=7 TeV
- NázevTitle
- Evidence for the associated production of a W boson and a top quark in ATLAS at root s=7 TeVEvidence for the associated production of a W boson and a top quark in ATLAS at root s=7 TeV
- Druh výsledkuResult type
- Článek v časopiseJournal article
- AutořiAuthors
- G. Aad, B. Abbott, J. Abdallah, S. Abdel Khalek, A. A. Abdelalim, K. Augsten, T. Holý, Z. Hubáček, J. Jakůbek, Z. Kohout, V. Král, F. Krejčí, S. Pospíšil, V. Šimák, T. Slavíček, K. Smolek, J. Sodomka, M. Solar, J. Šolc, B. Sopko, V. Sopko, I. Štekl, D. Tureček, V. Vacek, M. Vlasák, P. Vokáč
- DOIDOI
- 10.1016/j.physletb.2012.08.011
- Časopis / citaceJournal / citation
- Physics Letters B. 2012, 716(1), 142-159. ISSN 0370-2693.
- RokYear
- 2012
- JazykLanguage
- eng
- WoSWoS
- 000309621400007
- ScopusScopus
- 2-s2.0-85042037870
- RIVRIV
- RIV/68407700:21220/12:00202648!RIV13-MSM-21220___
- ProjektProject
- Matematické, počítačové a experimentální metody ve fyziceMathematical, Computer and Experimental Methods in Physics; Mezinárodní experiment ATLAS-CERNInternational Experiment ATLAS-CERN; Centrum částicové fyzikyCenter for Particle Physics; Fundamentální experimenty ve fyzice mikrosvětaFundamental Experiments in Physics of Microworld; Matematické, počítačové a experimentální metody ve fyziceMathematical, Computer and Experimental Methods in Physics; Mezinárodní experiment ATLAS-CERNInternational Experiment ATLAS-CERN
AbstraktAbstract
This Letter presents evidence for the associated production of a W boson and a top quark using 2.05 fb(-1) of pp collision data at root s = 7 TeV accumulated with the ATLAS detector at the LHC. The analysis is based on the selection of the dileptonic final states with events featuring two isolated leptons, electron or muon, with significant transverse missing momentum and at least one jet. An approach based on boosted decision trees has been developed to improve the discrimination of single top-quark Wt events from background. A template fit to the final classifier distributions is performed to determine the cross-section. The result is incompatible with the background-only hypothesis at the 3.3 sigma level, the expected sensitivity assuming the Standard Model production rate being 3.4 sigma. The corresponding cross-section is determined and found to be sigma(wt) = 16.8 +/- 2.9 (stat) +/- 4.9 (syst) pb, in good agreement with the Standard Model expectation. From this result the CKM matrix element vertical bar V-tb vertical bar = 1.03(-0.19)(+0.16) is derived assuming that the Wt production through vertical bar V-ts vertical bar and vertical bar V-td vertical bar is small.
This Letter presents evidence for the associated production of a W boson and a top quark using 2.05 fb(-1) of pp collision data at root s = 7 TeV accumulated with the ATLAS detector at the LHC. The analysis is based on the selection of the dileptonic final states with events featuring two isolated leptons, electron or muon, with significant transverse missing momentum and at least one jet. An approach based on boosted decision trees has been developed to improve the discrimination of single top-quark Wt events from background. A template fit to the final classifier distributions is performed to determine the cross-section. The result is incompatible with the background-only hypothesis at the 3.3 sigma level, the expected sensitivity assuming the Standard Model production rate being 3.4 sigma. The corresponding cross-section is determined and found to be sigma(wt) = 16.8 +/- 2.9 (stat) +/- 4.9 (syst) pb, in good agreement with the Standard Model expectation. From this result the CKM matrix element vertical bar V-tb vertical bar = 1.03(-0.19)(+0.16) is derived assuming that the Wt production through vertical bar V-ts vertical bar and vertical bar V-td vertical bar is small.