Corona or jets - The origin of X-ray emission from most RLQs
Abstract
Radio-loud quasars (RLQs) are more X-ray luminous than predicted by the X-ray-optical/UV relation for radio-quiet quasars (RQQs). The excess X-ray emission depends on the properties of radio jets. We perform large-scale archival Chandra/XMM-Newton data mining to investigate the X-ray-optical/UV-radio relation of optically selected RLQs. Model selection using information criteria supports the scenario where the disk/corona instead of the jets dominate the X-ray emission, which challenges 35 years of thinking about the basic nature of the nuclear X-ray emission of RLQs. A distinct jet component is likely important for only a small portion of flat-spectrum radio quasars. The corona-jet, disc-corona, and disc-jet connections of RLQs are likely driven by independent physical processes. Furthermore, the corona-jet connection implies that small-scale processes in the vicinity of supermassive black holes, probably associated with the magnetic flux/topology instead of black hole spin, are controlling the radio-loudness of quasars. The X-ray spectral properties and the correlation between X-ray luminosity and He II EW for RLQs also support the coronal origin.
- Publication:
-
44th COSPAR Scientific Assembly. Held 16-24 July
- Pub Date:
- July 2022
- Bibcode:
- 2022cosp...44.2000Z