Magnetized filamentary gas flows feeding the young embedded cluster in Serpens South
Magnetized filamentary gas flows feeding the young embedded cluster in Serpens South
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DOI：
10.1038/s41550-020-1172-6
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发表时间：
2020-08
期刊：
影响因子：
14.1
通讯作者：
T. Pillai;D. Clemens;S. Reissl;P. Myers;J. Kauffmann;E. Lopez-Rodriguez;F. Alves;G. Franco;J. Henshaw;K. Menten;F. Nakamura;D. Seifried;K. Sugitani;H. Wiesemeyer
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文献类型：
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作者：
T. Pillai;D. Clemens;S. Reissl;P. Myers;J. Kauffmann;E. Lopez-Rodriguez;F. Alves;G. Franco;J. Henshaw;K. Menten;F. Nakamura;D. Seifried;K. Sugitani;H. Wiesemeyer
观测表明，分子云具有很强的磁化性，磁场会影响恒星的形成。支持分子云被显著磁化这一结论的一个关键观察结果是，它们内部结构的方向与磁场的方向密切相关。在低柱密度下，结构与磁场平行排列，而在较高的柱密度下，气体结构通常垂直于磁场取向，在视觉上有一个过渡。在这里，我们使用的远红外偏振观测从HAWC+偏振索菲亚报告的相对方向的进一步转变的发现，即，返回到平行排列在AV 1021等的巨蛇座南云的一部分。这种转变似乎是由气体流动引起的，表明磁超临界状态在AV = 21等附近，即使在相对较强的磁场存在下，引力坍缩和星星团的形成也会发生。
Observations indicate that molecular clouds are strongly magnetized, and that magnetic fields influence the formation of stars. A key observation supporting the conclusion that molecular clouds are significantly magnetized is that the orientation of their internal structure is closely related to that of the magnetic field. At low column densities, the structure aligns parallel with the field, whereas at higher column densities, the gas structure is typically oriented perpendicular to magnetic fields, with a transition at visual extinctionsAV≳ 3 mag. Here we use far-infrared polarimetric observations from the HAWC+ polarimeter on SOFIA to report the discovery of a further transition in relative orientation, that is, a return to parallel alignment atAV≳ 21 mag in parts of the Serpens South cloud. This transition appears to be caused by gas flow and indicates that magnetic supercriticality sets in nearAV≳ 21 mag, allowing gravitational collapse and star cluster formation to occur even in the presence of relatively strong magnetic fields.