Logo image
Measurement of the ratio B(t→Wb)/B(t→Wq) in pp collisions at s=8 TeV
Journal article   Open access   Peer reviewed

Measurement of the ratio B(t→Wb)/B(t→Wq) in pp collisions at s=8 TeV

Vardan Khachatryan, Cécile Caillol, Barbara Clerbaux, Gilles Lentdecker, Laurent Favart, Arnaud Gay, Anastasia Grebenyuk, Alexandre Leonard, Pierre Marage, Abdollah Mohammadi, …
Physics letters. B, Vol.736, pp.33-57
09/01/2014
DOI: 10.1016/j.physletb.2014.06.076
url
https://doi.org/10.1016/j.physletb.2014.06.076View
Published (Version of record) Open Access

Abstract

The ratio of the top-quark branching fractions R=B(t→Wb)/B(t→Wq), where the denominator includes the sum over all down-type quarks (q = b, s, d), is measured in the tt- dilepton final state with proton-proton collision data at s=8 TeV from an integrated luminosity of 19.7 fb-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>0.955 at the 95% confidence level is obtained after requiring R≤1, and a lower limit on the Cabibbo-Kobayashi-Maskawa matrix element
High Energy Physics Experiment Phenomenology Physique des particules élémentaires Top Width

Details

Metrics

Logo image