@article{10902/13962,
year = {2014},
month = {9},
url = {http://hdl.handle.net/10902/13962},
abstract = {The ratio of the top-quark branching fractions R = ß(t→Wb)/ß(t →Wq), where the denominator includes the sum over all down-type quarks (q =b, s, d), is measured in the t¯t dilepton final state with proton–proton collision data at vs=8TeVfrom an integrated luminosity of 19.7fb-1, collected with the CMS detector. In order to quantify the purity of the signal sample, the cross section is measured by fitting the observed jet multiplicity, thereby constraining the signal and background contributions. By counting the number of b jets per event, an unconstrained value of R =1.014 ± 0.003 (stat.) ± 0.032 (syst.)is measured, in a good agreement with current precision measurements in electroweak and flavour sectors. A lower limit R >0.955at the 95% confidence level is obtained after requiring R =1, and a lower limit on the Cabibbo–Kobayashi–Maskawa matrix element |Vtb| >0.975 is set at 95% confidence level. The result is combined with a previous CMS measurement of the t-channel single-top-quark cross section to determine the top-quark total decay width, Gt=1.36 ± 0.02 (stat.) + 0.14-0.11 (syst.) GeV.},
publisher = {Elsevier},
publisher = {Physics Letters B, Vol. 736, Pp. 33–57, (2014)},
title = {Measurement of the ratio ß(t→Wb)/ß(t →Wq) in pp collisions at vs = 8 TeV},
author = {Khachatryan, Vladimir and Brochero Cifuentes, Javier Andrés and Cabrillo Bartolomé, José Iban and Calderón Tazón, Alicia and Duarte Campderros, Jorge and Fernández García, Marcos and Gómez Gramuglio, Gervasio and González Sánchez, Francisco Javier and Graziano, Alberto and López Virto, María Amparo and Marco de Lucas, Jesús and Marco de Lucas, Rafael José and Martínez Rivero, Celso and Matorras Weinig, Francisco and Muñoz Sánchez, Francisca Javiela and Piedra Gómez, Jonatan and Rodrigo Anoro, Teresa and Rodríguez Marrero, Ana Yaiza and Ruiz Jimeno, Alberto and Scodellaro, Luca and Vila Álvarez, Iván  and Vilar Cortabitarte, Rocío},
}