Schloerb F P, Snell R L, Schwartz P R
Five College Radio Astronomy Observatory, University of Massachusetts, USA.
Astrophys J. 1987 Aug 1;319(1):426-35. doi: 10.1086/165467.
We present observations of the 1300 micron continuum emission and the C18O spectral-line emission from three well-studied giant molecular cloud cores: Orion, W49, and W51. The observations were obtained at the Five College Radio Astronomy Observatory, and they provide a means to examine the consistency of these two methods to trace the column density structure of molecular clouds. We find a good general correlation between the 1300 micron continuum, which traces the column density of dust, and the C18O J = 2 --> 1 line emission, which traces the column density of molecular gas, when the effects of source temperature are taken into consideration. Moreover, nominal values for the gas and dust abundances and the dust properties reproduce the observed continuum-to-line ratios. Thus, no strong C18O abundance gradients within sources has been found, and it appears that either the C18O emission lines or the submillimeter dust emission may be used to derive the mass column density within molecular clouds accurately.
猎户座、W49和W51的1300微米连续谱发射以及C18O谱线发射的观测结果。这些观测是在五校射电天文台进行的，它们提供了一种方法来检验这两种追踪分子云柱密度结构的方法的一致性。当考虑源温度的影响时，我们发现在追踪尘埃柱密度的1300微米连续谱与追踪分子气体柱密度的C18O J = 2→1线发射之间存在良好的总体相关性。此外，气体和尘埃丰度以及尘埃特性的标称值再现了观测到的连续谱与线的比率。因此，在源内未发现强烈的C18O丰度梯度，并且似乎C18O发射线或亚毫米尘埃发射都可用于准确推导分子云内的质量柱密度。
