LHC semileptonic and radiative rare B decays program

P Koppenburg

doi:10.1016/j.nuclphysbps.2006.12.072

Abstract

Rare loop-induced decays are sensitive to New Physics in many Standard Model extensions. In this paper we discuss the reconstruction of the radiative penguin decays b → s γ and the electroweak penguin decay b → l l s at the LHC. The expected annual yields and B/S estimates are presented.

Highlights

Rare loop-induced decays are sensitive to New Physics in many Standard Model extensions
The complex couplings of new particles may result in enhancement of decay rates or in the appearance of non-trivial CP-violating phases
For example for the decay Bd→K∗γ because of the one-diagram dominance the direct CPasymmetry is reliably predicted in the SM to be ≤ 1% [2], but for some SUSY scenarios it could be as large as 10–40% [2,3]

Summary

Radiative B meson decays at LHCb

Radiative b→sγ decays can be reconstructed in the modes Bd→K∗γ1 and Bs→φγ [12]. K∗. The Λb is expected to be polarised in pp collisions at LHC, especially in the forward region This polarisation is assumed to be 20%, a fraction that will be measured to a 1% precision with Λb → J/ψΛ decays [16]. With these yields LHCb will be able to measure the right-handed polarisation component to an accuracy of 5% after 5 years of data taking (10 fb−1), which is smaller than the expected SM contribution [17]. This accuracy only depends weakly on the actual value of the Λb polarisation

AFB at the LHC

RK at LHCb

Findings

Conclusion