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arXiv · 0801.4316

Interferometric Mapping of Magnetic Fields: The massive star forming region G34.4+0.23 MM

P. C. Cortes·R. M. Crutcher·D. Shepherd·L. Bronfman
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Abstract

We report millimeter interferometric observations of polarized continuum and line emission from the massive star forming region G34.4. Polarized thermal dust emission at 3 mm wavelength and CO $J=1 \to 0$ line emission were observed using the Berkeley-Illinois-Maryland Association (BIMA) array. Our results show a remarkably uniform polarization pattern in both dust and in CO J=$1 \to 0$ emission. In addition, the line emission presents a consistent uniform polarization pattern over most of the velocity channel maps. These uniform polarization patterns are aligned with the north-south main axis of the filament between the main millimeter source (MM) and the ultra-compact H {\scriptsize II} region, which are the central sources in G34.4, suggesting a magnetic field orthogonal to this axis. This morphology is consistent with a magnetically supported disk seen roughly edge-on.

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P. C. Cortes, R. M. Crutcher, D. Shepherd, L. Bronfman. 2008-01-28. Interferometric Mapping of Magnetic Fields: The massive star forming region G34.4+0.23 MM. https://doi.org/10.1086/524355

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