AI 中文总结
该研究基于盖亚三维尘埃图分析本地7个超云，识别出准周期性密度增强的超团，发现73%恒星形成区与之关联，超团间距特征表明其由外部压力下的超云碎裂形成，填补星际介质层级结构的尺度缺口。
AI 中文摘要
利用基于盖亚（Gaia）的太阳邻域三维尘埃图，我们分析了7个本地超云的内部结构。我们在其脊线处识别出准周期性密度增强区域，将其命名为“超团”，并发现尘埃图体积中已知恒星形成区的73%可与这些超团关联。在拥有多个已恢复超团的6个超云中，间距具有云的特征：Split超云、Malpolon超云和Vela Ridge超云的间距约为150-250秒差距，Radcliffe Wave、Natrix超云和Sagittarius Spur Extension的间距约为250-380秒差距。观测到的间距比相同有效直径的孤立自引力圆柱预测的约560秒差距小2至3倍，表明碎裂发生在外部压力下而非孤立环境中。这种重复出现的间距表明，巨分子云的形成并非局部随机过程，而是受母体超云的大尺度引力碎裂影响。无论精确形成机制如何，超团在星际介质的层级结构中占据关键的中间尺度，连接千秒差距尺度的气体带与约10-100秒差距尺度的单个巨分子云之间的空隙。
英文摘要
Using a Gaia-based 3D dust map of the solar neighborhood, we analyze the internal structure of the seven local superclouds. We identify quasi-periodic density enhancements along their spines, which we term "superclumps" and show that 73% of the known star-forming regions in the dust map volume can be associated with them. Across the six superclouds with more than one recovered superclump, the spacings are characteristic per cloud: $\sim$150-250 pc for the Split, Malpolon Cloud and Vela Ridge Cloud, and $\sim$250-380 pc for the Radcliffe Wave, Natrix Cloud and Sagittarius Spur Extension. The observed separations are two to three times smaller than the $\sim$560 pc predicted for an isolated self-gravitating cylinder of the same effective diameter, indicating fragmentation under external pressure rather than in isolation. The recurring spacing suggests that giant molecular cloud assembly is not a local, stochastic process, but is instead influenced by the large-scale gravitational fragmentation of the parent superclouds. Regardless of the precise formation mechanism, the superclumps occupy a critical intermediate scale in the hierarchical organization of the interstellar medium, bridging the gap between the kiloparsec-scale gas lanes and the $\sim$10-100 pc scale of individual giant molecular clouds.
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