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arXiv · 1706.08452

The Link between Magnetic-field Orientations and Star Formation Rates

Hua-bai Li·Hangjin Jiang·Xiaodan Fan·Qilao Gu·Yapeng Zhang
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Abstract

Understanding star formation rates (SFR) is a central goal of modern star-formation models, which mainly involve gravity, turbulence and, in some cases, magnetic fields (B-fields). However, a connection between B-fields and SFR has never been observed. Here, a comparison between the surveys of SFR and a study of cloud-field alignment - which revealed a bimodal (parallel or perpendicular) alignment - shows consistently lower SFR per solar mass for clouds almost perpendicular to the B-fields. This is evidence of B-fields being a primary regulator of SFR. The perpendicular alignment possesses a significantly higher magnetic flux than the parallel alignment and thus a stronger support of the gas against self-gravity. This results in overall lower masses of the fragmented components, which are in agreement with the lower SFR.

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Hua-bai Li, Hangjin Jiang, Xiaodan Fan, Qilao Gu, Yapeng Zhang. 2017-06-26. The Link between Magnetic-field Orientations and Star Formation Rates. https://doi.org/10.1038/s41550-017-0158

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