Related papers: \tau lepton decays and CVC
We use experimental data on $e^{+}e^{-} \rightarrow \eta\pi^{+}\pi^{-}$ and $\tau^{-} \to \eta\pi^{-}\pi^{0}\nu_{\tau}$ to test conservation of vector current (CVC) by comparing the predicted hadronic spectrum and branching fraction with…
We report on analyses of tau lepton decays $\tau^- \to \eta K^- \nu_{\tau}$ and $\tau^- \to \eta \pi^- \nu_{\tau}$, with $\eta \to \pi^+ \pi^- \pi^0$, using 470 fb$^{-1}$ of data from the Babar experiment at PEP-II, collected at…
We present the first measurements of branching fractions of rare tau-lepton decays, $\tau^- \rightarrow \pi^- \nu_{\tau} \ell^+ \ell^-$ ($\ell = e$ or $\mu$), using a data sample corresponding to 562 fb$^{-1}$ collected at a center-of-mass…
The vector and scalar form factors relevant to the second-class current $\tau^-\to\pi^-\eta^{(\prime)}\nu_\tau$ processes are evaluated supplementing Chiral Perturbation Theory with the inclusion of resonances as explicit degrees of…
Using 4.68 fb^{-1} of e^+e^- annihilation data collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR) we have studied tau radiative decays tau -> mu nu nu gamma and tau -> e nu nu gamma. For a 10 MeV minimum photon…
Based on 3.26 fb$^{-1}$ data sample collected at CLEO III, we study the decay $\tau^-\to K^+K^-\pi^-\nu_\tau$, and improve the measurement of the branching ratio ${\cal B}(\tau^-\to K^+K^-\pi^-\nu_\tau)= (1.59\pm0.06\pm0.13)\times10^{-3}$,…
Using 4.68 fb^{-1} of e^+e^- annihilation data collected with the CLEO II detector we have studied tau radiative decays tau --> mu nu nu gamma and tau --> e nu nu gamma. For a 10 MeV minimum photon energy in the tau rest frame, the…
We have observed new channels for $\tau$ decays with an $\eta$ in the final state. We study 3-prong tau decays, using the $\eta\to\gamma\gamma$ and $\eta\to 3\piz$ decay modes and 1-prong decays with two $\piz$'s using the…
We present a study of tau^- -> K^- pi^+ pi^- nu_tau decay using ~669 /fb data, collected with the Belle detector at the KEKB asymmetric-energy e^+ e- collider. The data is recorded at a center-of-mass energy 10.58 GeV. The result for the…
The \tau \to \omega,\phi \pi^- \nu_\tau decays of the \tau lepton are studied using the method of phenomenological SU(3) * SU(3) chiral Lagrangians. It is shown that the obtained value for the \tau \to \phi \pi \nu_\tau decay probability is…
We study the $\tau^- \to \nu_{\tau} \pi^{-}\pi^{0}\ell^{+}\ell^{-}$ ($\ell=e,\,\mu$) decays, which are $O(\alpha^2)$-suppressed with respect to the dominant di-pion tau decay channel. Both the inner-bremsstrahlung and the structure- (and…
The decays $\tau^-\to K^-\eta\nu_\tau$ and $K^-\eta^\prime\nu_\tau$ are studied in the context of Chiral Perturbation Theory supplemented with the explicit inclusion of resonances. For the required vector-form factors we have explored three…
We present the first observation of tau lepton decays to hadronic final states with a phi-meson. This analysis is based on 401 fb^-1 of data accumulated at the Belle experiment. The branching fraction obtained is B(tau- -> phi K- nu) =…
We have searched for lepton-flavor-violating $\tau$ decays with a pseudoscalar meson ($\eta$, $\eta'$ {and} $\pi^0$) using a data sample of 401 fb$^{-1}$ collected with the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. No…
We present herein new results from Belle on the $\tau^- \rightarrow \pi^- \nu_{\rm \tau} \ell^+ \ell^- $ branching fraction and from BABAR on the $\tau^- \rightarrow K^- (0,1,2,3) \pi^0 \nu_{\rm \tau}$, $\tau^- \rightarrow \pi^- (3,4) \pi^0…
We have searched for the decay of the tau lepton into seven charged particles and zero or one pi0. The data used in the search were collected with the CLEO II detector at the Cornell Electron Storage Ring (CESR) and correspond to an…
Using data recorded by the CLEO-II detector at CESR, we report the first measurement of the branching fraction for the decay of $\tau^-$ into $K^{*-}\eta \nu_{\tau}$. The measured branching fraction is (2.9 +- 0.8 +- 0.4) $10^{-4}$. We also…
A search for the lepton-flavor-violating decay of the tau into three charged leptons has been performed using $91.5 \mathrm{fb}^{-1}$ of data collected at an $e^+e^-$ center-of-mass energy of 10.58 GeV with the BaBar detector at the PEP-II…
Based on a sample of 225.3 million J/\psi events accumulated with the BESIII detector at the BEPCII, the decays of \eta' to pi+pi-l+l- are studied via J/\psi to \gamma\eta'. A clear \eta' signal is observed in the pi+pi-e+e- mass spectrum,…
Using $(1310.6 \pm 7.0) \times 10^{6}~J/\psi$ events acquired with the BESIII detector at the BEPCII storage rings, the decay $\eta^\prime\rightarrow\pi^+\pi^-\mu^+\mu^-$ is observed for the first time with a significance of 8$\sigma$ via…