The Galactic Magnetic Field's Effect in Star-Forming Region

TL;DR

This study analyzes 350 micron polarization data from 52 star-forming regions to understand the influence of the Milky Way's magnetic field, revealing an ordered magnetic component at source scales but no correlation with Galactic coordinates.

Contribution

It provides the first large-scale analysis of magnetic field orientations in star-forming regions, showing their independence from the Galactic magnetic field.

Findings

Over 80% of sources have a meaningful mean magnetic field direction.

No correlation between polarization angles and Galactic coordinates.

Magnetic field directions are randomly distributed on the sky.

Abstract

We investigate the effect of the Milky Way's magnetic field in star forming regions using archived 350 micron polarization data on 52 Galactic star formation regions from the Hertz polarimeter module. The polarization angles and percentages for individual telescope beams were combined in order to produce a large-scale average for each source and for complexes of sources. In more than 80% of the sources, we find a meaningful mean magnetic field direction, implying the existence of an ordered magnetic field component at the scale of these sources. The average polarization angles were analyzed with respect to the Galactic coordinates in order to test for correlations between polarization percentage, polarization angle, intensity, and Galactic location. No correlation was found, which suggests that the magnetic field in dense molecular clouds is decoupled from the large-scale Galactic magnetic field. Finally, we show that the magnetic field directions in the complexes are consistent with a random distribution on the sky.