The Bipolar Outflow toward G5.89–0.39
The Bipolar Outflow toward G5.89–0.39
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走向 G5.89–0.39 的双极流出
DOI：
10.1086/510547
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发表时间：
2007
期刊：
影响因子：
--
通讯作者：
R. Crutcher
中科院分区：
文献类型：
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作者：
C. Watson;E. Churchwell;E. Zweibel;R. Crutcher
我们在CO（1→0）、13CO（1→0）、C18O（1→0）和HCO+（1→0）中进行了G5.89-0.39的高分辨率观测。我们使用13CO排放量来表征G5.89-0.39流出。人们发现，这一外流是年轻的、巨大的、强大的。我们得出的结论是：(1)出口几乎沿着视线，(2)有动力学证据表明周围星际物质被夹带到出口，(3)质量夹带率为~4 × 10-3 M☉y -1，(4)在蓝色叶片中，只有~27%的出口质量是由夹带引起的，(5)垂直于流轴的出口叶片膨胀发生在~1-10 vsound。比较了中性流出剂和电离流出剂。Watson和他的同事们预测，如果通过开尔文-亥姆霍兹剪切不稳定性的携射显著增加了流出质量，中性和电离流出示踪剂的湍流速度宽度的差异是可以测量的。我们不能断定开尔文-亥姆霍兹剪切不稳定性是导致这种夹带的物理过程，但它可能在低于我们检测极限的水平上运行。
We present high-resolution observations of G5.89-0.39 in CO(1 → 0), 13CO(1 → 0), C18O(1 → 0), and HCO+(1 → 0). We characterize the G5.89-0.39 outflow using the 13CO emission. The outflow is found to be young, massive, and powerful. We conclude that (1) the outflow is nearly along the line of sight, (2) there is dynamical evidence for entrainment of ambient interstellar material into the outflow, (3) the mass entrainment rate is ~4 × 10-3 M☉ yr-1, (4) in the blue lobe, only ~27% of the outflow mass is due to entrainment, and (5) expansion of the outflow lobes perpendicular to the flow axis is occurring at ~1-10 vsound. A neutral and ionized outflow tracer are compared. Watson and coworkers predicted that if entrainment through the Kelvin-Helmholtz shear instability adds significantly to the outflow mass, a difference in the turbulent velocity widths of neutral and ionized outflow tracers could be measurable. We cannot conclude that the Kelvin-Helmholtz shear instability is the physical process causing this entrainment, but it may operate at a level below our detection limit.