An alternative to spinning dust for the microwave emission of LPH 201.663+1.643: An ultracompact HII region

被引:8
作者
McCullough, PR [1 ]
Chen, RR [1 ]
机构
[1] Univ Illinois, Dept Astron, Urbana, IL 61801 USA
关键词
cosmic microwave background; diffuse radiation; dust; extinction; HII regions; ISM : clouds; radiation mechanisms : thermal; radio continuum : ISM;
D O I
10.1086/339473
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
The microwave spectral energy distribution of the dusty, diffuse H II region LPH 201.663+1.643 has been interpreted by other authors as tentative evidence for microwave emission from spinning dust grains. We present an alternative interpretation for that particular object, specifically, that an ultracompact H II region embedded within the dust cloud would explain the available observations as well or better than spinning dust. Parameters for the size, surface brightness, and flux density of the putative ultracompact H II region, derived from the microwave observations, are within known ranges. A possible candidate for such an ultracompact H II region is IRAS 06337+1051, based on its infrared colors. However, the infrared flux of IRAS 06337+1051 appears to be too small to be consistent with the microwave flux required for this alternative model to explain the observations.
引用
收藏
页码:L45 / L48
页数:4
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