Search for Anomalous Wtb Couplings and Flavour-Changing Neutral Currents in t-Channel Single Top Quark Production in Pp Collisions at √s = 7 and 8 TeV
In: Springer, 2018
Online
academicJournal
Zugriff:
Single top quark events produced in the t channel are used to set limits on anomalous Wtb couplings and to search for top quark flavour-changing neutral current (FCNC) interactions. The data taken with the CMS detector at the LHC in proton-proton collisions at √s = 7 and 8 TeV correspond to integrated luminosities of 5.0 and 19.7 fb⁻¹, respectively. The analysis is performed using events with one muon and two or three jets. A Bayesian neural network technique is used to discriminate between the signal and backgrounds, which are observed to be consistent with the standard model prediction. The 95% confidence level (CL) exclusion limits on anomalous right-handed vector, and left- and right-handed tensor Wtb couplings are measured to be |fVR| < 0.16, |fTL| < 0.057, and − 0.049 < fTR< 0.048, respectively. For the FCNC couplings κtugand κtcg, the 95% CL upper limits on coupling strengths are |κtug|/Λ < 4.1 × 10⁻³TeV⁻¹and |κtcg|/Λ < 1.8 × 10⁻²TeV⁻¹, where Λ is the scale for new physics, and correspond to upper limits on the branching fractions of 2.0 × 10⁻⁵ and 4.1 × 10⁻⁴ for the decays t → ug and t → cg, respectively. Keywords: Flavour Changing Neutral Currents; Hadron-Hadron scattering (experiments); Top physics
Titel: |
Search for Anomalous Wtb Couplings and Flavour-Changing Neutral Currents in t-Channel Single Top Quark Production in Pp Collisions at √s = 7 and 8 TeV
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Autor/in / Beteiligte Person: | Collaboration, CMS ; Abercrombie, Daniel Robert ; Allen, Brandon Leigh ; Apyan, Aram ; Barbieri, Richard Alexander ; Baty, Austin Alan ; Bi, Ran ; Bierwagen, Katharina ; Brandt, Stephanie Akemi ; Busza, Wit ; Cali, Ivan Amos ; Demiragli, Zeynep ; Di Matteo, Leonardo ; Gomez-Ceballos, Guillelmo ; Goncharov, Maxim ; Hsu, Dylan George ; Iiyama, Yutaro ; Innocenti, Gian Michele ; Klute, Markus ; Kovalskyi, Dmytro ; Krajczar, Krisztian F. ; Lai, Yue Shi ; Lee, Yen-Jie ; Levin, Amy Elizabeth ; Luckey Jr, P David ; Marini, Andrea Carlo ; McGinn, Christopher Francis ; Mironov, Camelia Maria ; Narayanan, Siddharth Madhavan ; Niu, Xinmei ; Paus, Christoph M. E. ; Roland, Christof E ; Roland, Gunther M ; Salfeld-Nebgen, Jakob Maxillian Henry ; Stephans, George S. F. ; Sumorok, Konstanty C ; Tatar, Kaya ; Varma, Mukund Madhav ; Velicanu, Dragos Alexandru ; Veverka, Jan ; Wang, Jing ; Wang, Ta-Wei ; Wyslouch, Boleslaw ; Yang, Ming ; Wyslouch, Victoria ; Massachusetts Institute of Technology. Department of Nuclear Science and Engineering ; Massachusetts Institute of Technology. Department of Physics ; Massachusetts Institute of Technology. Laboratory for Nuclear Science |
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Zeitschrift: | Springer, 2018 |
Veröffentlichung: | Springer Nature, 2018 |
Medientyp: | academicJournal |
ISSN: | 1029-8479 (print) |
DOI: | 10.1007/JHEP02(2017)028 |
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