Anomalous component of galactic emission

被引:200
作者
Leitch, EM
Readhead, ACS
Pearson, TJ
Myers, ST
机构
[1] California Institute of Technology, 105-24, Pasadena
关键词
cosmic microwave background; dust; extinction; H II regions; supernova remnants;
D O I
10.1086/310823
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
We present results from microwave background observations at the Owens Valley Radio Observatory. These observations, at 14.5 and 32 GHz, are designed to detect intrinsic anisotropy on scales of 7'-22'. After point-source removal, we detect significant emission with temperature spectral index beta similar or equal to -2 toward the north celestial pole (NCP). Comparison of our data with the IRAS 100 mu m map of the same fields reveals a strong correlation between this emission and the infrared dust emission. From the lack of detectable H alpha emission, we conclude that the signals are consistent either with flat-spectrum synchrotron radiation or with free-free emission from T-e greater than or similar to 10(6) K gas, probably associated with a large H I feature known as the NCP Loop. Assuming beta = -2.2, our data indicate a conversion T-f/I-100 mu m, = 7.5 X 10(-2)nu(GHz)(-2.2) K (MJy sr(-1))(-1) The detection of such a component suggests that we should be cautious in any assumptions made regarding foregrounds when designing experiments to map the microwave background radiation.
引用
收藏
页码:L23 / L26
页数:4
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