Time-dependent CP Asymmetry in B->K* gamma as a (Quasi) Null Test of the Standard Model

Abstract

We calculate the dominant Standard Model contributions to the time-dependent CP asymmetry in B0->K*0 gamma, which is O(1/mb) in QCD factorisation. We find that, including all relevant hadronic effects, in particular from soft gluons, the asymmetry S is very small, S=-0.022\pm 0.015^{+0}_{-0.01}, and smaller than suggested recently from dimensional arguments in a 1/mb expansion. Our result implies that any significant deviation of the asymmetry from zero, and in particular a confirmation of the current experimental central value, S_{HFAG}=-0.28\pm 0.26, would constitute a clean signal for new physics.

14 pages, 1 figure, discussions on further power corrections added

References in corpus (6)

• Probing New Physics through B Mixing: Status, Benchmarks and Prospects
• Testing QCD Sum Rules on the Light-Cone in D->(pi,K) l nu Decays
• Photon helicity in Lambda_b --> p K gamma decays
• Null tests of the Standard Model at an International Super $B$ Factory
• Impact of Right-handed Strange-beauty Squark on b <-> s Transitions
• Determining the strange quark mass for 2-flavour QCD

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