Spitzer Observations of NGC 1333: A Study of Structure and Evolution in a Nearby Embedded Cluster
Spitzer Observations of NGC 1333: A Study of Structure and Evolution in a Nearby Embedded Cluster
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DOI：
10.1086/524722
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发表时间：
2007-10
期刊：
影响因子：
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通讯作者：
R. Gutermuth;P. Myers;S. T. Megeath;L. Allen;J. Pipher;J. Muzerolle;Alicia Porras;E. Winston
中科院分区：
文献类型：
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作者：
R. Gutermuth;P. Myers;S. T. Megeath;L. Allen;J. Pipher;J. Muzerolle;Alicia Porras;E. Winston
我们提出了一个全面的结构分析，在年轻的，嵌入式集群，NGC 1333使用的成员确定斯皮策和2 MASS测光的基础上，他们的红外过量发射。总共有137个成员是以这种方式确定的，由39颗原恒星和98颗更进化的前主序星组成。在后一类中，有四个是过渡/碎片盘候选者。暴露的前主序星中有盘星的比例为83% ± 11%，显示存在可测量的无盘前主序星。在每一个I类和II类的演化状态的源被证明有非常不同的空间分布相对于其纳塔尔云的致密气体的分布。然而，这两组源之间的最近邻间距的分布被发现是非常相似的，在间距为0.045 pc处有一个强峰。径向和方位角的密度分布和表面密度图计算从确定的YSO显示，NGC 1333是细长的，而不是强烈集中，证实了以前的索赔在文献中。我们解释这些新的结果作为一个低速分散的迹象，非常年轻的集群，是不是维里平衡。
We present a comprehensive analysis of structure in the young, embedded cluster, NGC 1333 using members identified with Spitzer and 2MASS photometry based on their IR-excess emission. A total of 137 members are identified in this way, composed of 39 protostars and 98 more evolved pre-main-sequence stars with disks. Of the latter class, four are transition/debris disk candidates. The fraction of exposed pre-main-sequence stars with disks is 83% ± 11% , showing that there is a measurable diskless pre-main-sequence population. The sources in each of the Class I and II evolutionary states are shown to have very different spatial distributions relative to the distribution of the dense gas in their natal cloud. However, the distribution of nearest neighbor spacings among these two groups of sources are found to be quite similar, with a strong peak at spacings of 0.045 pc. Radial and azimuthal density profiles and surface density maps computed from the identified YSOs show that NGC 1333 is elongated and not strongly centrally concentrated, confirming previous claims in the literature. We interpret these new results as signs of a low velocity dispersion, extremely young cluster that is not in virial equilibrium.