TY - JOUR
T1 - Radiation hydrodynamics simulations of wide-angle outflows from super-critical accretion disks around black holes
AU - Hashizume, Katsuya
AU - Ohsuga, Ken
AU - Kawashima, Tomohisa
AU - Tanaka, Masaomi
N1 - Publisher Copyright:
© 2014 The Author 2014. Published by Oxford University Press on behalf of the Astronomical Society of Japan. All rights reserved.
PY - 2015/5/25
Y1 - 2015/5/25
N2 - By performing two-dimensional radiation hydrodynamics simulations with a large computational domain of 5000 times the Schwarzschild radius, we revealed that wide-angle outflow is launched via the radiation force from the super-critical accretion flows around black holes. The angular size of the outflow, where the radial velocity (vr) exceeds the escape velocity (vesc), increases with an increase of the distance from the black hole. As a result, the mass is blown away with speed of vr > vesc in all directions except for in the vicinity of the equatorial plane, θ = 0°-85°, where θ is the polar angle. The mass ejected from the outer boundary per unit time by the outflow is larger than the mass accretion rate onto the black hole, ∼ 150 LEdd/c2, where LEdd and c are the Eddington luminosity and the speed of light. The kinetic power of such wide-angle high-velocity outflow is comparable to the photon luminosity and is a few times larger than the Eddington luminosity. This corresponds to ∼ 1039-1040 erg s-1 for the stellar mass black holes. Our model is consistent with the observations of shock excited bubbles observed in some ultra-luminous X-ray sources (ULXs), supporting a hypothesis that ULXs are powered by the super-critical accretion onto stellar mass black holes.
AB - By performing two-dimensional radiation hydrodynamics simulations with a large computational domain of 5000 times the Schwarzschild radius, we revealed that wide-angle outflow is launched via the radiation force from the super-critical accretion flows around black holes. The angular size of the outflow, where the radial velocity (vr) exceeds the escape velocity (vesc), increases with an increase of the distance from the black hole. As a result, the mass is blown away with speed of vr > vesc in all directions except for in the vicinity of the equatorial plane, θ = 0°-85°, where θ is the polar angle. The mass ejected from the outer boundary per unit time by the outflow is larger than the mass accretion rate onto the black hole, ∼ 150 LEdd/c2, where LEdd and c are the Eddington luminosity and the speed of light. The kinetic power of such wide-angle high-velocity outflow is comparable to the photon luminosity and is a few times larger than the Eddington luminosity. This corresponds to ∼ 1039-1040 erg s-1 for the stellar mass black holes. Our model is consistent with the observations of shock excited bubbles observed in some ultra-luminous X-ray sources (ULXs), supporting a hypothesis that ULXs are powered by the super-critical accretion onto stellar mass black holes.
KW - Accretion, accretion disks
KW - Black hole physics
KW - ISM: jets and outflows
KW - X-rays: galaxies
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U2 - 10.1093/pasj/psu132
DO - 10.1093/pasj/psu132
M3 - Article
AN - SCOPUS:84939491093
VL - 67
JO - Publications of the Astronomical Society of Japan
JF - Publications of the Astronomical Society of Japan
SN - 0004-6264
IS - 4
M1 - 58
ER -