The black hole spins of quasars. Issue Volume 10:Issue S312(2014) (7th March 2016)

• Record Type: Journal Article
• Authors: You, Bei; Cao, Xinwu
• Editors: Meiron, Y.; Li, S.; Liu, F.-K.; Spurzem, R.
• Is Part Of: Proceedings of the International Astronomical Union. Volume 10:Issue S312(2014)
• Page Start: 143
• Page End: 144
• Publication Date: 2016-03-07
• Subjects: galaxies: nuclei, -- galaxies: kinematics and dynamics, -- methods: numerical; Astronomy -- Congresses; Astronomy -- Periodicals; 520
• DOI: 10.1017/S1743921315007747
• Languages: English
• ISSNs: 1743-9213

Abstract

Abstract: We present the estimates of the black hole spins of five quasars. The peaks of the spectra of the accretion discs surrounding massive black holes in quasars are in the far-UV or soft X-ray band, which are usually not observed. However, in the disc corona model, the soft photons from the disc are Comptonized to high energy in the hot corona, and the hard X-ray spectra (luminosity and spectral shape) contain the information of the incident spectra from the disc. The values of black hole spin parameter a are inferred from the spectral fitting, which spread over a large range, ~ −0.94 to 0.998.