TY - JOUR
T1 - 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
AU - The CMS collaboration
AU - Khachatryan, V.
AU - Sirunyan, A. M.
AU - Tumasyan, A.
AU - Adam, W.
AU - Asilar, E.
AU - Bergauer, T.
AU - Brandstetter, J.
AU - Brondolin, E.
AU - Dragicevic, M.
AU - Erö, J.
AU - Flechl, M.
AU - Friedl, M.
AU - Frühwirth, R.
AU - Ghete, V. M.
AU - Hartl, C.
AU - Hörmann, N.
AU - Hrubec, J.
AU - Jeitler, M.
AU - König, A.
AU - Krätschmer, I.
AU - Liko, D.
AU - Matsushita, T.
AU - Mikulec, I.
AU - Rabady, D.
AU - Rad, N.
AU - Rahbaran, B.
AU - Rohringer, H.
AU - Schieck, J.
AU - Strauss, J.
AU - Treberer-Treberspurg, W.
AU - Waltenberger, W.
AU - Wulz, C. E.
AU - Mossolov, V.
AU - Shumeiko, N.
AU - Suarez Gonzalez, J.
AU - Alderweireldt, S.
AU - De Wolf, E. A.
AU - Janssen, X.
AU - Lauwers, J.
AU - Van De Klundert, M.
AU - Van Haevermaet, H.
AU - Van Mechelen, P.
AU - Van Remortel, N.
AU - Van Spilbeeck, A.
AU - Abu Zeid, S.
AU - Blekman, F.
AU - D’Hondt, J.
AU - Marlow, Daniel Robert
AU - Olsen, James D.
AU - Tully, Christopher George
N1 - Publisher Copyright:
© 2017, The Author(s).
PY - 2017/2/1
Y1 - 2017/2/1
N2 - 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 |fV R| < 0.16, |fT L| < 0.057, and − 0.049 < fT R < 0.048, respectively. For the FCNC couplings κtug and κtcg, the 95% CL upper limits on coupling strengths are |κtug|/Λ < 4.1 × 10− 3 TeV−1 and |κtcg|/Λ < 1.8 × 10− 2 TeV−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.[Figure not available: see fulltext.]
AB - 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 |fV R| < 0.16, |fT L| < 0.057, and − 0.049 < fT R < 0.048, respectively. For the FCNC couplings κtug and κtcg, the 95% CL upper limits on coupling strengths are |κtug|/Λ < 4.1 × 10− 3 TeV−1 and |κtcg|/Λ < 1.8 × 10− 2 TeV−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.[Figure not available: see fulltext.]
KW - Flavour Changing Neutral Currents
KW - Hadron-Hadron scattering (experiments)
KW - Top physics
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U2 - 10.1007/JHEP02(2017)028
DO - 10.1007/JHEP02(2017)028
M3 - Article
AN - SCOPUS:85012230357
SN - 1126-6708
VL - 2017
JO - Journal of High Energy Physics
JF - Journal of High Energy Physics
IS - 2
M1 - 28
ER -