Orateur
Shabnam Jabeen
(Brown University)
Description
We present studies of single top production using the D0 experiment. Single top events are selected with an isolated electron or muon missing transverse energy, two, three or four jets, with one or of them identified as originating from the fragmentation of $b$ quarks. From the cross section measurement we obtain new bounds on the Kobayashi-Maskawa $|V_{tb}|$ matrix element. A model-independent measurement of $t$-channel electroweak production of single top gives a cross section $\sigma(p\bar{p}\to tbq+X)=2.90\pm0.59{\text(stat+syst)}$ pb for a top quark mass of 172.5 GeV. We estimate the probability of the background to fluctuate and produce a signal as large as the one observed to be $1.6\times10^{-8}$, corresponding to a significance of 5.5 standard deviations. We also present search for anomalous top quark production and for CP violation in single top production. The total width of the top quark, $\Gamma_t$, is measured from the partial decay width $\Gamma(t\to Wb)$ measured using the $t$-channel cross section for single top quark production and from the branching fraction $\mathcal{B}(t\to Wb)$ measured in $t\bar{t}$ events
Auteur principal
Dr
Marco VERZOCCHI
(Fermilab)
