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arXiv · 0708.2223

Tau decay and the structure of the a1

Markus Wagner·Stefan Leupold
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Abstract

We analyse the decay $τ\toπππν$ based on the recently developed techniques to generate axial-vector resonances dynamically. Under the assumption that the a1 is a coupled-channel meson-molecule, the spectral function is described surprisingly well by adjusting only one free parameter. Including, in addition, an elementary a1 corrupts the results.

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Markus Wagner, Stefan Leupold. 2007-11-20. Tau decay and the structure of the a1. https://doi.org/10.1016/j.physletb.2008.10.025

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