Related papers: The tau leptons theory and experimental data: Mont…
The article describes the identification of hadronically decaying tau leptons in ppbar collisions at 1.96 TeV collected by the DZero detector at the Fermilab Tevatron. After a brief description of the motivations and the challenges of…
Three important QCD-related aspects of the $\tau$ and $\mu$ dynamics are reviewed: the determination of the strong coupling from the hadronic tau decay width, leading to the updated value $\alpha_s(m_\tau^2) = 0.331 \pm 0.013$; the…
This is a review of new results on the Tau lepton. The lifetime has been measured with improved precision, allowing the test of lepton universality to 0.2% level. There are several new measurements of the branching ratios for the hadronic…
A description of three body tau decays with general vectorial and derivative (non-minimal) couplings is presented for experiments where the tau direction of flight is not reconstructed. The proposed interactions may be due to charged…
We review many of the contributions of the CLEO experiment to tau physics. Topics discussed are: branching fractions for major decay modes and tests of lepton universality; rare decays; forbidden decays; Michel parameters and spin physics;…
We analyze the $\tau^-\to(K\pi)^-\nu_\tau$ decays within an effective field theory description of heavy new physics (NP) modifying the SM left-handed weak charged current and include refined SM input for the participant meson form factors…
An updated measurement of alpha_s(m_tau) from ALEPH tau hadronic spectral functions is presented. We report a study of the perturbative prediction(s) showing that the fixed-order perturbation theory manifests convergence or principle…
Top quark pair decay events resulting in final states containing {\tau} leptons present interesting channels in the search for physics beyond the Standard Model. This document describes the in-progress analyses of two channels, {\tau}+jets…
We report some new results on tau decays obtained by the BaBar collaboration using 468 inverse femtobarn of electron-positron collisions recorded at the PEP-II asymmetric collider at Stanford Linear Accelerator Center. First We will show…
The Michel parameters of the leptonic tau decays are measured using the OPAL detector at LEP. The Michel parameters are extracted from the energy spectra of the charged decay leptons and from their energy-energy correlations. A new method…
We perform a global analysis of exclusive hadronic tau decays into one and two mesons using the low-energy limit of the Standard Model Effective Field Theory up to dimension six, assuming left-handed neutrinos. A controlled theoretical…
Motivated by the recent investigation of neutrinoless $\tau$-lepton decays by the CLEO collaboration, we perform a systematic analysis of such decays in a possible new-physics scenario with heavy Dirac/Majorana neutrinos, including…
A preliminary measurement of the branching fraction of the tau- -> 3h-2h+nu decay (h= pi, K$) with the BaBar detector is found to be {8.52 +/- 0.09 +/- 0.40} x 10E-4, where the first error is statistical and the second is systematic. The…
We have studied hadronic tau decay modes involving an eta meson using 490 fb^{-1} of data collected with the Belle detector at the KEKB asymmetric-energy e+e- collider. The following branching fractions have been measured: B(tau- -> K- eta…
The talk covers three contributions on (i) the final measurement of branching ratios and spectral functions of t decays using the full LEP-I data from ALEPH, (ii) a preliminary measurement of the t hadronic branching ratios from DELPHI and…
We give a pedagogical introduction to the rich phenomenology of hadronic tau decays. These decays provide a unique window into the interplay of electroweak and strong interactions at low energies, as they occur primarily via $W$ exchange…
The experimental information on b --> s l^+ l^- decays has grown enormously during the last couple of years due to BaBar, Belle, CDF and LHCb. Especially, exclusive modes B --> K^(*) l^+ l^-, which have the largest rate and are easily…
We analize the current data on $\tau$-lepton decays and show that they are consistent with the Standard Model
The present experimental status of searches for lepton flavor violating decays of the $\tau$ lepton to a lighter mass lepton and a photon or a pseudoscalar meson is presented. The results obtained are from $e^+e^-$ annihilation data…
Results on semi-hadronic decays of the $\tau$ lepton are presented, from studies of $e^+e^-$ annihilation data obtained at the Cornell Electron Storage Ring with the CLEO-II detector. Branching fractions have been measured for decays to…