Top-quark Polarisation at colliders

par Rohini Godbole (Bangalore)

mardi 23 nov. 2010, 14:00 → 15:00 Europe/Paris

Auditorium M. Vivargent (LAPTH)

In this talk I will discuss top-quark polarisation as a probe to study the SM and BSM physics at the colliders. I will show how single top polarisation can provide possibilities of discrimination among different BSM explanations that have been suggested to explain the forward backward asymmetry at the Tevatron. I will talk about different probes of top polarisation that can be constructed using decay lepton energy and angle distributions, pointing out a special feature of angular distributions which make them a particularly robust probe of polarisation. Further, I will point out a method of constructing observables which can probe polarisation asymmetries, which works also at the LHC which does not have a preferred direction. I will illustrate this with an example of a $t\bar t$ resonance production at the LHC, where one expects nonzero top polarization. If time is left I will also discuss the effect of anomalous $tbW$ interactions on the use of probes constructed using decay product energies, which may be the only option for heavily boosted top quarks, expected, for example, in the warped extra dimensional models.

Slides Godbole