The intrinsic size of Sagittarius A* from 0.35 to 6 cm

被引:124
作者
Bower, Geoffrey C. [1 ]
Goss, W. M.
Falcke, Heino
Backer, Donald C.
Lithwick, Yoram
机构
[1] Univ Calif Berkeley, Dept Astron, 601 Campbell Hall, Berkeley, CA 94720 USA
[2] Univ Calif Berkeley, Radio Astron Lab, Berkeley, CA 94720 USA
[3] Natl Radio Astron Observ, Socorro, NM 87801 USA
[4] ASTRON, NL-7990 AA Dwingeloo, Netherlands
[5] Radboud Univ Nijmegen, Dept Astrophys, NL-6500 GL Nijmegen, Netherlands
[6] Univ Toronto, CITA, Toronto, ON M5S 3H8, Canada
关键词
galaxies : active; Galaxy : center; scattering; techniques : interferometric;
D O I
10.1086/508019
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present new high-resolution observations of Sagittarius A* at wavelengths of 17.4-23.8 cm with the Very Large Array in the A configuration with the Pie Town Very Long Baseline Array (VLBA) antenna. We use the measured sizes to calibrate the interstellar scattering law and find that the major axis size of the scattering law is smaller by similar to 6% than previous estimates. Using the new scattering law, we are able to determine the intrinsic size of Sgr A* at wavelengths from 0.35 to 6 cm using existing results from the VLBA. The new law increases the intrinsic size by similar to 20% at 0.7 cm and < 5% at 0.35 cm. The intrinsic size is at 0.35 cm and is 13(-3)(+7)R(s) proportional to lambda(gamma), where gamma is in the range 1.3-1.7.
引用
收藏
页码:L127 / L130
页数:4
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