Axial-vector mesons from $\tau \to AP{\nu }_{\tau }$ decays

Abstract

Axial-vector mesons $a_1(1260)$, $f_1(1285)$, $h_1(1170)$, $K_1(1270)$, and $K_1(1400)$ can be produced in semileptonic $\tau \to AP{\nu }_{\tau }$ decays, where $P$ stands for the pseudoscalar mesons $\pi$ or $K$. We calculate the branching ratios based in a meson dominance model. The exclusive channels ${\tau }^{-}\to a_1(1260{)}^{-}{\pi }^0\nu$, ${\tau }^{-}\to a_1(1260{)}^0{\pi }^{-}\nu$, and ${\tau }^{-}\to h_1(1170){\pi }^{-}\nu$ turn out to be of order $\mathcal{O}(10^{-3})$, the channel ${\tau }^{-}\to f_1(1285){\pi }^{-}\nu$ of order $\mathcal{O}(10^{-4})$, and channels ${\tau }^{-}\to K_1(1270{)}^{-}{\pi }^0\nu$, ${\tau }^{-}\to K_1(1270{)}^0{\pi }^{-}\nu$, ${\tau }^{-}\to K_1(1400{)}^{-}{\pi }^0\nu$, and ${\tau }^{-}\to K_1(1400{)}^0{\pi }^{-}\nu$ of order $\mathcal{O}(10^{-6})$. These results indicate that the branching ratios could be measured in experiments.

Comments: 7 pages, 1 table, 1 figure, version published in PRD