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Viscous dissipative two-temperature accretion flows around black holes


General relativistic, advective, viscous, two-temperature accretion disc solutions are studied around a Schwarzschild black hole. The thermodynamics of the flow is described by the relativistic equation of state or Chattopadhyay and Ryu equation of state modified for a two-temperature regime. The cooling processes considered are bremsstrahlung, synchrotron and the Comptonization of these photons. The degeneracy of accretion solutions in the two-temperature regime is resolved using the so called ‘maximum entropy’ methodology. Utilizing this method, we analyzed the unique solutions and the corresponding spectra for a broad range of parameter space. Interplay between heating due to viscous dissipation and cooling due to different radiation mechanisms plays a significant role in determining the solution and spectrum obtained. In the end, we analyze the observation of a low luminosity AGN, NGC 3998, fitted using our model.

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We thank the anonymous referee for giving suggestions which improved the quality of the paper further.

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This article is part of the Special Issue on “Astrophysical Jets and Observational Facilities: A National Perspective”.

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SARKAR, S., CHATTOPADHYAY, I. Viscous dissipative two-temperature accretion flows around black holes. J Astrophys Astron 43, 34 (2022).

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  • Accretion—two-temperature—black holes—accretion discs—shocks