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arXiv 1002.4898astro-ph.SR
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船底座星云的HST/ACS H-α成像:辐射赫比格-哈罗喷流追踪的外流活动

HST/ACS H-alpha Imaging of the Carina Nebula: Outflow Activity Traced by Irradiated Herbig-Haro Jets

Nathan Smith, John Bally, Nolan R. Walborn

摘要:

我们报告了在船底座星云中发现的新的赫比格-哈罗(HH)喷流,并讨论了一个年轻的OB星协的原恒星外流活动。这是HST/ACS对隆突进行H-alpha成像调查的第一个结果。除了之前已知的一个例子(HH 666)之外,我们还检测到21架新的HH喷气式飞机,以及17架新的候选喷气式飞机,长度从0.005到3个不等。我们得出的喷气质量损失率范围从8 e-9到1 e-6 Msun/年,但猎户座喷气质量损失率的分布比较表明,我们可能会错过一个很大的比例低于1 e-8 Msun/年的喷气。一个关键的定性结果是,即使是一些尺寸为0.01pc的最小的暗球也是正在进行的恒星形成的活跃场所,因为我们看到HH喷流从它们中出现,并且这些提供了与我们太阳系摇篮的潜在类似物,因为它们靠近数十个即将发生的超新星,这些超新星将使它们富含放射性核素,如60 Fe。HST图像显示Tr 14星团核心的突出结构,距离几颗O型星只有0.1-0.2 pc。许多弯曲喷流的例子都是“风袜”;强烈的光蒸发流可以塑造喷流,与大质量恒星的直接风和辐射竞争。最后,即使考虑到大量的喷流可能会逃脱检测,我们发现HH喷流是可以忽略不计的全球湍流的周围地区,这是由大规模的恒星反馈。

英文摘要:

We report the discovery of new Herbig-Haro (HH) jets in the Carina Nebula, and we discuss the protostellar outflow activity of a young OB association. These are the first results of an HST/ACS H-alpha imaging survey of Carina. Adding to the one previously known example (HH666), we detect 21 new HH jets, plus 17 new candidate jets, ranging in length from 0.005 to 3 pc. We derive jet mass-loss rates ranging from 8e-9 to 1e-6 Msun/yr, but a comparison to the distribution of jet mass-loss rates in Orion suggests that we may be missing a large fraction of the jets below 1e-8 Msun/yr. A key qualitative result is that even some of the smallest dark globules with sizes of 0.01pc are active sites of ongoing star formation because we see HH jets emerging from them, and that these offer potential analogs to the cradle of our Solar System because of their proximity to dozens of imminent supernovae that will enrich them with radioactive nuclides like 60Fe. HST images reveal proplyd structures in the core of the Tr14 cluster, only 0.1-0.2 pc from several O-type stars. Many examples of bent jets serve as "wind socks"; strong photoevaporative flows can shape the jets, competing with the direct winds and radiation from massive stars. Finally, even allowing for a large number of jets that may escape detection, we find that HH jets are negligible to the global turbulence of the surrounding region, which is driven by massive star feedback.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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