Comparison of the UVB vs stellar photons budget, ionizing Mg⁺ in Mg²⁺. In purple we show the intrinsic BPASS model for Z = 2 Z_⊙ and age of 10^8.75 years for a constant SF stellar population. The transmitted BPASS model considering 0.7% and 14% ionizing escape fraction is shown in red and orange, respectively. The gray spectrum shows the attenuated spectrum of the group (sum of five SEDs, Sect. E.1). The dispersion of all spectra depends on the radius at which we estimate the flux, the lower and upper boundaries of the areas are for 35 and 10 kpc, respectively. The black dashed line shows the UVB from Haardt & Madau (2012) at z = 1.3.