The linear polarization of Sagittarius A*. II. VLA and BIMA polarimetry at 22, 43, and 86 GHz

被引:44
作者
Bower, GC
Wright, MCH
Backer, DC
Falcke, H
机构
[1] Natl Radio Astron Observ, Socorro, NM 87801 USA
[2] Max Planck Inst Radioastron, D-53121 Bonn, Germany
[3] Univ Calif Berkeley, Dept Astron, Berkeley, CA 94720 USA
[4] Univ Calif Berkeley, Radio Astron Lab, Berkeley, CA 94720 USA
基金
美国国家科学基金会;
关键词
galaxies : active; Galaxy : center; ISM : individual (Sagittarius A*); polarization; scattering;
D O I
10.1086/308128
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present a search for linear polarization at 22, 43, and 86 GHz from the nearest supermassive black hole candidate, Sagittarius A*. We find upper limits to the linear polarization of 0.2%, 0.4%, and 1%, respectively. These results strongly support the conclusion of our centimeter wavelength spectropolarimetry that Sgr A* is not depolarized by the interstellar medium but is in fact intrinsically depolarized.
引用
收藏
页码:851 / 855
页数:5
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