论文标题
大麦芽云中静态分子脊的结构和动力分析
Structural and Dynamical Analysis of the Quiescent Molecular Ridge in the Large Magellanic Cloud
论文作者
论文摘要
我们介绍了LMC中四个不同区域的低J 13CO和CS观测值 - 静态分子脊,30 doradus,n159和n113,所有这些都以$ \ sim3 $ PC的分辨率为单位。区域30 DOR,N159和N113正在积极形成巨大的恒星,而分子脊几乎没有形成巨大的恒星,尽管它的分子气储量很大,并且靠近N159和30 DOR。我们使用树状图将每个区域的发射从每个区域分为分层结构,并分析这些结构的尺寸,质量和线宽。我们发现,在给定的尺寸尺寸下,脊比其他区域的动能明显低,表面密度较低,从而产生较高的病毒参数。这表明山脊没有像其他区域那样积极地形成巨大的恒星,因为它的密度较小,而不是因为过量的动能抑制了崩溃。我们还发现,这些物理条件和能量平衡在脊内有很大差异,并且这种变化似乎与距离大型恒星形成的地点(例如30 DOR中的R136)的距离无关,这是$ \ sim1 $ kpc。这些变化还显示与云中局部恒星形成活性的弱相关性。
We present a comparison of low-J 13CO and CS observations of four different regions in the LMC -- the quiescent Molecular Ridge, 30 Doradus, N159, and N113, all at a resolution of $\sim3$ pc. The regions 30 Dor, N159, and N113 are actively forming massive stars, while the Molecular Ridge is forming almost no massive stars, despite its large reservoir of molecular gas and proximity to N159 and 30 Dor. We segment the emission from each region into hierarchical structures using dendrograms and analyze the sizes, masses, and linewidths of these structures. We find that the Ridge has significantly lower kinetic energy at a given size scale and also lower surface densities than the other regions, resulting in higher virial parameters. This suggests that the Ridge is not forming massive stars as actively as the other regions because it has less dense gas and not because collapse is suppressed by excess kinetic energy. We also find that these physical conditions and energy balance vary significantly within the Ridge and that this variation appears only weakly correlated with distance from sites of massive star formation such as R136 in 30 Dor, which is $\sim1$ kpc away. These variations also show only a weak correlation with local star formation activity within the clouds.