log(ζ_ion) as function of Hα equivalent width, both of them corrected from dust attenuation. The red star represents galaxy E of B14-65666 and the green star galaxy W of B14-65666. The blue line represents the relation for galaxies at redshifts 3–7 (Prieto-Lyon et al. 2023). B14-65666 is compared with the galaxy MACS1149-JD1 (Álvarez-Márquez et al. 2024), RXCJ0600-z6-3 (Giménez-Arteaga et al. 2024), mean of 102 Lyman-break galaxies at redshift 8 (Stefanon et al. 2022), MIDIS Hα-emitters at redshifts 7–8 (Rinaldi et al. 2023), faint Lyα emitters (LAEs) at redshifts 4–5 (Lam et al. 2019), LAEs at 3.8–5 (Maseda et al. 2020), a LAE subsample at redshift 4.9 (Harikane et al. 2018), line emitters at redshifts 6.11–6.35 (Sun et al. 2023), and LAEs at redshift 6 (Ning et al. 2023). We also present the BPASS models of a binary stellar population for an instantaneous burst with ages from 1 to 20 Myr (crosses; from red to blue, the ages are 20, 16, 13, 10, 8, 6, 4, 3, 2, and 1 Myr and are connected with the solid black line) (Stanway & Eldridge 2023).