DIRECT CP ASYMMETRY IN INCLUSIVE RARE B-DECAYS IN 2HDM

Abstract

The direct CP asymmetry in the inclusive B → Xdγ and B → Xde+e-decays is investigated in the two-Higgs doublet extension of the Standard Model (2HDM). The investigation is performed in the lowest nonvanishing order of the perturbation theory using the existing restrictions on the 2HDM parameters space. It is shown that the direct CP asymmetry in the B → Xdγ decay can deviate significantly from the Standard Model predictions. In the presence of only one source of CP violation (the CKM matrix weak phase) aCP(B → Xdγ) can have the sign opposite to that in the SM. The new source of CP violation can make |aCP(B → Xdγ)| arbitrary small (unlike the SM case) and hence unmeasurable. Quantitatively, the obtained results suffer from the uncertainty of the choice of renormalization scale. As for the B → Xde+e-rate asymmetry, its renormalization scale dependence in the lowest nonvanishing order does not allow to conclude if this quantity is efficient for testing new physics beyond the Standard Model.