The branching fraction of $\tau \to K^{⁎-}(892)\eta {\nu }_{\tau }$ was calculated in the Nambu–Jona-Lasinio model in the mean field approximation, which corresponds to considering quark loops in the leading order of $1/N_c$. Four channels were taken into account: the contact channel (the final states are directly producted from the lepton current without any intermediate meson states), the axial-vector channel with two intermediate physical states $K_1(1270)$ and $K_1(1400)$, the vector channel with intermediate $K^{⁎}(892)$ meson and the pseudoscalar channel with intermediate K meson. It is shown that the first two channels give the dominant contribution to the decay width. Of the remaining two channels, the pseudoscalar channel plays a more prominent role. The final result is in satisfactory agreement with experimental data. A prediction for the differential decay width is presented.

的分支分数 $\tau \to {ķ}^{⁎-}（892）\eta {\nu }_{\tau }$ 是在Nambu–Jona-Lasinio模型中以平均场近似值计算的，它对应于以 $\mathrm{1个}/{ñ}_C$。考虑了四个通道：接触通道（最终状态是直接由轻子电流产生的，没有任何中间介子状态），轴向矢量通道具有两个中间物理状态${ķ}_{\mathrm{1个}}（1270）$ 和 ${ķ}_{\mathrm{1个}}（1400）$，中间的向量通道 ${ķ}^{⁎}（892）$介子和带有中间K介子的伪标量通道。结果表明，前两个通道对衰减宽度起主要作用。在其余两个通道中，伪标量通道扮演着更为重要的角色。最终结果与实验数据令人满意。给出了差分衰减宽度的预测。