论文标题
云云碰撞作为G31.41+0.31大量原始群集的起源
Cloud-cloud collision as origin of the G31.41+0.31 massive protocluster
论文作者
论文摘要
G31.41+0.31（G31）热分子芯（HMC）是一种高质量原始簇，显示出在高角度分辨率下进行良好研究的加速插入和旋转旋转。为了补充G31中小规模的准确视野，我们通过执行N $ _2 $ H $^+$ \，（1--0）观察到IRAM 3000万望远镜的区域的$ \ sim $ 6 $ 6 $ \ times6 $ \，arcmin $^2 $^2 $^2 $^hmc hmmc the n $ _2 $ h $^+$ \，（1--0）观察到了大规模材料的运动学。 N $ _2 $ h $^+$ $观察结果表明，至少四个丝状臂和一个NNE-SSW速度梯度（$ \ sim $ 0.4 \，km/s/pc）组成的大规模（5 \，PC）集线器系统（HFS）。线宽向HFS中心的集线器增加，在中央1 \，PC中达到2.5--3 \，km \，s $^{ - 1} $。大规模速度梯度的起源可能是云云碰撞。在这种情况下，G31中的细丝将是由碰撞和在1000 \尺度上观察到的HMC旋转产生的压缩形成的，Au会由剪切造成的剪切引起，这是由云云碰撞在几个PC的尺度上引起的。我们得出的结论是，G31代表压缩层中的HFS，其与天空平面的正交取向，并代表了恒星形成的细丝到群体范式的基准。
The G31.41+0.31 (G31) hot molecular core (HMC) is a high-mass protocluster showing accelerated infall and rotational spin-up that is well studied at high-angular resolution. To complement the accurate view of the small scale in G31, we have traced the kinematics of the large-scale material by carrying out N$_2$H$^+$\,(1--0) observations with the IRAM 30m telescope of an area of $\sim$6$\times6$\,arcmin$^2$ around the HMC. The N$_2$H$^+$ observations have revealed a large-scale (5\,pc) hub-filament system (HFS) composed by at least four filamentary arms and a NNE--SSW velocity gradient ($\sim$0.4\,km/s/pc) between the northern and southern filaments. The linewidth increases towards the hub at the center of the HFS reaching values of 2.5--3\,km\,s$^{-1}$ in the central 1\,pc. The origin of the large-scale velocity gradient is likely cloud-cloud collision. In this scenario, the filaments in G31 would have formed by compression resulting from the collision and the rotation of the HMC observed at scales of 1000\,au would have been induced by shear caused by the cloud-cloud collision at scales of a few pc. We conclude that G31 represents a HFS in a compressed layer with an orthogonal orientation to the plane of the sky, and represents a benchmark for the filaments-to-clusters paradigm of star formation.
