The nature of linearly polarized millimeter and submillimeter emission in Sagittarius A

被引:9
作者
Liu, Siming
Qian, Lei
Wu, Xue-Bing
Fryer, Christopher L.
Li, Hui
机构
[1] Los Alamos Natl Lab, Los Alamos, NM 87545 USA
[2] Peking Univ, Dept Astron, Beijing 100871, Peoples R China
[3] Univ Arizona, Dept Phys, Tucson, AZ 85721 USA
关键词
acceleration of particles; black hole physics; Galaxy : center; plasmas; radiation mechanisms : thermal; turbulence;
D O I
10.1086/522832
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
The linearly polarized millimeter and submillimeter emission in Sagittarius A* is produced within 10 Schwarzschild radii of the supermassive black hole at the Galactic center and may originate from a hot magnetized accretion disk, where electrons are heated efficiently by turbulent plasma waves. In such a scenario, the flux density and polarization are very sensitive to the electron heating rate and the inclination angle of disk, respectively, and the major axis of the submillimeter intrinsic polarization, which is aligned with the rotation axis of the disk, is perpendicular to the major axis of the polarized near- infrared emission. In combination with MHD simulations, which study the properties of the magnetic field and viscous stresses, the current spectral and polarization measurements give tight constraints on the model parameters. Simultaneous observations will be able to test the model.
引用
收藏
页码:L127 / L130
页数:4
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