Search for anomalous Wtb couplings in single top quark production in ppbar collisions at sqrt(s) = 1.96 TeV

TL;DR

This paper sets new constraints on possible anomalous Wtb couplings by analyzing single top quark production data from the Tevatron collider, testing deviations from the Standard Model predictions.

Contribution

It provides the first direct experimental limits on all possible anomalous Wtb couplings using Tevatron data.

Findings

Stringent limits on right-handed vector couplings.

Constraints on left- and right-handed tensor couplings.

Improved bounds compared to previous indirect measurements.

Abstract

We present new direct constraints on a general $Wtb$ interaction using data corresponding to an integrated luminosity of 5.4 fb$^{-1}$ collected by the D0 detector at the Tevatron $p\bar{p}$ collider. The standard model provides a purely left-handed vector coupling at the $Wtb$ vertex, while the most general, lowest dimension Lagrangian allows right-handed vector and left- or right-handed tensor couplings as well. We obtain precise limits on these anomalous couplings by comparing the data to the expectations from different assumptions on the $Wtb$ coupling.