Axial-vector mesons from $τ\to APν_τ$ 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 $τ\to A P ν_τ$ decays, where $P$ stands for the pseudoscalar mesons $π$ or $K$. We calculate the branching ratios based in a meson dominance model. The exclusive channels $τ^-\to a_1(1260)^-π^0ν$, $τ^-\to a_1(1260)^0π^-ν$, and $τ^-\to h_1(1170)π^-ν$ turn out to be of order ${\cal O}(10^{-3})$, the channel $τ^-\to f_1(1285)π^-ν$ of order ${\cal O}(10^{-4})$, and channels $τ^-\to K_1(1270)^-π^0ν$, $τ^-\to K_1(1270)^0π^-ν$, $τ^-\to K_1(1400)^-π^0ν$, and $τ^-\to K_1(1400)^0π^-ν$ of order ${\cal O}(10^{-6})$. These results indicate that the branching ratios could be measured in experiments.

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