Near-Infrared Spectroscopy of Candidate Members of the Galactic Cluster [BDS2003] 107
Near-Infrared Spectroscopy of Candidate Members of the Galactic Cluster [BDS2003] 107
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DOI：
10.1086/527403
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发表时间：
2008-02
影响因子：
3.5
通讯作者：
M. Hanson;B. F. Bubnick
中科院分区：
文献类型：
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作者：
M. Hanson;B. F. Bubnick
我们提出了新的近红外分类光谱的9个候选成员的星系团[BDS 2003] 107（集群107）所观察的IRTF SpeX仪器。我们可以在光谱学上将至少三个成员分类，其中两个已经发表了2MASS光度学。这两颗恒星提供了年轻星团的近似年龄（≥106年）、距离（≤ 2 kp c）和灭绝（AV 23）的初步值。根据我们已经确定的最亮成员的性质，在表面上，107星团似乎与研究得很好的猎户座星团非常相似。我们发现了一个中O型矮星星星和一些早期B型恒星，沿着有大量的年轻恒星（YSO）。大质量YSO星星63在短K波段同时显示出早B光谱分类，CO带头发射在2.3 μm。这个大质量的YSO看起来类似于在银河系中年轻的大质量星团中看到的其他发光的CO发射物体，并为即使是相当大质量的恒星周围也存在星周盘提供了额外的证据。几个先前确定的无线电源，可能与非常早期的星星形成有关，位于这个领域，其中三个似乎有近红外对应物，我们用SpeX采集相机获得的图像中检测到。
We present new near-infrared classification spectra for nine candidate members of the galactic cluster [BDS2003] 107 (Cluster 107) observed with the IRTF SpeX instrument. We can spectroscopically classify at least three members, two of which have published 2MASS photometry. These two stars provide preliminary values for the approximate age (≥106 yr), distance ( ≤ 2 kp c ), and extinction (AV ∼ 23) of the young cluster. Based on the properties of the brightest members we have identified, on the surface Cluster 107 appears to be very similar to the well-studied Orion cluster. We find a single mid-O dwarf star and a number of early-B stars, along with massive young stellar objects (YSOs) in the field. The massive YSO Star 63 shows simultaneously an early-B spectral classification in the short K -band with CO band-head emission at 2.3 μm. This massive YSO looks similar to other luminous CO emission objects seen in young, massive clusters through out the Galaxy and provides additional evidence for the existence of circumstellar disks around even fairly massive stars. Several previously identified radio sources, presumably associated with very early star formation, lie within this field, three of which appear to have near-infrared counterparts as detected in images we obtained with the SpeX acquisition camera.