Magnetic field structure in the Flattened Envelope and Jet in the young protostellar system HH 211

TL;DR

This study maps magnetic fields in the young protostellar system HH 211, revealing complex polarization patterns in the envelope and potential polarized SiO emission in the jet, advancing understanding of magnetic influence in star formation.

Contribution

First detection of polarized SiO line emission in a protostellar jet and detailed mapping of magnetic fields in the envelope of HH 211.

Findings

Magnetic field lines in the envelope show varied orientations consistent with collapse models.

Possible first detection of polarized SiO emission in a protostellar jet.

Magnetic field morphology in the jet remains to be clarified with higher sensitivity observations.

Abstract

HH 211 is a young Class 0 protostellar system, with a flattened envelope, a possible rotating disk, and a collimated jet. We have mapped it with the Submillimeter Array in 341.6 GHz continuum and SiO J=8-7 at ~ 0.6 resolution. The continuum traces the thermal dust emission in the flattened envelope and the possible disk. Linear polarization is detected in the continuum in the flattened envelope. The field lines implied from the polarization have different orientations, but they are not incompatible with current gravitational collapse models, which predict different orientation depending on the region/distance. Also, we might have detected for the first time polarized SiO line emission in the jet due to the Goldreich-Kylafis effect. Observations at higher sensitivity are needed to determine the field morphology in the jet.