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Most Supermassive Black Holes must be Rapidly Rotating

M. Elvis·G. Risaliti·G. Zamorani
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Abstract

We use the integrated spectrum of the X-ray background and quasars Spectral Energy Distribution to derive the contribution of quasars to the energy output of the Universe. We find a lower limit for the energy from accretion onto black holes of 6%, of the total luminosity of the Universe and probably more, with 15% quite possible. Comparing these values with the masses of black holes in the center of nearby galaxies we show that the accretion process must be on average very efficient: at least 15% of the accreted mass must be transformed into radiated energy. This further implies that most supermassive black holes are rapidly rotating.

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M. Elvis, G. Risaliti, G. Zamorani. 2001-12-17. Most Supermassive Black Holes must be Rapidly Rotating. https://doi.org/10.1086/339197

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