Eur. Phys. J. C 70, 1025-1035 (2010)
https://doi.org/10.1140/epjc/s10052-010-1495-z

Extracting γ and penguin topologies through CP violation in B_s⁰ → J/φ K_S

Nikhef, Science Park 105, 1098 XG, Amsterdam, The Netherlands

Robert.Fleischer@nikhef.nl

Received: 4 October 2010
Published online: 18 November 2010

Abstract

The decay has recently been observed by the CDF collaboration and will be of interest for the LHCb experiment. This channel will offer a new tool to extract the angle γ of the unitarity triangle and to control doubly Cabibbo-suppressed penguin corrections to the determination of sin 2β from the well-known mode with the help of the U-spin symmetry of strong interactions. While any competitive determination of γ is interesting, the latter aspect is particularly relevant as LHCb will enter a territory of precision which makes the control of doubly Cabibbo-suppressed Standard-Model corrections mandatory. Using the data from CDF and the e ⁺ e ⁻ B factories as a guideline, we explore the sensitivity for γ and the penguin parameters and point out that the – mixing phase φ _s , which is only about −2° in the Standard Model but may be enhanced through new physics, is a key parameter for these analyses. We find that the mixing-induced CP violation shows an interesting correlation with sin φ _s , which serves as a target region for the first measurement of this observable at LHCb.