Relation of ξ_ion with physical properties of the galaxies. The top panel indicates the relation between ξ_ion and stellar mass, while the bottom panel indicates the relation between ξ_ion and the specific star-formation rate. The symbols are the same as in Fig. 4. In the top panel, the solid red line indicates the trend from the FLARES simulation at z = 6 (Seeyave et al. 2023), and the dashed red lines indicate their 3σ scatter. In the bottom panel, the solid red line represents the trend from the simulations in Yung et al. (2020b) at z = 6. The dashed red lines are the 16th and 84th percentiles.