相关论文: Comment on $\tau$ decay puzzle

As of version 8.150 of Pythia, the isotropic decay model of tau-leptons has been replaced with sophisticated tau-lepton decay machinery. The decays and spin correlations for tau-leptons in Pythia 8 are described, including the spin…

Charged scalar particles introduced in some extensions of the standard model can induce $\tau$ leptonic decay at tree level. We find that with some charged SU(2)-singlet scalar particles, like ones introduced in Zee-type models, $\tau$…

The recent significant progress on both the experimental and theoretical sides on the study of leptonic and semileptonic kaon decays allows to precisely test the Standard Model. Here we present results for the determination of Vus from…

Many models for physics beyond the Standard Model predict lepton-flavour violating decays of charged leptons at a level which may become observable very soon. We investigate the decays of a Tau-lepton into three charged leptons (Tau ->…

One of the key assumptions of the Standard Model of fundamental particles is that the interactions of the charged leptons, namely electrons, muons, and taus, differ only because of their different masses. While precision tests comparing…

Precise measurements of the tau lepton properties provide stringent tests of the Standard Model structure and accurate determinations of its parameters. We overview the present status of a few selected topics: lepton universality, QCD tests…

We analyze the sensitivity of hadronic tau decays to non-standard interactions within the model-independent framework of the Standard Model Effective Field Theory (SMEFT). Both exclusive and inclusive decays are studied, using the latest…

We discuss predictions for the lepton-flavour changing decays Z --> e mu, mu tau, e tau which may be searched for at the Giga-Z option of the Tesla Linear Collider project with Z resonance production rates as high as 10^9. We try to be as…

Motivated by flavour symmetry models, we construct theories based on a low-energy limit featuring lepton flavour triality that have the flavour-violating decays $\tau^\pm \to \mu^\pm \mu^\pm e^\mp$ and $\tau^\pm \to e^\pm e^\pm \mu^\mp$ as…

The presence of tau leptons in the final state is an important signature in searches for physics beyond the Standard Model. Hadronically decaying tau leptons can be reconstructed over a wide kinematic range at ATLAS. The reconstruction…

We examine in detail the semi-leptonic decay $\Lambda_b \to \Lambda_c \tau{\bar \nu}_{\tau}$, which may confirm previous hints, from the analogous $B$ decay, of a new physics beyond the standard model. First of all, starting from rather…

Using a sample of 12.2 million $\tau$-lepton pairs produced by $e^+e^-$ annihilation at $\sqrt{s}\sim 10.6 $GeV and collected by the CLEO detector, we search for and set limits on CP violation in $\tau$-lepton decays. For each event, we…

We confront the indications of lepton flavor universality (LFU) violation observed in semi-tauonic $B$ meson decays with new physics (NP) searches using high $p_T$ tau leptons at the LHC. Using effective field theory arguments we correlate…

$\tau$ is playing an important role in the current B-physics indications from experiments of lepton flavor universality violations(LFUV). This suggests it be given increasing attention theoretically in the coming years, given also the fact…

The evaluation, systematic analysis and numerical study of the semileptonic $\tau$-lepton decays with two mesons in the final state has been made in the frame of the standard model extended by right handed neutrinos. In the analysis,…

We present a global analysis of leptonic and semileptonic kaon decay data, including all recent results published by the BNL-E865, KLOE, KTeV, ISTRA+ and NA48 experiments. This analysis, in conjunction with precise lattice calculations of…

We study the five-body decays $\mu^- \to e^- e^+ e^- \nu_{\mu} \bar{\nu}_{e}$ and $\tau^- \to \ell^- \ell'^+\ell'^-\nu_{\tau}\bar{\nu}_{\ell}$ for $\ell, \ell'=e, \mu$ within the Standard Model (SM) and in a general effective field theory…

We consider the possibility that the $\tau$ decay puzzle, if it is confirmed in future experiments, is a consequence of the Kobayashi-Maskawa mixing in the leptonic sector

We report the first observation of $D^+\to\tau^+\nu_\tau$ with a significance of $5.1\sigma$. We measure ${\cal B}(D^+\to\tau^+\nu_\tau) = (1.20\pm0.24_{\text{stat.}}\pm0.12_{\text{syst.}})\times10^{-3}$. Taking the world average ${\cal…

Hadronically decaying tau leptons are of prime importance in numerous physics analyses in ATLAS. The spectrum of the possible applications of hadronically decaying tau leptons reaches from Standard Model measurements, including Higgs…