Related papers: Analysis of BaBar data for three meson tau decay m…
We analyse tau -> (3 pions) nu_tau decays within the framework of the resonance chiral theory of QCD. We have worked out the relevant Lagrangian that describes the axial-vector current hadronization contributing to these processes, and the…
We review the main components that have to be considered, within Resonance Chiral Theory, in the study of processes whose dynamics is dominated by hadron resonances. We show its application in the study of the tau -> (3 pion) nu_tau decay.
We study the phenomenology of the \tau^- \to \pi^- \nu_\tau \ell^+ \ell^- decays (\ell = e, \mu), predicting the respective branching ratios and di-lepton invariant-mass spectra. In addition to the model-independent (QED) contributions, we…
The status of the Monte Carlo programs for the simulation of tau-lepton production and decay in high-energy accelerator experiments is reviewed. In particular, the status of the following packages is discussed: (i) TAUOLA for tau-lepton…
Branching fractions of decays $\tau \to K^0 \pi^- \eta\nu_\tau$, $\tau \to K^- \pi^0 \eta\nu_\tau$, $\tau \to K^-K^0 \eta\nu_\tau$ and $\tau \to K^- \eta \eta \nu_\tau$ are calculated in the $U(3)\times U(3)$ chiral NJL quark model. The…
Three-body semileptonic $\tau$-decays offer a path to understand the properties of light hadronic systems and CP symmetry violations through searches for electric dipole moments. In studies of electro-weak physics, the hadronic part of the…
Using a data sample corresponding to an integrated luminosity of 342 $fb^{-1}$ collected with the BABAR detector at the SLAC PEP-II electron-positron storage ring operating at a center-of-mass energy near 10.58 GeV, we measure ${\cal{B}}…
With the arrival of high luminosity B-factories like the Belle II experiment, $\tau$ decay measurements have become more precise than ever, allowing rarer processes to be explored, and finer details of $\tau$ decays to be studied. These are…
Inspired by recent BESIII's amplitude analysis on $D_s^+\to\pi^+\pi^0\pi^0$, we develop a model based on the chiral unitary approach to discribe the $D_s^+\to\pi^+\pi^0\pi^0$ decay, where $D_s^+$ decays into a $\pi^+$ and a quark-antiquark…
Effective \Delta S=1 four fermion operators involving left- and right-handed currents are relevant in left-right gauge extensions of the standard model and scalar extension of the Yukawa sector. They induce K to \pi\pi\ decays which are…
We present a search for the decay B+ -> tau+ nu using 288 inverse femtobarns of data collected at the Upsilon(4S) resonance with the BaBar detector at the SLAC PEP-II B-Factory. A sample of events with one reconstructed semileptonic B decay…
We present a study of the $\tau^- \to \omega\pi^-\nu_\tau$ decay in the framework of low-energy effective field theory. By analyzing the $J^{PG}$ quantum numbers of the quark currents and the $\omega\pi$ final state, we find that only the…
Decays of scalar mesons $K^*_0(800) \to K\pi$ and $K^*_0(1430) \to K\pi, K \eta, K \eta', K_1 \pi$ are described in the extended $U(3 ) \times U(3)$ Nambu - Jona-Lasinio chiral quark model. The obtained results are in satisfactory agreement…
I discuss isospin breaking effects within the standard model. Chiral perturbation theory presents the appropriate theoretical framework for such an investigation in the low--energy range. Recent results on the electromagnetic contributions…
A chiral field theory of mesons has been applied to study the contribution of the current quark masses to the $\pi^0\rightarrow\gamma\gamma$ decay width at the next leading order. $2\%$ enhancement has been predicted and there is no new…
We use heavy vector meson $SU(2)_L \times SU(2)_R$ chiral perturbation theory to predict differential decay distributions for $\tau \rightarrow \rho \pi \nu_\tau$ and $\tau \rightarrow K^* \pi \nu_\tau$ in the kinematic region where $p_V…
Predictions for semi-leptonic decay rates of the tau lepton into two and three meson final states with one or two kaons are derived, including a discussion of K_S pi- K_S, K_L pi- K_L and K_S pi- K_L. The hadronic matrix elements are…
The BaBar collaboration has accumulated over 400 million tau-pairs which can be used to study charged leptonic and hadronic weak currents to unprecedented precision. This note presents results on lepton universality, measurements of |V_us|,…
The low-energy S-wave component of the decay $D^+ \to K^- \pi^+ \pi^+$ is studied by means of a chiral SU(3)XSU(3) effective theory. As far as the primary vertex is concerned, we allow for the possibility of either direct production of…
We report a high-statistics measurement of the branching fraction for tau^- --> pi^- pi^0 nu_tau and the invariant mass spectrum of the produced pi^- pi^0 system using 72.2 fb^-1 of data recorded with the Belle detector at the KEKB…