Radiatively Inefficient Accretion Flow Models of Sgr A*

被引:86
作者
Quataert, Eliot [1 ]
机构
[1] Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA
关键词
D O I
10.1002/asna.200385043
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
I review radiatively inefficient accretion flow models for the approximate to 2.6 x 10(6) M circle dot black hole (BH) in the Galactic Center. I argue for a 'concordance model' of Sgr A*: both theory and observations suggest that hot ambient gas around the BH is accreted at a rate similar to 10(-8) M circle dot yr(-1), much less than the canonical Bondi rate. I interpret Chandra observations of Sgr A* in the context of such a model: (1) the extended 'quiescent' X-ray emission is due to thermal bremsstrahlung from gas in the vicinity of the Bondi accretion radius, and (2) the similar to 10(4) second long X-ray flares are due to synchrotron or Inverse-Compton emission by non-thermal electrons accelerated in the inner similar to 10(4) Schwarzschild radii of the accretion flow.
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页码:435 / 443
页数:9
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