High-Resolution Studies of the Multiple Core Systems toward Cluster-forming Regions Including Massive Stars
High-Resolution Studies of the Multiple Core Systems toward Cluster-forming Regions Including Massive Stars
复制标题
对包括大质量恒星在内的星团形成区域的多核心系统的高分辨率研究
DOI：
10.1086/590146
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
F.
中科院分区：
文献类型：
--
作者：
Saito;H.;Saito;M.;Yonekura;Y.;Nakamura;F.
我们提出的C18 O观测结果的Nobeyama毫米阵列对致密的团块半径为1.03秒差距在6个星团形成的地区，包括大质量（原）星。我们确定了171个核心，其半径，线宽和分子量范围从0.01至0.09 pc，0.43至3.33 km s-1，和0.5至54.1 M的，分别。一个丛中存在许多不同线宽的核心，并且核心和亲本丛的线宽-半径关系的指数在丛中的核心与核心之间不同。这表明湍流运动的耗散程度对于一个团中的每个核是不同的。虽然核的质量随着线宽的增加而增加，但大多数核受到外部压力的重力约束。此外，随着离团簇中心的距离的增加，核的线宽和外压趋于减小，这种依赖性可能是团簇内部H2密度结构影响核的物理性质所致。此外，核心的数密度和年轻（原）星的数密度与团簇的平均H2密度有类似的关系。因此，我们的研究结果表明，集团的形成，在集团通过形成这样的多个核心，其物理性质将有很强的相关性的H2密度结构和湍流运动的集团。
We present the results of C 18 O observations by the Nobeyama Millimeter Array toward dense clumps with radii of∼ 0.3 pc in six cluster-forming regions including massive (proto) stars. We identified 171 cores, whose radius, line width, and molecular mass range from 0.01 to 0.09 pc, 0.43 to 3.33 km s–1, and 0.5 to 54.1 M⊙, respectively. Many cores with various line widths exist in one clump, and the index of the line width-radius relationship of the cores and the parental clump differs from core to core in the clump. This indicates that the degree of dissipation of the turbulent motion varies for each core in one clump. Although the mass of the cores increases with the line width, most cores are gravitationally bound by the external pressure. In addition, the line width and the external pressure of the cores tend to decrease with the distance from the center of the clump, and these dependencies may be caused by the inner H 2 density structure of the clump that affects the physical properties of the cores. Moreover, the number density of the cores and the number density of young (proto) stars have a similar relationship to the average H 2 density of the clumps. Thus, our findings suggest that the cluster is formed in the clump through the formation of such multiple cores, whose physical properties would have been strongly related to the H 2 density structure and the turbulent motion of the clump.