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arXiv · 1202.0506

$\tau^{-} \to \pi^{-} \pi^{0} \nu_\tau$ decay in the extended NJL model

M. K. Volkov·D. G. Kostunin
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Abstract

The width of the decay $\tau^{-} \to \pi^{-} \pi^{0} \nu_\tau$ was calculated in the extended NJL model. Contact interaction of $W$ boson with pion pair as well as the contribution of the $\rho$ mesons in ground and first radial-exited states are taken into account. The sum of the contact diagram and diagram with intermediate $\rho$ meson in the ground state leads to the result which coincides with the result of the vector-dominance model. Our results are in satisfactory agreement with experimental data.

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M. K. Volkov, D. G. Kostunin. 2012-02-02. $\tau^{-} \to \pi^{-} \pi^{0} \nu_\tau$ decay in the extended NJL model. https://doi.org/10.1134/s1547477113010159

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