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BIMA and JCMT Spectropolarimetric Observations of the CO J = 2 − 1 Line Towards Orion KL/IRc2

  • J. M. Girart
  • J. S. Greaves
  • R. M. Crutcher
  • S.-P. Lai

Abstract

We present results of JCMT and BIMA CO J = 2 − 1 polarization observations towards the Orion KL/IRc2 high mass star forming region. The linear polarization fraction of the JCMT CO J = 2 − 1 spectra presents a clear decrease towards the center of the line, as expected, due to the increase of the optical depth. The position angle remains constant along the spectral line, except at the line center, where the highest optical depth and lower fractional polarization are measured. The combined BIMA and JCMT maps of the redshifted and blueshifted CO emission show a uniform polarization pattern that does not coincide with previous dust continuum observations at similar angular resolution. This suggests that the CO and dust are tracing different spatial components along the line of sight.

Keywords

polarization magnetic fields Orion KL/IRc2 

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Copyright information

© Springer Science+Business Media Dordrecht 2004

Authors and Affiliations

  • J. M. Girart
    • 1
  • J. S. Greaves
    • 2
  • R. M. Crutcher
    • 3
  • S.-P. Lai
    • 4
  1. 1.Departament d’Astronomia i MeteorologiaUniversitat de BarcelonaBarcelona, CatalunyaSpain
  2. 2.Royal ObservatoryEdinburghScotland, UK
  3. 3.Astronomy DepartmentUniversity of IllinoisUrbanaUSA
  4. 4.Jet Propulsion LabCalifornia Institute of TechnologyPasadenaUSA

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