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arXiv · 1504.03111

The decay $τ\to (π, π') ν_τ$ in the Nambu - Jona-Lasinio model

A. I. Ahmadov·M. K. Volkov
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Abstract

In the Nambu - Jona-Lasinio model the decay widths $τ\to (π, π'(1300)) ν_τ$ were calculated. For the calculation of the decay width $τ\to πν_τ$ the standard NJL model was used with taking into account the intermediate axial-vector meson and the extended Nambu - Jona-Lasinio model with the intermediate $a_1(1260)$ and $a_1'(1647)$ mesons. These results are in good agreement with each other. For the calculation of the decay width $τ\to π' ν_τ$ extended Nambu - Jona-Lasinio model was used. The results are in satisfactory agreement with the experimental data. Numerical estimates for the constant $F_π$ and $F_{π'}$ are also in satisfactory agreement with both the experimental values for $F_π$ and the results obtained by calculations on the lattice.

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A. I. Ahmadov, M. K. Volkov. 2015-06-04. The decay $τ\to (π, π') ν_τ$ in the Nambu - Jona-Lasinio model. https://arxiv.org/abs/1504.03111

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