A Mini X-Ray Survey of Sub-DLAs; Searching for AGNs Formed in Protogalaxies

G. Chartas, V. P. Kulkarni, A. Asper

A significant fraction of the sub-damped Lyman-alpha (sub-DLA) absorption systems in quasar spectra appear to be metal-rich, many with even super-solar element abundances. This rai…