Spectropolarimetric Clues to the Structure
and Evolutionary Status of MWC 349A
Jill M. Meyer1,2,
Kenneth H. Nordsieck1,
and
Jennifer L. Hoffman1
1
Department of Astronomy, University of Wisconsin-Madison, 475
N. Charter St., Madison, WI 53706
2
Maria Mitchell Observatory, 3 Vestal St., Nantucket, MA 02554
We present visible-wavelength spectropolarimetric measurements of the
emission-line star MWC 349A and its close optical companion MWC 349B,
conducted with the HPOL spectropolarimeter on both the 0.9 m telescope
at the University of Wisconsin's Pine Bluff Observatory and the 3.5 m
WIYN telescope on Kitt Peak. Our measurements allow us to estimate the
interstellar polarization contribution and thus constrain the
intrinsic polarization of MWC 349A, which we find to be consistent in
position angle with the dusty disk seen perpendicular to the bipolar
outflow. Our analysis reopens the possibility that MWC 349A may be
part of the Cyg OB2 association, suggests that it is not a physical
companion to MWC 349B, and supports the classification of MWC 349A as
a pre-main sequence B[e] star.
Accepted by AJ
Preprints from
jhoffman@sal.wisc.edu
or on the web at
http://xxx.lanl.gov/abs/astro-ph/0112285
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