INFLOW-OUTFLOW MODEL WITH CONDUCTION AND SELF-CONSISTENT FEEDING FOR Sgr A*

被引:74
作者
Shcherbakov, Roman V. [1 ]
Baganoff, Frederick K. [2 ]
机构
[1] Harvard Smithsonian Ctr Astrophys, Cambridge, MA 02138 USA
[2] MIT, Ctr Space Res, Cambridge, MA 02139 USA
关键词
accretion; accretion disks; conduction; Galaxy: center; stars:; winds; outflows; SUPERMASSIVE BLACK-HOLE; GALACTIC-CENTER; CENTRAL PARSEC; SPHERICAL ACCRETION; FARADAY-ROTATION; HOT GAS; STELLAR; STARS; SIMULATIONS; EMISSION;
D O I
10.1088/0004-637X/716/1/504
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We propose a two-temperature radial inflow-outflow model near Sgr A* with self-consistent feeding and conduction. Stellar winds from individual stars are considered to find the rates of mass injection and energy injection. These source terms help to partially eliminate the boundary conditions on the inflow. Electron thermal conduction is crucial for inhibiting the accretion. Energy diffuses out from several gravitational radii, unbinding more gas at several arcseconds and limiting the accretion rate to <1% of Bondi rate. We successfully fit the X-ray surface brightness profile found from the extensive Chandra observations and reveal the X-ray point source in the center. The super-resolution technique allows us to infer the presence and estimate the unabsorbed luminosity L approximate to 4 x 1032 erg s(-1) of the point source. The employed relativistic heat capacity and direct heating of electrons naturally lead to low electron temperature T-e approximate to 4 x 1010 K near the black hole. Within the same model, we fit 86 GHz optically thick emission and obtain the order of magnitude agreement of Faraday rotation measure, thus achieving a single accretion model suitable at all radii.
引用
收藏
页码:504 / 509
页数:6
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