The Hosts of X-Ray Absorption Lines Toward AGNs

Most baryonic matter in the universe exists gaseous form and can be found structures such as galactic halos low-density intergalactic medium. proposed-ray spectroscopy missions Athena, Arcus, Lynx will have capability to identify absorption lines spectra toward bright active nuclei (AGNs), which used a tool probe this missing matter. In study, we examine optical fields surrounding 15 primary observing targets foreground galaxies galaxy groups that are potential hosts of absorption. We record basic properties host their angular physical separation from AGN line sight. This process is done by marking location various images field target plotting vs. redshift gauge proximity background source. objects according those measured redshifts require them.