Driving extreme variability: Measuring the evolving coronae and evidence for jet launching in AGN
- Creators
- Wilkins, D. R.
Abstract
Relativistically blurred reflection from the accretion disc provides a powerful probe of the extreme environments close to supermassive black holes; the inner regions of the accretion flow and the corona that produces the intense X-ray continuum. Techniques by which the geometry and extent of the corona can be measured through the observed X-ray spectrum are reviewed along with the evolution in the structure of the corona that is seen to accompany variations in the X-ray luminosity both on long and short timescales. Detailed analyses of the narrow line Seyfert 1 galaxies Mrk 335 and 1H 0707-495, over observations with XMM-Newton as well as Suzaku and NuSTAR spanning nearly a decade reveal that increases in the X-ray luminosity coincide with an expansion of the corona to cover a larger area of the inner accretion disc. Underlying this long timescale variability lie more complex patterns of behaviour on short timescales. Flares in the X-ray emission during a low flux state of Mrk 335 observed in 2013 and 2014 are found to mark a reconfiguration of the corona while there is evidence that the flares were caused by a vertical collimation and ejection of coronal material, reminiscent of an aborted jet-launching event. Measurements of the corona and reflecting accretion disc are combined to infer the conditions on the inner disc that lead to the flaring event.
Additional Information
© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.Additional details
- Eprint ID
- 67431
- Resolver ID
- CaltechAUTHORS:20160527-092024172
- Created
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2016-05-27Created from EPrint's datestamp field
- Updated
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2021-11-11Created from EPrint's last_modified field
- Caltech groups
- NuSTAR