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arXiv · 2106.02633

A Novel Test of Quasar Orientation

Gordon T. Richards·Richard M. Plotkin·Paul C. Hewett·Amy L. Rankine·Angelica B. Rivera·Yue Shen·Ohad Shemmer
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Abstract

The orientation of the disk of material accreting onto supermassive black holes that power quasars is one of most important quantities that are needed to understand quasars -- both individually and in the ensemble average. We present a hypothesis for determining comparatively edge-on orientation in a subset of quasars (both radio loud and radio quiet). If confirmed, this orientation indicator could be applicable to individual quasars without reference to radio or X-ray data and could identify some 10-20% of quasars as being more edge-on than average, based only on moderate resolution and signal-to-noise spectroscopy covering the CIV 1549A emission feature. We present a test of said hypothesis using X-ray observations and identify additional data that are needed to confirm this hypothesis and calibrate the metric.

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Gordon T. Richards, Richard M. Plotkin, Paul C. Hewett, Amy L. Rankine, Angelica B. Rivera, Yue Shen, Ohad Shemmer. 2021-06-04. A Novel Test of Quasar Orientation. https://doi.org/10.3847/2041-8213%2Fac0256

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