原恒星HOPS 10的单极喷流：对非对称磁化喷射的证据
A Monopolar Jet from Protostar HOPS 10: Evidence for Asymmetric Magnetized Launching
AI总结：
原恒星HOPS 10的单极喷流揭示了非对称磁化喷射的证据，通过高分辨率观测确认了高速喷流的单极性，暗示盘磁力线上的非对称质量加载可能是原因。
摘要：
恒星形成中的一个基本挑战是理解原恒星如何从其周围星周盘中吸积质量，同时去除多余的角动量。原恒星喷流被广泛认为是角动量去除的主要通道，但它们是如何被发射并提取角动量的机制仍不明确。在这里，我们报告了使用ALMA带7（345 GHz）和带6（230 GHz）的高分辨率观测，观测了原恒星HOPS 10（G209.55-19.68S2）的CO（3-2）、CO（2-1）和SiO（5-4）发射。结合的数据追踪了被卷入的出流和受约束的喷流，具有出色的时空和速度分辨率，揭示了独一无二的单极原恒星喷流，迄今为止最清晰的例子。该系统表现出明显单极的高速喷流，速度偏移为+44至+66 km s-1，不同于大多数原恒星喷流以双极形态为特征。虽然低速出流，速度偏移为-20至+30 km s-1，在两个方向上均被检测到，但高速喷流只出现在一侧，这种单极性在所有示踪剂中都是一致的。鉴于几乎边缘视几何和低亚毫米波消光，通常预期从两个lobes会有相当的发射。SiO发射的激波示踪剂确认了真实的、高度受约束的喷流，而不是云污染，并且没有周围的结构能够遮蔽反喷流。我们认为，沿盘磁力线的非对称质量加载提供了观察到单极性的最可能解释。
英文摘要：
A fundamental challenge in star formation is understanding how a protostar accretes mass from its circumstellar disk while removing excess angular momentum. Protostellar jets are widely invoked as the primary channels for angular momentum removal, yet the mechanism by which they are launched and extract angular momentum remains poorly constrained. Here we report high-resolution ALMA Band 7 (345 GHz) and Band 6 (230 GHz) observations of CO (3-2), CO (2-1), and SiO (5-4) emission from the protostar HOPS 10 (G209.55-19.68S2). The combined data trace both the entrained outflow and the collimated jet with excellent spatial and velocity resolution, revealing a uniquely monopolar protostellar jet, the clearest example reported to date. The system exhibits a distinctly unipolar high-velocity jet with velocity offsets of +44 to +66 km s-1, unlike the predominantly bipolar morphology characteristic of most protostellar jets. While the low-velocity outflow, with velocity offsets of -20 to +30 km s-1, is detected in both directions, the high-velocity jet appears only on one side, and this monopolarity is consistent across all tracers. Given the nearly edge-on geometry and low submillimeter extinction, comparable emission would normally be expected from both lobes. The shock tracer SiO emission confirms a genuine, highly collimated jet rather than cloud contamination, and no ambient structure is capable of obscuring a counterjet. We argue that intrinsically asymmetric mass loading along the disk magnetic field lines provides the most plausible explanation for the observed monopolarity.
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。
