Exclusive B → V γ decays in the T2HDM

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By employing the QCD factorization approach for the exclusive B → V γ decays, we calculated the new physics contributions to the branching ratios, CP asymmetries, isospin and U-spin symmetry breaking of B → K*γ and B → ργ decays, induced by the charged Higgs penguin diagrams appeared in the top-quark two-Higgs-doublet model(T2HDM). Within the considered parameter space, we found that (a) a charged-Higgs boson with a mass larger than 300 GeV are always allowed by the date of B → V γ decay, and such lower limit on are comparable with those obtained from the inclusive B → Xₛ γ decay; (b) the CP asymmetry of B → ργ in the T2HDM can be as large as 10% in magnitude and has a strong dependence on the angle θ and the CKM angle γ; (c) the isospin symmetry breakings of B → V γ decays in the T2HDM are generally small in size: around 6% for B → K* γ decay and less than 20% for B → ργ decay; and (d) the U-spin symmetry breaking ΔU(K*,ρ) in the T2HDM is also small in size, only about 8% of the branching ratio (B → ρ⁰ γ).