Magnetic fields in star-forming molecular clouds. I. The first polarimetry of OMC-3 in Orion A

The first polarimetric images of the OMC-3 region of the Orion A filamentary molecular cloud are presented. Using the new imaging polarimeter on the Submillimeter Common User Bolometric Array at the James Clerk Maxwell Telescope, we have detected polarized thermal emission at 850 μm from dust along a 6′ length of the dense filament. The polarization pattern is highly ordered and is aligned with the long axis of the filament throughout most of …