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Black Hole Masses of High-Redshift Quasars

M. Vestergaard
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Abstract

Black-hole masses of distant quasars cannot be measured directly, but can be estimated to within a factor 3 to 5 using scaling relationships involving the quasar luminosity and broad-line width. Why such relationships are reasonable is summarized. The results of applying scaling relationships to data of quasars at a range of redshifts (z <= 6.3) are presented. Luminous quasars typically have masses of order 1 billion solar masses even at the highest redshifts. The fact that such massive black holes appear as early as at z ~ 6 indicate that black holes form very early or build up mass very fast.

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M. Vestergaard. 2004-07-16. Black Hole Masses of High-Redshift Quasars. https://doi.org/10.1142/9789812702432_0092

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