The high redshift intergalactic and interstellar media with X‐shooter

Abstract

I review here a few important questions that X-shooter can help tackle and answer in the field of quasar absorption lines. This includes (i) determine the ionizing background and the physical state of the inter-galactic medium (IGM) by analysing the characteristics of the Lyman-α forest and the proximity effect; (ii) investigate the metal content of the high redshift IGM; (iii) study the small scale transverse correlation in the IGM by observing pairs of quasars with small separation in the sky; (iv) study the galaxy-IGM relations by detecting the counterpart of damped Lyman-α systems (DLAs) or determining the correlation between the properties of galaxies and absorption lines; (v) detect and characterize the long-sought cold diffuse molecular (H2 and CO) interstellar medium (ISM) of high redshift galaxies and study its dust content.