Single Top Production and Extra Dimensions

In extra dimension theories, where the gauge bosons of the standard model propagate in the bulk of the extra dimensions, there are Kaluza-Klein excitations of the standard model gauge bosons that can couple to the standard model fermions. In this paper we study the effects of the excited Kaluza-Klein modes of the $W$ on single top production at the Tevatron.Comment: 8 pages, one fig. Talk presented at MRST 2002, Perimeter Institute, Waterloo, Ontari

BsB_s Mixing and New Physics in hadronic b→sqˉqb \to s \bar{q} q transitions

We study the implication of the recent $\Delta m_s$ measurement on $b \to s \bar{q} q$ transitions. We show that it is possible, in the presence of a flavour symmetry, that the phase in $B_s$ mixing may be unobservable even with new CP odd phases in $b \to s$ transitions. These phases may then produce new CP odd effects in certain $b \to s \bar{q} q$ transitions like $B \to K \pi$ but not in others like $B_d \to \phi K_s$. Working in a two higgs doublet model of new physics we discuss the allowed NP contribution to $B \to K \pi$ and $B_d \to \phi K_s$ decays with the new $Delta m_s$ measurement.Comment: 19 pages, no figures, references added, text added, accepted for publicatio

The Full B→D∗τ−ντˉB \to D^{*} \tau^{-} \bar{\nu_\tau} Angular Distribution and CP violating Triple Products

We perform a comprehensive study of the impact of new-physics operators with different Lorentz structures on \BDstarellnu decays, $(\ell = e, \mu, \tau$) involving the $b \to c l \nu_\ell$ transition. We present the full three angle and $q^2$ angular distribution with new physics operators with complex couplings. Various observables are constructed from the angular distribution with special focus on the CP violating triple product asymmetries which vanish in the Standard Model without any hadronic complications. Two of the three triple products are only sensitive to vector/axial vector new physics operators. %and do not depend on pseudoscalar new physics. Hence, the measurements of non-zero triple-product asymmetries will be a clear sign of new physics and a strong signal for vector/axial vector new physics operators. Even though we focus on $\tau$ final state, one can use the triple-products to search for new physics with $e$ and $\mu$ in the final state.Comment: 31 pages, 35 figures, references added, discussion added. arXiv admin note: text overlap with arXiv:1206.3760. Journal of High Energy Physics, Volume 2013, Issue