Open AccessProperties of accretion shock waves in viscous flows around black holes
Author(s) -
Chakrabarti Sandip K.,
Das Santabrata
Publication year - 2004
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2004.07536.x
Subject(s) - physics , shock wave , parameter space , shock (circulatory) , oscillation (cell signaling) , accretion (finance) , viscosity , mechanics , astrophysics , flow (mathematics) , classical mechanics , angular momentum , geometry , thermodynamics , medicine , mathematics , biology , genetics
Accretion flows having low angular momentum and low viscosity can have standing shock waves. These shocks arise because of the presence of multiple sonic points in the flow. We study the region of the parameter space in which multiple sonic points occur in viscous flows in the absence of cooling. We also separate the parameter space into regions allowing steady shocks and oscillating shocks. We quantify the nature of two critical viscosities which separate the flow topologies. The post‐shock region being hotter, it emits harder X‐rays and oscillating shocks cause oscillating X‐ray intensities giving rise to quasi‐periodic oscillations. We show that with the increase in viscosity parameter, the shock always moves closer to the black hole. This implies an enhancement of the quasi‐periodic oscillation frequency as viscosity is increased.