| I will present a sample of 13 proximate damped Lyman-α systems (PDLAs) with redshifts between 2.5 and 3, utilizing data from the VLT/X-Shooter spectrograph. These PDLAs, selected for their strong H2 absorption near background quasars, exhibit significant NV absorption, suggesting proximity to the quasar. I will focus on CLOUDY models that provide insights into the physical conditions of the ionized gas to determine the physical conditions of the ionized gas up to the ionization front. Our conclusion is that PDLAs showing high hydrogen density and NV column density are likely situated within the quasar's environment, possibly even within the same host galaxy. Our results provide valuable insights into the co-evolution of active galactic nuclei with their host galaxies and the environments surrounding quasars. |
