6533b827fe1ef96bd1285c35
RESEARCH PRODUCT
The effect of cooling on time dependent behaviour of accretion flows around black holes
Kinsuk AcharyyaDiego MolteniSandip K. Chakrabartisubject
PhysicsShock waveOscillationbusiness.industryAstrophysics::High Energy Astrophysical PhenomenaAstrophysics (astro-ph)FOS: Physical sciencesAstronomy and AstrophysicsAstrophysics::Cosmology and Extragalactic AstrophysicsAstrophysicsAstrophysicsAccretion (astrophysics)Power density spectraSmoothed-particle hydrodynamicsGeneral Relativity and Quantum CosmologyAmplitudeSpace and Planetary SciencebusinessAstrophysics::Galaxy AstrophysicsThermal energydescription
We present the results of several numerical simulations of two dimensional axi-symmetric accretion flows around black holes using Smoothed Particle Hydrodynamics (SPH) in the presence of cooling effects. We consider both stellar black holes and super-massive black holes. We observe that due to {\it both radial and vertical oscillation} of shock waves in the accretion flow, the luminosity and average thermal energy content of the inner disk exhibit very interesting behaviour. When power density spectra are taken, quasi-periodic variabilities are seen at a few Hz and also occasionally at hundreds of Hz for stellar black holes. For super-massive black holes, the time scale of the oscillations ranges from hours to weeks. The power density spectra have a flat top behavior with average {\it rms} amplitude of a few percent and a broken power-law behavior. The break frequency is generally found to be close to the frequency where the shock oscillates.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2004-02-24 |