A Study of Quasar Evolution in the X-Ray Band with the Aid of Gravitational Lensing

  title={A Study of Quasar Evolution in the X-Ray Band with the Aid of Gravitational Lensing},
  author={Xinyu Dai and G. Chartas and Michael Eracleous and Gordon P. Garmire},
  journal={The Astrophysical Journal},
We present results from a minisurvey of relatively high redshift (1.7 1.5, especially in the low-luminosity range between 1043 and 1045.5 ergs s-1. This result is surprising, considering that such a correlation is not found for quasars with redshifts below 1.5. We suggest that this correlation can be understood in the context of the hot-corona model for X-ray emission from quasar accretion disks, under the hypothesis that the quasars in our sample accrete very close to their Eddington limits… Expand

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