Mid-infrared spectropolarimetry of MWC 349 : a hydromagnetically driven outflow ?
Abstract
We present 8-l3-μm spectropolarimetry of the Bep star MWC 349A. The intensity spectrum indicates significantly more obscuration to the infrared source than to the visible object. A polarization peak of 1.5 per cent near 11 μm is interpreted as dichroic absorption by aligned silicate grains which probably lie in the dense disc which has been partially resolved in the near infrared. The position angle of polarization indicates a magnetic field, normal to the plane of this disc and aligned with the bipolar radio structure. We suggest that this magnetic field plays a role in the outflow through magnetic braking of the rotation of the central star.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- December 1990
- Bibcode:
- 1990MNRAS.247..466A