THE FORMATION OF KILOPARSEC-SCALE H i HOLES IN DWARF GALAXIES
THE FORMATION OF KILOPARSEC-SCALE H i HOLES IN DWARF GALAXIES
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矮星系中千秒差距尺度黑洞的形成
DOI：
10.1088/0004-637x/738/1/10
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发表时间：
2011
期刊：
影响因子：
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通讯作者：
A. West
中科院分区：
文献类型：
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作者：
S. Warren;D. Weisz;E. Skillman;J. Cannon;J. Dalcanton;A. Dolphin;R. Kennicutt;B. Koribalski;J. Ott;A. Stilp;S. V. van Dyk;F. Walter;A. West
不规则矮星系氢原子（H i）分布中kpc尺度空穴的起源是一个有趣的问题。星星形成历史（SFHS）来自解决恒星给我们提供了独特的机会来研究过去的恒星形成事件，可能有助于塑造目前可见的H i分布。我们的样本附近的五个矮不规则星系跨越了一个数量级的总H i质量和绝对B带的幅度，是在低质量端以前研究的系统。我们使用甚大阵列H i线数据来估计在每个星系中创建中心主导洞所需的能量。我们比较这个能量估计的基础恒星种群计算SFHS来自哈勃太空望远镜的数据所释放的过去的能量。在特征年龄内释放的推断的综合恒星能量超过了我们在所有情况下创造黑洞的能量估计，假设预期的效率。因此，看来恒星反馈提供了足够的能量来产生观测到的空穴。然而，我们发现没有明显的签名的单个恒星形成事件负责观察到的结构时，比较我们的样本中的每个星系的全球SFH彼此或矮不规则星系的文献报道。在FUV或Hα成像中，我们也没有发现中心星星团的证据。我们的结论是，大的H i洞可能是形成从多代的星星形成，只有在合适的星际介质条件下。
The origin of kpc-scale holes in the atomic hydrogen (H i) distributions of some nearby dwarf irregular galaxies presents an intriguing problem. Star formation histories (SFHs) derived from resolved stars give us the unique opportunity to study past star-forming events that may have helped shape the currently visible H i distribution. Our sample of five nearby dwarf irregular galaxies spans over an order of magnitude in both total H i mass and absolute B-band magnitude and is at the low-mass end of previously studied systems. We use Very Large Array H i line data to estimate the energy required to create the centrally dominant hole in each galaxy. We compare this energy estimate to the past energy released by the underlying stellar populations computed from SFHs derived from data taken with the Hubble Space Telescope. The inferred integrated stellar energy released within the characteristic ages exceeds our energy estimates for creating the holes in all cases, assuming expected efficiencies. Therefore, it appears that stellar feedback provides sufficient energy to produce the observed holes. However, we find no obvious signature of single star-forming events responsible for the observed structures when comparing the global SFHs of each galaxy in our sample to each other or to those of dwarf irregular galaxies reported in the literature. We also fail to find evidence of a central star cluster in FUV or Hα imaging. We conclude that large H i holes are likely formed from multiple generations of star formation and only under suitable interstellar medium conditions.