BIMA and JCMT spectropolarimetric observations of the CO J=2-1 line towards Orion KL/IRc2

被引:14
作者
Girart, JM [1 ]
Greaves, JS
Crutcher, RM
Lai, SP
机构
[1] Univ Barcelona, Dept Astron & Meteorol, Barcelona, Spain
[2] Royal Observ, Edinburgh EH9 3HJ, Midlothian, Scotland
[3] Univ Illinois, Dept Astron, Urbana, IL 61801 USA
[4] CALTECH, Jet Prop Lab, Pasadena, CA USA
关键词
polarization; magnetic fields; Orion KL/IRc2;
D O I
10.1023/B:ASTR.0000045007.35868.17
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present results of JCMT and BIMA CO J = 2 - 1 polarization observations towards the Orion KL/IRc2 high mass star forming region. The linear polarization fraction of the JCMT CO J = 2 - 1 spectra presents a clear decrease towards the center of the line, as expected, due to the increase of the optical depth. The position angle remains constant along the spectral line, except at the line center, where the highest optical depth and lower fractional polarization are measured. The combined BIMA and JCMT maps of the redshifted and blueshifted CO emission show a uniform polarization pattern that does not coincide with previous dust continuum observations at similar angular resolution. This suggests that the CO and dust are tracing different spatial components along the line of sight.
引用
收藏
页码:119 / 125
页数:7
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