相关论文: Charged-Higgs effects in a new B -> D tau nu diffe…
We update and compare the capabilities of the purely leptonic mode B --> tau nu and the semileptonic mode B --> D tau nu in the search for a charged Higgs boson.
B physics is sensitive to the effects of Higgs bosons in the Minimal Supersymmetric Standard Model, if the parameter tan beta is large. I briefly summarise the role of B -> mu+ mu- and B -> tau nu in the hunt for new Higgs effects and…
We study the charged Higgs effects on the decays of $B^{-} \to \tau \bar\nu_{\tau}$ and $\bar B\to P(V) \ell \bar\nu_{\ell}$ with $P=\pi^{+},D^{+}$ and $V=\rho^{+},D^{*+}$. We concentrate on the minimal supersymmetric standard model with…
The decay modes $\bar{B}\to D^{(*)}\tau\bar{\nu}_{\tau}$ are sensitive to charged scalar effects, such as the charged Higgs effects. In this paper we suggest a method to determine their effects by using the ratio of branching fractions and…
We study the longitudinal polarization of the tau lepton in B -> D tau nu decay. After discussing possible sensitivities of tau decay modes to the tau polarization, we examine the effect of charged Higgs boson on the tau polarization in B…
In this talk I consider the current status of $B \rightarrow D^{(*)} \tau \nu$ decays in the context of two-Higgs-doublet models. The BaBar collaboration has reported an excess in semileptonic $b \rightarrow c \tau \nu$ transitions that has…
We explore charged-Higgs cp-violating effects in a specific type III two-Higgs doublet model which is theoretically attractive as it accommodates the large mass of the top quark in a natural fashion. Two new CP-violating phases arise from…
We study possible scalar type interactions in tau^- -->pi^- pi^0 nu_tau decay. One finds that an angular distribution asymmetry, A(s), can be induced from the interference between the scalar part and vector part amplitudes in this decay.…
We study effects of charged Higgs boson exchange in the $B$ semileptonic decays $\bar B \rightarrow D^{(*)}\tau\bar\nu_\tau$. Both branching ratio and $\tau$ polarization are examined. We use the recent experimental data on semileptonic $B$…
Recent experimental results on exclusive semi-tauonic B meson decays, B -> D(*) tau nu, showing sizable deviations from the standard model prediction, suggest a new physics in which the structure of the relevant weak charged interaction may…
Decays of B mesons to states involving tau leptons can be used as a tool to search for the effects of new physics, such as those involving a charged Higgs boson. The experimental status of the decays B -> tau nu and B -> D^(*) tau nu is…
The decays D(s)+- -> mu+- nu and D(s)+- -> tau+- nu have traditionally been used to measure the D(s)+- meson decay constant f_D(s). Recent measurements at CLEO-c and the B factories suggest a branching ratio for both decays somewhat higher…
We show how the transverse tau tau spin correlations can be used to measure the parity of the Higgs boson and hence to distinguish a CP-even H boson from CP-odd A in the future high energy accelerator experiments. We investigate the…
We demonstrate how the transverse tau tau spin correlations can be used to determine whether a decaying Higgs boson is a mixed CP eigenstate, thereby directly probe the presence of CP violation in the neutral Higgs boson sector. We…
In the Standard Model, scalar contributions to leptonic and semileptonic decays are helicity suppressed. The hypothesis of additional physical neutral/charged Higgses can enhance such scalar contributions and give detectable effects…
Based on the full BaBar data sample, we report improved measurements of the ratios R(D(*)) = B(B -> D(*) Tau Nu)/B(B -> D(*) l Nu), where l is either e or mu. These ratios are sensitive to new physics contributions in the form of a charged…
Based on the full BaBar data sample, we report improved measurements of the ratios R(D(*)) = B(B -> D(*) Tau Nu)/B(B -> D(*) l Nu), where l is either e or mu. These ratios are sensitive to new physics contributions in the form of a charged…
We discuss how a charged Higgs propagator would modify the form factor in tau- -> pi- pi0 nu_tau decays.
It has been known that $B \rightarrow D^{(*)} \tau \nu_{\tau}$ are good observables in the search for the charged Higgs. The recent obervation of deviation from standard-model by almost 4$\sigma$ by Babar, Belle and LHCb in $R(D^{(*)})$…
In this talk I review the status of $B\rightarrow D^{(*)} \tau \nu$ decays within the framework of the aligned two-Higgs-doublet model.