Related papers: B_{s,d} -> l+ l- in a Two-Higgs-Doublet Model
We confront the Two-Higgs-Doublet Model with a variety of experimental constraints as well as theoretical consistency conditions. The most constraining data are the \bar B\to X_s\gamma decay rate (at low values of M_{H^\pm}), and \Delta\rho…
During the last few years the Tevatron has dramatically improved the bounds on rare B-meson decays into two leptons. In the case of B_s --> mu+ mu-, the current bound is only ten times greater than the Standard Model expectation.…
The charged Higgs boson plays an essential role in distinguishing between a wide variety of standard model extensions with multiple Higgs doublets, and has been searched for in various collider experiments. This paper expands our previous…
We investigate the phenomenology of the charged Higgs boson within the Two-Higgs-Doublet Type-II Seesaw Model (2HDMcT Type-III) at future $\mu^+ \mu^-$ colliders. Focusing on $2 \to 2$ processes such as $\mu^+ \mu^- \to H^+_1 S^-$ ($S^- =…
The branching fraction of the rare $B^0_s\rightarrow\phi\mu^+\mu^-$ decay is measured using data collected by the LHCb experiment at center-of-mass energies of $7$, $8$ and $13\,\rm{TeV}$, corresponding to integrated luminosities of $1$,…
We calculate the ratio of the two branching ratios, Br(h -> bb-bar) and Br(h -> cc-bar) + Br(h -> gg), in the minimal supersymmetric standard model taking into account the SUSY-loop corrections to the Higgs sector and the hbb-bar vertex. We…
We show that in the Two Higgs Doublet Model (THDM) Type I the partial decay width of h --> gamma gamma can be considerably larger than in Type II, due to light charged scalars with a mass about 100 GeV, which are not yet excluded in Type I.…
As a result of the helicity suppression effect, within the Standard Model the rare decay channel $B_s \to e^+ e^-$ has a decay probability which is five orders of magnitude below current experimental limits. Thus, any observation of this…
In this work, we study the radiative leptonic decays of $B^-$ and $D^-$ mesons in the standard model and the two-Higgs-doublet-model type II. The results are obtained using the factorization procedure, and the contribution of the order…
Charged Higgs decays are discussed within an effective lagrangian extension of the two-higgs doublet model, assuming new physics appearing in the Higgs sector of this model. Low energy constrains are used to imposse bounds on certain…
We study the Two Higgs Doublet Model of type II, set limits to the parameter $\tan\beta$ as a function of the mass of the charged Higgs $m_{H}$, and find interesting discovery channels in hadron colliders or muon colliders. We also obtain…
Charged Higgs bosons are common predictions in most extensions of the Standard Model (SM) Higgs sector. Therefore, their observation would elucidate the nature of the Higgs sector. Motivated by the ATLAS collaboration's latest analysis…
We study the dominant decays of the lightest Higgs boson in models with 2 and 3 Higgs doublets, for the case when its couplings to fermions are absent at tree-level. It is found that the branching ratio for the decay $H\to \gamma\gamma$ is…
We calculate in the framework of two Higgs doublet models the differential decay rate for inclusive $\bar B\to\tau\,\bar\nu\,X$ transitions to order $1/m_b^2$ in the heavy quark expansion, for both polarized and unpolarized tau leptons. In…
We present the results of a search for $B^{+}\to\gamma \ell^{+}\nu_{\ell}$, where $\ell = e, \mu$. We use a sample of 232 million $B\bar{B}$ pairs recorded at the $\Upsilon(4S)$ with the BaBar detector at the PEP-II $B$ Factory. We measure…
The search for additional Higgs particles and the exact measurements of Higgs (self-) couplings is a major goal of future collider experiments. In this paper we investigate the possible sizes of new physics signals in these searches in the…
We discuss the constraints on the supersymmetric parameter space from the decay mode b -> s \gamma for large values of tan\beta. We improve the theoretical prediction for the decay rate by summing very large radiative corrections to all…
The phenomenology of the low scale U(1)_{B-L} extension of the standard model and its implications at LHC is presented. In this model, an extra gauge boson corresponding to B-L gauge symmetry and an extra SM singlet scalar (heavy Higgs) are…
We comprehensively study the charged-Higgs contributions to the leptonic $B^-_q \to \ell \bar \nu$ ($q=u,c$) and semileptonic $\bar B \to X_q \ell \bar\nu$ ($X_u=\pi, \rho; X_c=D,D^*$) decays in the type-III two-Higgs-doublet model (2HDM).…
An angular analysis and a measurement of the differential branching fraction of the decay $B^0_s\to\phi\mu^+\mu^-$ are presented, using data corresponding to an integrated luminosity of $3.0\, {\rm fb^{-1}}$ of $pp$ collisions recorded by…