Detecting and Characterizing Young Quasars. II. Four Quasars at z ∼ 6 with Lifetimes < 104 Yr

  title={Detecting and Characterizing Young Quasars. II. Four Quasars at z ∼ 6 with Lifetimes < 104 Yr},
  author={Anna-Christina Eilers and Joseph F. Hennawi and Frederick B. Davies and Robert A. Simcoe},
  journal={The Astrophysical Journal},
The extents of proximity zones of high-redshift quasars enable constraints on the timescales of quasar activity, which are fundamental for understanding the growth of the supermassive black holes (SMBHs) that power the quasars’ emission. In this study, we obtain precise estimates for the ultraviolet (UV) luminous lifetimes of 10 quasars at 5.8 < z < 6.5. These objects were preselected to have short lifetimes based on preliminary measurements of their proximity zone sizes and were then targeted… Expand
Estimating the Effective Lifetime of the z ∼ 6 Quasar Population from the Composite Proximity Zone Profile
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Extreme Variability and Episodic Lifetime of Quasars
  • Yue Shen
  • Physics
  • The Astrophysical Journal
  • 2021
We constrain the average episodic quasar lifetime (as in steady-state accretion) using two statistics of quasars that are recently turned off (i.e., dimmed by a large factor): (1) the fraction ofExpand


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