Search for single top quark production in pp¯ collisions at s=1.96 TeV in the missing transverse energy plus jets topology

Le résumé fourni par la source

We report a search for single top quark production with the CDF II detector using $2.1\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ of integrated luminosity of $p\overline{p}$ collisions at $\sqrt{s}=1.96\text{ }\text{ }\mathrm{TeV}$. The data selected consist of events characterized by large energy imbalance in the transverse plane and hadronic jets, and no identified electrons and muons, so the sample is enriched in $W\ensuremath{\rightarrow}\ensuremath{\tau}\ensuremath{\nu}$ decays. In order to suppress backgrounds, additional kinematic and topological requirements are imposed through a neural network, and at least one of the jets must be identified as a $b$ quark jet. We measure an excess of signal-like events in agreement with the standard model prediction, but inconsistent with a model without single top quark production by 2.1 standard deviations ($\ensuremath{\sigma}$), with a median expected sensitivity of $1.4\ensuremath{\sigma}$. Assuming a top quark mass of $175\text{ }\text{ }\mathrm{GeV}/{c}^{2}$ and ascribing the excess to single top quark production, the cross section is measured to be ${4.9}_{\ensuremath{-}2.2}^{+2.5}(\mathrm{stat}+\mathrm{syst})\text{ }\text{ }\mathrm{pb}$, consistent with measurements performed in independent data sets and with the standard model prediction.

Ce résumé expose les affirmations des auteurs. BNTIC ne l’interprète pas comme une validation indépendante des résultats.