Measurement of the forward-backward asymmetry in the distribution of leptons in tt¯ events in the lepton+jets channel

Abazov, V. M. and Abbott, B. and Acharya, B. S. and Adams, M. and Adams, T. and Agnew, J. P. and Alexeev, G. D. and Alkhazov, G. and Alton, A. and Askew, A. and Atkins, S. and Augsten, K. and Avila, C. and Badaud, F. and Bagby, L. and Baldin, B. and Bandurin, D. V. and Banerjee, S. and Barberis, E. and Baringer, P. and Bartlett, J. F. and Bassler, U. and Bazterra, V. and Bean, A. and Begalli, M. and Bellantoni, L. and Beri, S. B. and Bernardi, G. and Bernhard, R. and Bertram, I. and Besanifmmode çelse çon, M. and Beuselinck, R. and Bhat, P. C. and Bhatia, S. and Bhatnagar, V. and Blazey, G. and Blessing, S. and Bloom, K. and Boehnlein, A. and Boline, D. and Boos, E. E. and Borissov, G. and Borysova, M. and Brandt, A. and Brandt, O. and Fox, H. and Price, D. and Ratoff, P. N. and Ross, A. and Williams, M. R. J. (2014) Measurement of the forward-backward asymmetry in the distribution of leptons in tt¯ events in the lepton+jets channel. Physical Review D, 90. ISSN 1550-7998

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We present measurements of the forward-backward asymmetry in the angular distribution of leptons from decays of top quarks and antiquarks produced in proton-antiproton collisions. We consider the final state containing a lepton and at least three jets. The entire sample of data collected by the D0 experiment during Run II of the Fermilab Tevatron Collider, corresponding to 9.7  fb−1 of integrated luminosity, is used. The asymmetry measured for reconstructed leptons is AlFB=(2.9±2.1(stat.)+1.5−1.7(syst.))%. When corrected for efficiency and resolution effects within the lepton rapidity coverage of |yl|<1.5, the asymmetry is found to be AlFB=(4.2±2.3(stat.)+1.7−2.0(syst.))%. We examine the dependence of AlFB on the transverse momentum and rapidity of the lepton. Combination with the asymmetry measured in the final states containing two leptons yields AlFB=(4.2±2.0(stat.)±1.4(syst.))%. The results are in agreement with predictions from the next-to-leading-order QCD generator mc@nlo, which predicts an asymmetry of AlFB=2.0% for |yl|<1.5.

Item Type:
Journal Article
Journal or Publication Title:
Physical Review D
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© 2014 American Physical Society
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Deposited On:
29 Oct 2014 15:53
Last Modified:
05 Jul 2020 04:14