Predictions of photoionization models for the absorber ABS1 with Z = Z_⊙, in the case where it is illuminated by QSO1, QSO2 (placed at 600 kpc from QSO1) and the UVB (details on the models assumptions in Appendix F). All symbols and colors are explained in the caption of Fig. F.1. Similarly to Figs. F.1 and F.3, the models in agreement with the observations are characterized by 4.1 ≲ log(T/K) ≲ 4.4 and −1.7 ≲ log U ≲ −0.7 (in Appendix F we report the detailed ranges for each plot). The metallicity is constrained to be Z >  0.3 Z_⊙.