English

The t->WZb decay in the Standard Model: A Critical Reanalysis

High Energy Physics - Phenomenology 2009-10-31 v2

Abstract

We compute the t->WZb decay rate, in the Standard Model, at the leading order in perturbation theory, with special attention to the effects of the finite widths of the W and Z bosons. These effects are extremely important, since the t->WZb decay occurs near its kinematical threshold. They increase the value of the decay rate by orders of magnitude near threshold or allow it below the nominal threshold. We discuss a procedure to take into account the finite-width effects and compare the results with previous studies of this decay. Within the Standard Model, for a top quark mass in the range between 170 and 180 GeV, we find BR(t->WZb) ~ 2 x 10^{-6}, which makes the observation at the LHC very difficult if at all possible.

Keywords

Cite

@article{arxiv.hep-ph/0010090,
  title  = {The t->WZb decay in the Standard Model: A Critical Reanalysis},
  author = {G. Altarelli and L. Conti and V. Lubicz},
  journal= {arXiv preprint arXiv:hep-ph/0010090},
  year   = {2009}
}

Comments

10 pages, 4 eps figures, LaTeX. Few references added and minor changes in the text. Results unchanged. Final version to appear on PLB