I study the VLA H I survey of H II galaxies by Taylor et al. and the VLA H I survey of low surface brightness (LSB) dwarf galaxies by Taylor et al. to investigate the role of galaxy interactions in triggering the bursts of massive star formation seen in H II galaxies. Comparing the two surveys, I find that H II galaxies have companions more than twice as often as LSB dwarfs (p = 0.57 for H II galaxies, compared to p = 0.24 for LSB dwarfs). I examine the completeness of the companion samples detected by the two surveys. For the companions to H II galaxies, the sample is likely complete in the distribution of velocity separations from their parent galaxies but is probably missing some companions at large projected linear separations because of the finite size of the VLA primary beam. For the companions of LSB dwarfs, the small number of detections means their distributions in velocity and linear separation are poorly determined, but the LSB dwarfs were observed with the same observational setup as the H II galaxies, so they will have the same levels of completeness. Because the two samples were observed in exactly the same fashion, there will be no relative bias in the number of companions introduced in this way. In addition, the redshift distributions of the two samples are very similar, so there will not be a distance-related relative bias. Thus, I conclude that the difference in the number of H I rich companions is genuine, and signifies a difference in the local, small-scale environments between the two types of galaxy. I search through published galaxy catalogs to determine number of neighbors each galaxy has outside the area of the VLA observations. At these large separations, the number of neighbors is the same, within the errors, for the two types of galaxy. The high rate of companion occurrence at low separations for H II galaxies relative to LSB dwarfs supports the hypothesis that the bursts of star formation are triggered by galaxy interactions.
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机译：我研究了Taylor等人对H II星系的VLA H I调查。 Taylor等人的VLA H I对低表面亮度（LSB）矮星系的调查。调查星系相互作用在触发H II星系中看到的大规模恒星形成爆发中的作用。比较这两个调查，我发现H II星系的伴星是LSB矮星的两倍多（H II星系的p = 0.57，而LSB矮星的p = 0.24）。我检查了两次调查检测到的同伴样本的完整性。对于H II星系的伴星来说，样品与母星系的速度间隔分布可能很完整，但由于VLA主光束的大小有限，所以可能缺少一些大投影线性间隔的伴星。对于LSB矮星的伴星来说，少量的探测意味着它们在速度和线性间隔上的分布很难确定，但是LSB矮星的观测设置与H II星系相同，因此它们具有相同的完整性水平。由于以完全相同的方式观察了两个样本，因此以这种方式引入的同伴数量不会有相对偏差。另外，两个样本的红移分布非常相似，因此不会存在与距离相关的相对偏差。因此，我得出结论，富含H I的同伴数量上的差异是真实的，并表明这两种星系在局部的小规模环境中存在差异。我搜索已发布的星系目录，以确定每个星系在VLA观测范围之外的邻居数量。在这些较大的间隔中，两种星系在误差范围内的邻居数相同。相对于LSB矮星，H II星系在低间隔时伴生的发生率很高，这支持了恒星形成的爆发是由星系相互作用触发的假设。
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