22-29 July 2015
Europe/Vienna timezone

Measurement of the properties of top quarks in decays (includes W polarization, top quark charge and couplings)

Jul 25, 2015, 10:13 AM


talk Top and Electroweak Physics Top and Electroweak Physics


Jonatan Piedra Gomez (Universidad de Cantabria (ES))


Several measurements of top quark properties in top quark decays are presented using data collected by the CMS experiment during the years 2011 and 2012. The polarization of W bosons in top quark decays is measured. The W-boson helicity fractions and angular asymmetries are extracted and limits on anomalous contributions to the Wtb vertex are determined. Furthermore, searches for flavor-changing neutral currents in top quark decays are presented using samples of top-quark pair event candidates decaying via Wb and Zq into lνb and llq events. The flavor contents in top-quark pair events are measured using the fraction of top quarks decaying into a W-boson and a b-quark relative to all top quark decays, R=BR(t->Wb)/Sum(BR(t->Wq)), and the result is used to determine the CKM matrix element Vtb as well as the width of the top quark resonance. The top-quark charge is measured, using the charge correlations between high-pT muons from W boson decays and soft muons from B-hadron decays in b jets.

Primary author

Arnd Meyer (Rheinisch-Westfaelische Tech. Hoch. (DE))

Presentation materials