Search for anomalous $\boldmath{Wtb}$ couplings in single top quark production

Abstract

In 0.9 fb${}^{-1}$ of $p\bar{p}$ collisions, D0 has observed an excess of events with an isolated lepton, missing transve rse momentum, and two to four jets. This excess is consistent with single top quark production. We examine these data to study the Lorentz structure of the $Wtb$ coupling. The standard model predicts a left-handed vector coupling at the $Wtb$ vertex. The most general lowest dimension, CP-conserving Lagrangian admits right-handed vector and left- or right-h anded tensor couplings as well. We find that the data prefer the left-handed vector coupling and set upper limits on the anomalous couplings. These are the first direct constraints on a general $Wtb$ interaction and the first direct limits on left- and right-handed tensor couplings.

7 pages, 4 figures

References in corpus (4)

• Evidence for production of single top quarks and first direct measurement of |Vtb|
• Search for W-prime boson resonances decaying to a top quark and a bottom quark
• Search for production of single top quarks via flavor-changing neutral currents at the Tevatron
• Model-independent measurement of the W boson helicity in top quark decays

Cited by in corpus (5)

• The Top Quark Decay Vertex in Standard Model Extensions
• Search for anomalous top quark couplings with the D0 detector
• Review of Properties of the Top Quark from Measurements at the Tevatron
• tbW vertex in the Littlest Higgs Model with T-parity
• Single Top Quarks at the Tevatron