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arXiv · 2112.05617

Possible evidence for shock-cooling in the accretion flow of the luminous Seyfert galaxy PG1211+143

Ken Pounds·Andrew Lobban
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Abstract

Short-term variability and multiple velocity components in the powerful highly ionized wind of the archetypal UFO PG1211+143 are indicative of inner disc instabilities or short-lived accretion events. The recent detection of a high velocity inflow offered the first direct observational support for the latter scenario, where matter approaching at a high inclination to the black hole spin plane may result in warping and tearing of the inner accretion disc, with subsequent inter-ring collisions producing shocks, loss of rotational support and rapid mass infall. Here we identify a variable continuum component in the same data set, well-modelled by a hot thermal Comptonised spectrum that could represent cooling radiation from the shocked gas.

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Ken Pounds, Andrew Lobban. 2021-12-10. Possible evidence for shock-cooling in the accretion flow of the luminous Seyfert galaxy PG1211+143. https://arxiv.org/abs/2112.05617

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