The Chandra Deep Fields (CDFs), being a major thrust among extragalactic X-ray surveys and complemented effectively by multiwavelength observations, have critically contributed to our dramatically improved characterization of the 0.5-8 keV cosmic X-ray background sources, the vast majority of which are distant active galactic nuclei (AGNs) and starburst and normal galaxies. In this review, I highlight some recent key observational results, mostly from the CDFs, on the AGN demography, the interactions between AGNs and their host galaxies, the evolution of non-active galaxy X-ray emission, and the census of X-ray galaxy groups and clusters through cosmic time, after providing the necessary background information. I then conclude by summarizing some significant open questions and discussing future prospects for moving forward.

中文翻译：

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钱德拉深场：揭开遥远的活动星系核和 X 射线发射星系的面纱

钱德拉深场 (CDF) 是河外 X 射线勘测中的主要推动力，并得到多波长观测的有效补充，对我们显着改善 0.5-8 keV 宇宙 X 射线背景源的表征做出了重大贡献，绝大多数它们是遥远的活动星系核（AGN）和星暴和正常星系。在这篇评论中，我重点介绍了最近的一些主要观测结果，主要来自 CDF，关于 AGN 人口统计学、AGN 与其宿主星系之间的相互作用、非活动星系 X 射线发射的演变以及 X 射线普查在提供必要的背景信息后，星系群和星系团通过宇宙时间。然后，我总结了一些重要的未决问题并讨论了未来的发展前景。