Feedback from Supercritical Disk Accretion Flows: Two‐dimensional Radiation‐Hydrodynamic Simulations of Stable and Unstable Disks with Radiatively Driven Outflows
Author(s) -
Ken Ohsuga
Publication year - 2007
Publication title -
the astrophysical journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.376
H-Index - 489
eISSN - 1538-4357
pISSN - 0004-637X
DOI - 10.1086/512118
Subject(s) - physics , luminosity , eddington luminosity , astrophysics , accretion (finance) , kinetic energy , outflow , supercritical fluid , energy (signal processing) , thermodynamics , quantum mechanics , galaxy , meteorology
The supercritical disk accretion flow with radiatively driven outflows isstudied based on two-dimensional radiation-hydrodynamic simulations for a widerange of the mass input rate, $\dot{M}_{\rm input}$, which is the mass suppliedfrom the outer region to the disk per unit time. The $\alpha$-prescription isadopted for the viscosity. We employ $\alpha=0.5$, as well as $\alpha=0.1$ for$\dot{M}_{\rm input}\ge 3\times 10^2L_{\rm E}/c^2$ and only $\alpha=0.5$ for$\dot{M}_{\rm input}\le 10^2L_{\rm E}/c^2$, where $L_{\rm E}$ is the Eddingtonluminosity and $c$ is the speed of light. The quasi-steady disk and radiatelydriven outflows form in the case in which the mass input rate highly exceedsthe critical rate, $\dot{M}_{\rm input}>3\times 10^2 L_{\rm E}/c^2$. Then, thedisk luminosity as well as the kinetic energy output rate by the outflowexceeds the Eddington luminosity. The moderately supercritical disk,$\dot{M}_{\rm input}\sim 10-10^2 L_{\rm E}/c^2$, exhibits limit-cycleoscillations. The disk luminosity goes up and down across the Eddingtonluminosity, and the radiatively driven outflows intermittently appear. The timeaveraged mass, momentum, and kinetic energy output rates by the outflow as wellas the disk luminosity increase with increase of the mass input rate, $\propto\dot{M}_{\rm input}^{0.7-1.0}$ for $\alpha=0.5$ and $\propto \dot{M}_{\rminput}^{0.4-0.6}$ for $\alpha=0.1$. Our numerical simulations show that theradiatively driven outflow model for the correlation between black hole massand bulge velocity dispersion proposed by \citeauthor{SR98} and\citeauthor{King03} is successful if $\dot{M}_{\rm input}c^2/L_{\rm E} \sim$ afew 10 ($\alpha=0.5$) or $\gsim$ a few ($\alpha=0.1$).Comment: 7 pages, 5 figures, accepted for publication in Ap
Accelerating Research
Robert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom
Address
John Eccles HouseRobert Robinson Avenue,
Oxford Science Park, Oxford
OX4 4GP, United Kingdom