Exclusive decays in general two-Higgs-doublet models
Department of Physics, Nanjing Normal University, 210097, Nanjing, Jiangsu, P.R. China
2 CCAST (World Laboratory), P.O.Box 8730, 100080, Beijing, P.R. China
3 Department of Physics, Nanjing Normal University, 210097, Nanjing, Jiangsu, P.R.China
* e-mail: firstname.lastname@example.org
By employing the QCD factorization approach, we calculated the next-to-leading order new physics contributions to the branching ratios, CP asymmetries, isospin and U-spin symmetry breaking of the exclusive decays (), induced by the charged Higgs penguins in general two-Higgs-doublet models. Within the considered parameter space, we found that (a) the new physics corrections to the observables are generally small in model I and model III-A, moderate in model II, but large in model III-B; (b) from the well measured branching ratios and upper limits, a lower bound of M H > 200 GeV in model II was obtained, while the allowed range of M H in model III-B is GeV; these bounds are comparable with those from the inclusive decay; (c) the NLO Wilson coefficient C 7(m b ) in model III-B is positive and disfavored by the measured value of isospin symmetry breaking , but it still cannot be excluded if we take the large errors into account; (d) the CP asymmetry in model III-B has an opposite sign to the one in the standard model (SM), which may be used as a good observable to distinguish the SM from model III-B; (e) the isospin symmetry breaking is less than in the region of preferred by the global fit result, but it can be as large as 20 to in the regions of and . The SM and model III-B predictions for are opposite in sign for small or large values of the CKM angles; (f) the U-spin symmetry breaking in the SM and the general two-Higgs-doublet models is generally small in size: .
© Springer-Verlag, 2004