Skip to main content
eScholarship
Open Access Publications from the University of California

Evidence for the associated production of a W boson and a top quark in ATLAS at √s=7TeV

  • Author(s): Aad, G
  • Abbott, B
  • Abdallah, J
  • Abdel Khalek, S
  • Abdelalim, AA
  • Abdinov, O
  • Abi, B
  • Abolins, M
  • AbouZeid, OS
  • Abramowicz, H
  • Abreu, H
  • Acerbi, E
  • Acharya, BS
  • Adamczyk, L
  • Adams, DL
  • Addy, TN
  • Adelman, J
  • Adomeit, S
  • Adragna, P
  • Adye, T
  • Aefsky, S
  • Aguilar-Saavedra, JA
  • Aharrouche, M
  • Ahlen, SP
  • Ahles, F
  • Ahmad, A
  • Ahsan, M
  • Aielli, G
  • Akdogan, T
  • Åkesson, TPA
  • Akimoto, G
  • Akimov, AV
  • Akiyama, A
  • Alam, MS
  • Alam, MA
  • Albert, J
  • Albrand, S
  • Aleksa, M
  • Aleksandrov, IN
  • Alessandria, F
  • Alexa, C
  • Alexander, G
  • Alexandre, G
  • Alexopoulos, T
  • Alhroob, M
  • Aliev, M
  • Alimonti, G
  • Alison, J
  • Allbrooke, BMM
  • Allport, PP
  • Allwood-Spiers, SE
  • Almond, J
  • Aloisio, A
  • Alon, R
  • Alonso, A
  • Alvarez Gonzalez, B
  • Alviggi, MG
  • Amako, K
  • Amelung, C
  • Ammosov, VV
  • Amorim, A
  • Amram, N
  • Anastopoulos, C
  • Ancu, LS
  • Andari, N
  • Andeen, T
  • Anders, CF
  • Anders, G
  • Anderson, KJ
  • Andreazza, A
  • Andrei, V
  • Anduaga, XS
  • Angerami, A
  • Anghinolfi, F
  • Anisenkov, A
  • Anjos, N
  • Annovi, A
  • Antonaki, A
  • Antonelli, M
  • Antonov, A
  • Antos, J
  • Anulli, F
  • Aoun, S
  • Aperio Bella, L
  • Apolle, R
  • Arabidze, G
  • Aracena, I
  • Arai, Y
  • Arce, ATH
  • Arfaoui, S
  • et al.
Abstract

© 2012 CERN This Letter presents evidence for the associated production of a W boson and a top quark using 2.05 fb−1of pp collision data at s=7TeV 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 3.3σ level, the expected sensitivity assuming the Standard Model production rate being 3.4σ. The corresponding cross-section is determined and found to be σWt=16.8±2.9 (stat)±4.9 (syst) pb, in good agreement with the Standard Model expectation. From this result the CKM matrix element |Vtb|=1.03−0.19+0.16is derived assuming that the Wt production through |Vts| and |Vtd| is small.

Many UC-authored scholarly publications are freely available on this site because of the UC Academic Senate's Open Access Policy. Let us know how this access is important for you.

Main Content
Current View