the nominal mass of the $f_1(1285)$. The results of Eq. (\[Eq:5\]) are depicted in Fig. \[Fig:2\], where in addition we plot also the result using in the numerator the nominal width of the $f_1(1285)$, $\Gamma_{f_1} = 24.1$ MeV, which will account for the decays of the $f_1(1285)$ into other channels. In the denominator of Eq. (\[Eq:5\]) we use $$\label{Eq:8}
  \Gamma_R = \Gamma_{f_1} + \Gamma_{f_1, K^* \bar K}.$$

![Production of $K^* \bar K$ induced by the excitation of the $f_1(1285)$ resonance. Dashed line: production of $f_1(1285)$ through the decay of $f_1(1285)$ into $K^* \bar K$. Solid line: through the decay of the $f_1(1285)$ into other channels.[]{data-label="Fig:2"}](fig2.eps "fig:"){width="50.00000%"}\

We observe in Fig. \[Fig:2\] the typical threshold production of a channel. However, since the production is driven by the excitation of the $f_1(1285)$, one has two factors competing, a decreasing strength of the resonance as the energy increases, and an increasing phase space for the $K^* \bar K$ production, and the product of these two factors confers the cross section a particular shape. Yet, we want to be more accurate here by taking into account that the $K^*$ will decay into $K \pi$ and the experimentalist will observe $K \pi \bar K$ at 