The post (http://chandra.harvard.edu/photo/2017/cdfs/ http://chandra.harvard.edu/photo/2017/cdfs/) on the Chandra site has some additional information, includin

The post (http://chandra.harvard.edu/photo/2017/cdfs/ http://chandra.harvard.edu/photo/2017/cdfs/) on the Chandra site has some additional information, including links to a couple of papers: The deepest X-ray view of high-redshift galaxies: constraints on low-rate black-hole accretion (https://arxiv.org/pdf/1608.02614v1.pdf https://arxiv.org/pdf/1608.02614v1.pdf) and THE CHANDRA DEEP FIELD-SOUTH SURVEY: 7 MS SOURCE CATALOGS (https://arxiv.org/pdf/1611.03501v2.pdf https://arxiv.org/pdf/1611.03501v2.pdf) which has some nice images overlaying X-ray sources on images closer to visual wavelengths.