65 citations · 241 across the 10 of their papers we have counts for
Showing 2020Show all
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astro-ph.HE2020★ 42 cited
The frequency of extreme X-ray variability of radio-quiet quasars
John D. Timlin, W. Niel Brandt, Shifu Zhu +3
We analyze 1598 serendipitous Chandra X-ray observations of 462 radio-quiet quasars to constrain the frequency of extreme amplitude X-ray variability that is intrinsic to the quasa…
astro-ph.GA2020★ 1 cited
On the Fraction of X-ray Weak Quasars from the Sloan Digital Sky Survey
Xingting Pu, B. Luo, W. N. Brandt +4
We investigate systematically the X-ray emission from type 1 quasars using a sample of 1825 Sloan Digital Sky Survey (SDSS) non-broad absorption line (non-BAL) quasars with Chandra…
astro-ph.GA2020★ 34 cited
An Extreme X-ray Variability Event of a Weak-Line Quasar
Qingling Ni, W. N. Brandt, W. Yi +8
We report the discovery of an extreme X-ray flux rise (by a factor of > 20) of the weak-line quasar SDSS J153913.47+395423.4 (hereafter SDSS J1539+3954) at z = 1.935. SDSS J1539+39…