论文标题
通过OH 18厘米的强度异常研究的管道星云的温度结构
Temperature Structure of the Pipe Nebula Studied by the Intensity Anomaly of the OH 18 cm
论文作者
论文摘要
我们介绍了OH 18厘米过渡(1612、1665、1667和1720 MHz)的四个超细结构组件朝向丝状乌云,即管道星云,带有绿色库望远镜。对光谱进行了统计平衡分析,并准确确定了弥漫性分子气体的动力学温度。派生的温度范围从40 K到75 k。从这个结果中,我们评估了由于附近的星星$θ$ -ophiuchi的紫外光子引起的星云结构的加热效果,以及“茎”和“碗”区域的界面中可能的丝丝碰撞。在茎区域中,发现气体动力温度几乎与$θ$ -ophiuchi的表观距离无关:恒星不可见紫外线加热效果。另一方面,在两个丝状结构的界面处,气体动力学温度高达$ \ sim $ 75 k。该结果为我们提供了对管道星云中丝丝碰撞方案的额外支持。
We present observations of the four hyperfine structure components of the OH 18 cm transition (1612, 1665, 1667 and 1720 MHz) toward a filamentary dark cloud, the Pipe nebula, with the Green Bank Telescope. A statistical equilibrium analysis is applied to the spectra,and the kinetic temperature of a diffuse molecular gas surrounding dense cores is determined accurately; the derived temperature ranges from 40 K to 75 K. From this result, we assess the heating effect on the filamentarystructure of the nebula's "stem" region due to UV photons from a nearby star $θ$-Ophiuchi and a possible filament-filament collision in the interface of the "stem" and "bowl" regions. In the stem region, the gas kinetic temperature is found to be almost independent of the apparent distance from $θ$-Ophiuchi: the UV-heating effect by the star is not visible. On the other hand, the gas kinetic temperature is raised, as high as $\sim$75 K, at the interface of the two filamentary structures. This result provides us with an additional support to the filament-filament collision scenario in the Pipe nebula.