Infrared polarimetry of the southern massive star-forming region G333.6-0.2

Citation
T. Fujiyoshi et al., Infrared polarimetry of the southern massive star-forming region G333.6-0.2, M NOT R AST, 327(1), 2001, pp. 233-243
Citations number
45
Categorie Soggetti
Space Sciences
Journal title
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
ISSN journal
00358711 → ACNP
Volume
327
Issue
1
Year of publication
2001
Pages
233 - 243
Database
ISI
SICI code
0035-8711(20011011)327:1<233:IPOTSM>2.0.ZU;2-A
Abstract
We present 8-13 mum spectropolarimetry, and 12- and 2-mum imaging polarimet ry of the southern massive star-forming region G333.6-0.2. Spectropolarimet ry measurements show that the polarization observed towards the nebula cont ains a mixture of both absorptive and emissive polarizations. Model fitting to the spectra indicates that the temperature of the mid-infrared emitting dust grains is generally similar to 200 K and the optical depth of the abs orbing dust at 9.7 mum is similar to1.5. Fits are also made to the polarime try spectra, which show a reasonably constant peak absorptive polarization (similar to3.4 per cent at 43 degrees) across the face of the H II region. This absorptive polarization position angle is consistent with that found b y the 2-mum imaging polarimetry (38 degrees +/- 6 degrees) and is most like ly due to the Galactic magnetic field local to G333.6-0.2. When the absorpt ive polarization is subtracted from the 12-mum polarization image, the emis sive polarization pattern that is intrinsic to the star-forming region is r evealed. A probable magnetic field configuration implied by the intrinsic p olarization suggests star formation initially influenced by the Galactic ma gnetic field which is eventually perturbed by the star formation process.