The clustering of C IV and Si IV at the end of reionization. A perspective from the E-XQR-30 survey

We studied the clustering of metal absorption lines and the structures that they arise in as a function of cosmic time. We focused on the behaviour of ̧iv and ionic species. These ̧iv and absorption features are identified along a given quasar sightline. We exploited the two-point correlation function (2PCF) to investigate the clustering of these structures as a function of their separation. We utilised the E-XQR-30 data to perform a novel analysis at z>5. We also drew on literature surveys (including XQ-100) of lower redshift quasars to investigate the possible evolution of this clustering towards cosmic noon (i.e. z∼ 2-3). We find no significant evolution with redshift when considering the separation of absorbers in velocity space. Since we were comparing data across a large interval of cosmic time, we also considered the separation between absorbers in the reference frame of physical distances. In this reference frame, we find that the amplitude of the clustering increases with cosmic time for both ̧iv and on scales of $