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arXiv · 1812.08578

Observations of X-ray reverberation around black holes

B. De Marco·G. Ponti
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Abstract

The X-ray emission from accreting black hole (BH) systems displays strong variability. Short reverberation lags are expected between the primary hard X-ray continuum and the reprocessed disc emission. These lags depend on light-travel distances, thus offering the opportunity to map the geometry of the innermost accretion flow. X-ray reverberation lags have been observed in several BH accreting systems. In radio quiet active galactic nuclei (AGN) these lags scale with BH mass and point to a reprocessing region located close to the Comptonizing X-ray corona. On the other hand, reverberation lags detected in the hard state of some BH X-ray binaries (BHXRB) suggest a different accretion flow geometry than in AGN, showing evidence of evolution as a function of luminosity.

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B. De Marco, G. Ponti. 2018-12-20. Observations of X-ray reverberation around black holes. https://doi.org/10.1002/asna.201913612

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