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Register a new userMixing-induced CP asymmetry in B-> K* gamma decays with perturbative QCD approach
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The mixing-induced CP asymmetries in B-> K* gamma -> K_S pi^0 gamma and B-> K* gamma -> K_L pi^0 gamma are expected to be small within the standard model. So they are among the most promising decay modes to test the standard model. In this paper, we compute the mixing-induced CP asymmetries in these decay modes, within the framework of the standard model, using perturbative QCD, and our conclusion is S_{K_S pi^0 gamma}=-S_{K_L pi^0 gamma}=-(3.5pm 1.7)times 10^{-2}.
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The radiative B -> K* gamma mode is caused by a penguin operator which is a quantum correction. Thus this mode may be useful in the search for physics beyond the standard model. In this paper, we compute the branching ratio, direct CP asymmetry, and isospin breaking effects within the Standard Model in the framework perturbative QCD, and discuss how new physics might show up in this decay.
The radiative B-> rho gamma, B-> omega gamma decay modes are caused by the FCNC process, so they give us good insight towards probing the standard model in order to search for new physics. In this paper, we compute the branching ratio, direct CP asymmetry, and isospin breaking effects using the perturbative QCD approach within the standard model.
We describe a measurement of the direct CP asymmetry between inclusive b -> s gamma and bbar -> sbar gamma decays. This asymmetry is expected to be less than 0.01 in the Standard Model, but could be enhanced up to about 0.10 by new physics contributions. We use a sample of 89 million BB pairs recorded with the BaBar detector at PEP-II, from which we reconstruct a set of 12 exclusive b -> s gamma final states containing one charged or neutral kaon and one to three pions. We measure an asymmetry of A_CP(b -> s gamma) = 0.025 +/- 0.050(stat.) +/- 0.015(syst.), corresponding to an allowed range of -0.06 < A_CP(b -> s gamma) < +0.11 at 90% confidence level.
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