Related papers: Study of anomalous tau lepton decay using chiral L…
The hadronic tau decay $\tau^- \to \nu_\tau \eta \pi^- \pi^0$ occurs through V-A weak current. In this decay mode, the vector current contribution is intrinsic parity violating and the axial current contribution is G parity violating. The…
We study the hadronic form factors of $\tau$ lepton decays $\tau \to K \pi(\eta) \nu$. We compute one loop corrections to the form factors using the chiral Lagrangian including vector mesons. The counterterms which subtract the divergence…
This PhD thesis studies some hadronic and radiative decays of the tau lepton using a Chiral Lagrangian including resonance fields. After a theoretical introduction, the decays to the $(\pi \pi \pi)^-$, $(KK\pi)^-$ and $\eta^{(\prime)} \pi^-…
The hadronization structure of $\tau^- \to \eta \pi^- \pi^0 \nu_\tau$ decays is analyzed using Chiral Perturbation Theory with resonances, considering only the contribution of the lightest meson resonances at leading order in the $1/N_C$…
Observables of light hadron decays are analyzed in a model of chiral Lagrangian which includes resonance fields of vector mesons. In particular, transition form factors are investigated for Dalitz decays of $V\to Pl^+l^-$ and $P\to \gamma…
We study two and three meson decays of the tau lepton within the framework of the Resonance Chiral Theory, that is based on the following properties of QCD: its chiral symmetry in the massless case, its large-N_C limit, and the asymptotic…
The \tau \to (a_1 h)^- \nu_{\tau} decays of the \tau-lepton are studied using the method of phenomenological chiral Lagrangians. The expression of weak hadronic currents between pseudoscalar and axial-vector meson states is obtained.…
In the two body hadronic tau decays, such as tau->to K pi (eta)nu, vector mesons play important role. Belle and Babar measured hadronic invariant mass spectrum of tau -> K pi nu decay. To compare the spectrum with theoretical prediction, we…
Tau decays into hadrons foresee the study of the hadronization of vector and axial-vector QCD currents, yielding relevant information on the dynamics of the resonances entering into the processes. We analyse tau -> (3 pion) nu_tau decays…
Within the resonance chiral theory, we have studied the process of a tau lepton decaying into a vector resonance plus a pseudo-Goldstone meson and a tau neutrino. Two kinds of processes are discussed: (a) tau- --> (rho pi-,omega pi-, phi…
Tau decays into hadrons have a twofold interest: On the one hand, they are a clean environment for studying the hadronization of the left-handed current of QCD, while, on the other side, provide relevant dynamical information of the…
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…
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…
Tau lepton decays with open strangeness in the final state are measured with the OPAL detector at LEP to determine the strange hadronic spectral function of the tau lepton. The decays T- ->(Kpi)-nu tau, (Kpipi)-nu tau and (Kpipipi) -nu tau…
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,…
In this work, we make a study of the $\tau^- \to \omega\pi^-\nu_\tau$ decay in the framework of low-energy effective field theory. The $J^{\mathcal{P}G}$ decompositions of the quark currents and the $\omega\pi$ final state show that,…
In a small window of phase space, chiral perturbation theory can be used to make standard model predictions for tau decays into two and three pions. For $\tau \to 2\pi \nu_\tau$, we give the analytical result for the relevant form factor…
We study direct CP violation of tau -> K pi(eta,eta')nu decays. By studying the forward and backward asymmetry, the interference of L=0 and L=1 amplitudes of the hadronic system can be extracted. By including the scalar and vector mesons…
We consider CP violating effects in the decays $\tau\rightarrow (3\pi)\nu_\tau$ where both the ${\rm J}^{\rm P}=1^+$ resonance, $a_1$, and ${\rm J}^{\rm P}=0^-$ resonance, $\pi^\prime$, can contribute. The interference between the $a_1$ and…
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…