Anomalous triple gauge couplings from BB-meson and kaon observables

We consider the three CP-conserving dimension-6 operators that encode the leading new-physics effects in the triple gauge couplings. The contributions to the standard-model electromagnetic dipole and semi-leptonic vector and axial-vector interactions that arise from the insertions of these operators are calculated. We show that radiative and rare $B$-meson decays provide, under certain assumptions, constraints on two out of the three anomalous couplings that are competitive with the restrictions obtained from LEP II, Tevatron and LHC data. The constraints arising from the $Z \to b \bar b$ electroweak pseudo observables, $K \to \pi \nu \bar \nu$ and $\epsilon^\prime/\epsilon$ are also studied.Comment: 17 pages, 4 figures, v2: journal version, extended comments and added reference

QCD corrections to the Wilson coefficients C9 and C10 in two-Higgs doublet models

In this letter we present the analytic results for the two-loop corrections to the Wilson coefficients C_9(mu_W) and C_10(mu_W) in type-I and type-II two-Higgs-doublet models at the matching scale mu_W. These corrections are important ingredients for next-to-next-to-leading logarithmic predictions of various observables related to the decays B -> X_s l^+ l^- in these models. In scenarios with moderate values of tan(beta) neutral Higgs boson contributions can be safely neglected for e,mu. Therefore we concentrate on the contributions mediated by charged Higgs bosons.Comment: 12 pages, 3 figure

Electroweak Corrections to Bs,d→ℓ+ℓ−B_{s,d} \to \ell^+ \ell^-

We calculate the full two-loop electroweak matching corrections to the operator governing the decay B_q --> l^+ l^- in the Standard Model. Their inclusion removes an electroweak scheme and scale uncertainty of about 7% of the branching ratio. Using different renormalization schemes of the involved electroweak parameters, we estimate residual perturbative electroweak and QED uncertainties to be less than 1% at the level of the branching ratio.Comment: 16 pages, 6 figures, supplementary Mathematica file "c10.m" with analytical results; v2: references update

Theoretical Status of Rare B Decays with Muons

Rare B decays allow to investigate fundamental interactions regarding their flavor, chiral, Dirac and CP properties. In anticipation of the large data samples of exclusive B decays into muons from the forthcoming LHC experiments, in particular LHCb, as well as possible super flavor factories, we review the theoretical status and outline future opportunities to explore the borders of the Standard Model and beyond.Comment: 7 pages, 3 figures; to appear in the proceedings of BEAUTY 2009, the 12th International Conference on B-Physics at Hadron Machines, September 7-11, 2009, Heidelberg; contains previously unpublished plots with New Physics scans over C_7,9,10^(') from the same production line of arXiv:0805.2525 [hep-ph