2020 Impact factor 4.590
Particles and Fields

Eur. Phys. J. C 16, 269-278
DOI 10.1007/s100520000424

Probe of the Wtb coupling in $t \bar{t}$ pair production
at linear colliders

E. Boos1,2 - M. Dubinin1,2 - M. Sachwitz2 - H.J. Schreiber2

1 Institute of Nuclear Physics, Moscow State University, 119899, Moscow, Russia
2 DESY-Zeuthen, 15738 Zeuthen, Germany

Received: 20 January 2000 / Revised version: 12 April 2000 /
Published online: 18 May 2000 - © Springer-Verlag 2000

The Wtb vertex can be probed on future colliders in the processes of single top production (LHC, pp mode, NLC, $\gamma e$ mode) and of top pair production (NLC, e+ e- mode). We analyze observables sensitive to anomalous Wtb couplings in the top pair production process of e+ e- collisions. In particular, forward-backward and spin-spin asymmetries of the top decay products and the asymmetry of the lepton energy spectrum are considered. Possible bounds on anomalous couplings obtained are competitive to those expected from the upgraded Tevatron and LHC. The validity of the infinitely small width approximation for the three-body top decay is also studied in detail.

Copyright Società Italiana di Fisica, Springer-Verlag 2000