Rapidly Spinning Black Holes in Quasars: An Open Question

Abstract

Wang et al. (2006) estimated an average radiative efficiency of 30% -- 35% for quasars at moderate redshift. We find that their method is not independent of quasar lifetimes and thus that quasars do not necessarily have such high efficiencies. Nonetheless, it is possible to derive interrelated constraints on quasar lifetimes, Eddington ratios, and radiative efficiencies of supermassive black holes. We derive such constraints using a statistically complete sample of quasars with black hole mass estimates from broad Mg II, made both with and without the radiation pressure correction of Marconi et al. (2008). We conclude that for quasars with L/LEdd > 0.02, lifetimes can range from 140 to 750 Myr for Schwarzschild black holes. Coupled with observed black hole masses, quasar lifetimes of < 140 Myr would imply that radiatively inefficient accretion or BH mergers must be important in the accretion history of quasars. Given reasonable assumptions about the quasar population, if the average quasar lifetime is < 1 Gyr, and if radiatively inefficient accretion is unimportant, then not many BHs with Eddington ratio < 0.2 can be rapidly spinning.

14 pages, 3 figures, accepted by ApJ on Sep 2008

References in corpus (27)

• The Sloan Digital Sky Survey: Technical Summary
• Wilkinson Microwave Anisotropy Probe (WMAP) Three Year Results: Implications for Cosmology
• Energy input from quasars regulates the growth and activity of black holes and their host galaxies
• Modeling feedback from stars and black holes in galaxy mergers
• Reverberation Measurements for 17 Quasars and the Size-Mass-Luminosity Relations in Active Galactic Nuclei
• Local Supermassive Black Holes, Relics of Active Galactic Nuclei and the X-ray Background
• On the Fate of Gas Accreting at a Low Rate onto a Black Hole
• Observational constraints on growth of massive black holes
• The SDSS Quasar Survey: Quasar Luminosity Function from Data Release Three
• Black Holes, Galaxy Formation, and the M_BH-sigma Relation
• The obscured growth of massive black holes
• Biases in Virial Black Hole Masses: An SDSS Perspective
• Self-Consistent Models of the AGN and Black Hole Populations: Duty Cycles, Accretion Rates, and the Mean Radiative Efficiency
• Measuring the black hole masses of high redshift quasars
• Determining Central Black Hole Masses in Distant Active Galaxies
• Relativistic X-ray Lines from the Inner Accretion Disks Around Black Holes
• A Physical Model for the Origin of Quasar Lifetimes
• Black Hole Spin Evolution
• The evolution of massive black hole seeds
• The Evolution of Black Hole Mass and Spin in Active Galactic Nuclei
• The Sloan Digital Sky Survey Quasar Catalog III. Third Data Release
• The effect of radiation pressure on virial black hole mass estimates and the case of Narrow Line Seyfert 1 galaxies
• Spin, Accretion and the Cosmological Growth of Supermassive Black Holes
• How Much Mass do Supermassive Black Holes Eat in their Old Age?
• Evidence for Rapidly Spinning Black Holes in Quasars
• Multiepoch Sky Surveys and the Lifetime of Quasars
• Evolution of massive black holes

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• Quasinormal modes of black holes and black branes
• The Demography of Super-Massive Black Holes: Growing Monsters at the Heart of Galaxies
• Supermassive Black Hole Mass Estimates Using Sloan Digital Sky Survey Quasar Spectra at 0.7 < z < 2