Investigating Quasar Diversity using UV, X-ray, and Emission-line Properties
Abstract
We investigate the diversity of quasars through the analysis of their UV (Sheldon et al, these proceedings), X-ray, and emission-line properties. We concentrate on a sample of 25 radio-quiet SDSS quasars with HST observations that all have similar optical luminosities and redshifts (z~0.5). These objects fill gaps in the sample of “reverberation mapped (RM)” quasars in terms of their CIV parameter space (CIV EQW vs. CIV blueshift). In addition to exploring their UV properties, we use Chandra observations to analyze their X-ray properties (Γ, αox, Δαox), in order to determine how accretion disk winds (which are regulated by αox) contribute to the diversity of UV emission-line properties in quasars. We compare optical and X-ray derived values of L/LEdd , as Γ has been shown to be an indicator of the accretion rate. We are able to determine Γ for 7 quasars from the Chandra sample with over 100 counts. Preliminary data reduction demonstrates that all of the quasars observed with over 100 counts have similar values of αox and Δαox (averaging ~ -1.56 and ~0.42, respectively), while those below 100 counts lie within a wider, weaker range (average αox ~ -1.78, and average Δαox ~0.2). With the combined UV and X-ray data, we explore the differences between quasars and attempt to understand how/when quasars can have high L/LEdd, but show little evidence for strong winds.
- Publication:
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American Astronomical Society Meeting Abstracts #231
- Pub Date:
- January 2018
- Bibcode:
- 2018AAS...23125024B