The dependence of the observed flux at t = t _edge on other parameters, such as the MBH mass (M _BH), penetration factor (β), mass outflow fraction (f _out), and wind velocity (f _v ). Here we stick to the fiducial model of a Pop III star with M _⋆ = 300M _⊙, Z = 10⁻⁵. The shaded regions, magenta and green dotted lines are the same as in Figure 8.