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→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→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.
@article{arxiv.0801.4316,
title = {Interferometric Mapping of Magnetic Fields: The massive star forming region G34.4+0.23 MM},
author = {P. C. Cortes and R. M. Crutcher and D. Shepherd and L. Bronfman},
journal= {arXiv preprint arXiv:0801.4316},
year = {2009}
}