What is hatching in the egg?

被引:35
作者
Jura, M
Turner, JL
Van Dyk, S
Knapp, GR
机构
[1] Univ Calif Los Angeles, Dept Phys & Astron, Los Angeles, CA 90095 USA
[2] Princeton Univ Observ, Princeton, NJ 08544 USA
基金
美国国家航空航天局; 美国国家科学基金会;
关键词
radio continuum : ISM; stars : AGB and post-AGB;
D O I
10.1086/312437
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We report VLA detections at 1.3, 2, and 3.6 cm of the Egg Nebula, RAFGL 2688. We resolve the source and find an inner 9 " diameter core that is produced by similar to 0.01 M. of dust. It seems that the Egg Nebula experienced a major mass ejection, losing similar to 1 M. during the past less than or equal to 1200 yr. The centimeter-wavelength emission is extended at a position angle of 53 degrees, while the famous jets and lobes in the Egg Nebula Lie along a position angle of 15 degrees. The multiple symmetries in the Egg Nebula may occur because the rotation axis of the mass-losing star is not perpendicular to the orbital plane of the putative close binary. Between 3.6 cm and 350 mu m, the dust opacity appears to vary as nu(0.6), which can be explained if there are some grains with sizes at least as large as 0.5 cm.
引用
收藏
页码:L105 / L108
页数:4
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