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Phase Effect of A General Two-Higgs-Doublet Model in $b\to sγ$

David Bowser-Chao·Kingman Cheung·Wai-Yee Keung
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Abstract

In a general two-Higgs-doublet model (2HDM), without the {\it ad hoc} discrete symmetries to prevent tree-level flavor-changing-neutral currents, an extra phase angle in the charged-Higgs-fermion coupling is allowed. We show that the charged-Higgs amplitude interferes destructively or constructively with the standard model amplitude depending crucially on this phase angle. The popular model I and II are special cases of our analysis. As a result of this phase angle the severe constraint on the charged-Higgs boson mass imposed by the inclusive rate of $b\to sγ$ from CLEO can be relaxed. We also examine the effects of this phase angle on the neutron electric dipole moment. Furthermore, we also discuss other constraints on the charged-Higgs-fermion couplings coming from measurements of $B^0-\bar{B^0}$ mixing, $ρ_0$, and $R_b$.

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David Bowser-Chao, Kingman Cheung, Wai-Yee Keung. 1998-11-03. Phase Effect of A General Two-Higgs-Doublet Model in $b\to sγ$. https://doi.org/10.1103/physrevd.59.115006

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