Zhu Liu

TL;DR: In this article, the authors constrain the evolution of active galactic nuclei (AGNs) as a function of obscuration using an X-ray-selected sample of ~2000 AGNs from a multi-tiered survey including the CDFS, AEGIS-XD, COSMOS and XMM-XXL fields.

TL;DR: In this paper, the authors constrain the evolution of AGN as a function of obscuration using an X-ray selected sample of $sim2000$ AGN from a multi-tiered survey including the CDFS, AEGIS-XD, COSMOS and XMM-XXL fields.

TL;DR: MPG-CAS Joint Doctoral Promotion Programme (CASJDP), NSFC [11273027, 11303046], Strategic Priority Research Program 'The Emergence of Cosmological Structures' of the Chinese Academy of Sciences (XDB09000000), European Union [383549], Greek Government; ESA Member States; NASA; Alfred P. Sloan Foundation; National Science Foundation; U.S. Department of Energy Office of Science; University of Arizona; Brazilian Participation Group; Brookhaven National Laboratory; Carnegie Mellon University; Universityof Florida; University Of

TL;DR: Abramowicz, Kluźniak, McClintock and Remillard as discussed by the authors showed that the 3:2 pairs of frequencies of BH high-frequency quasi-periodic oscillations scale inversely with the BH masses and that the scaling covers the entire range from stellar to supermassive BHs.

TL;DR: In this paper, the ensemble property of the Fe K$\alpha$ emission line in NLS1s is investigated by stacking the X-ray spectra of a large sample of 51 galaxies observed with XMM-Newton.