The Link between Magnetic-field Orientations and Star Formation Rates

TL;DR

This study reveals a correlation between magnetic-field orientations and star formation rates, showing that clouds perpendicular to magnetic fields tend to have lower SFR due to magnetic support against gravity.

Contribution

It provides the first observational evidence linking magnetic-field alignment with star formation efficiency, highlighting magnetic fields as a key regulator.

Findings

Perpendicular magnetic-field alignment correlates with lower SFR.

Perpendicular alignment has higher magnetic flux, supporting gas against gravity.

Lower masses of fragmented components are associated with perpendicular alignment.

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.