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Radiative two-pion decay of the tau lepton

A. Flores-Tlalpa·G. Lopez Castro·G. Toledo Sanchez
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Abstract

We consider the bremsstrahlung and model-dependent contributions to the radiative decay $τ^- \to π^-π^0ν_τγ$ in the context of a meson dominance model. We focus on several observables related to this decay, including the branching ratio and the photon and di-pion spectra. Particular attention is paid to the sensitivity of different observables upon the effects of model-dependent contributions and of the magnetic dipole moment of the $ρ^-(770)$ vector meson. Important numerical differences are found with respect to results obtained in the framework of chiral perturbation theory.

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A. Flores-Tlalpa, G. Lopez Castro, G. Toledo Sanchez. 2005-11-28. Radiative two-pion decay of the tau lepton. https://doi.org/10.1103/physrevd.72.113003

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