The decay $\tau \to 3\pi\nu_\tau$ and axial-vector meson $a_1$ in the NJL model

Volkov M. K.; Nurlan K.; Pivovarov A. A

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arXiv · 2304.09454

The decay $\tau \to 3\pi\nu_\tau$ and axial-vector meson $a_1$ in the NJL model

Volkov M. K.·Nurlan K.·Pivovarov A. A

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Abstract

The branching fractions of $\tau \to \pi^+ \pi^-\pi^- \nu_\tau$ and $\tau \to \pi^- 2\pi^0\nu_\tau$ are calculated within the chiral NJL model. Features of the axial-vector $a_1$ meson which plays an important role in describing the $\tau$ decays are discussed. Permissible values for the mass and width of the $a_1$ meson are considered in accordance with the latest experiments.

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Volkov M. K., Nurlan K., Pivovarov A. A. 2023-04-19. The decay $\tau \to 3\pi\nu_\tau$ and axial-vector meson $a_1$ in the NJL model. https://arxiv.org/abs/2304.09454

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