The Research of Massive Star Forming Regions.

星星形成的研究是天文学领域中一个比较年轻的学科。虽然这个项目的许多数据现在已经存在，但我们还没有提出一个可行的星星形成理论。特别是对于大质量星星的形成，还有许多重要的问题没有得到解答。由于大质量星星的形成区域除了OMC 1外都很遥远，因此需要高分辨率的射电观测来研究大质量科塞。本项目观测了5个亮边分子云（NGC 281，M17，IC 1848，Orion Bright Bar，S140，IC 1848），研究了大质量星星形成的泡状模型;观测了5个大质量星星形成区，研究了原大质量恒星盘的演化。(W58，W31，W30H，ON1，W33）。对于分子云和大质量星星形成之间的联系，一个经常被引用的处方是大质量星星形成的水泡模型，其中大质量的 ...更多信息 恒星在分子云的表面上形成是外部扰动的结果。为此，我们观察到猎户座明亮的酒吧。该杆具有研究HII区与分子云相互作用的理想构型。我们发现了激波压缩层平行于电离锋的证据。然而，在冲击区的表观密度增强3是太小的辐射冲击。为了解释这种差异，我们提出了激波压缩区为块状或不均匀的模型。对M17的观测也支持这一观点。然而，我们还没有找到证据表明冲击波可以压缩物质到足以引发星星形成的程度。为了研究原恒星盘的演化，我们观察了5个大质量星星形成区。主要结果如下。1.在W58中，我们发现了一个巨大的原恒星盘，它的旋转方向与银河系的旋转方向平行。此外，^<13>CO和HCO^+排放的速度梯度也表明存在差异旋转。2.发现了细长块状构造，并在伸长方向上存在速度梯度。3.每个细长的结构都有两个或三个致密的核心。4.每个致密核具有几乎平行于细长结构的速度梯度。我们认为这种速度梯度是由于旋转引起的。根据这些结果，我们提出了一个原恒星盘演化的方案。少

The study of star formation is a relatively young descipline of the field of astronomy. Though many data to this project now exists, we have not yet produced a viable theory of star formation. Especially for massive star formation, there are many important question which remained unanswered. As the massive star forming region are very far except OMC1, high resolution radio observations are needed to study the dense corse of GMC. Recently high resolution observations are available by using 45m telescope of Nobeyama Radio Observatory. In this project we have observed 5 bright rimmed molecular clouds(NGC281,M17,IC1848,Orion Bright Bar,S140,IC1848) to study the blister model of massive star formation and 5 massive star forming regions to study the evolution of proto massive stellar disk.(W58,W31,W30H,ON1,W33) using 45 m telescope. One frequently cited prescription for a link between molecular clouds and massive star fomation is the blister model of massive star formation, in which massive … More stars form on the surfaces of molecular clouds as a result of external perturbation. For this we observed Orion bright bar. This bar has ideal configuration to study the interaction between HII region and molecular cloud. We found the evidence of shock compressed layer lying parallel to the ionization front. However the apparent density enhancement of 3 in the shocked regions is too small for a radiative shock. In order to explain this discrepancy we proposed a model that the shock compressed region are clumpy or inhomogneous. The observations of M17 also supports this picture. However we can't find the evidence that shocks can compress material enough to trigger star formation.In order to study the evolution of proto stellar disk we observed 5 massive star forming regions. Main results are as follows. 1. In W58 we found a massive proto stellar disk which rotates in a direction parallel to the galactic rotation. Also the velocity gradients of ^<13>CO and HCO^+ emissions suggests differential rotation. 2. Elongated massive structures are found and there are velocity gradient in the direction to the elongation. 3. Every elongated structure has two or three dense cores. 4. Each dense core has a velocity gradient nearly parallel to the elongated structure. We think that this velocity gradient is due to rotation. From these results, we proposed a scenario of the evolution of the proto stellar disk. Less