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arXiv · 0909.5227

Dispersion of Magnetic Fields in Molecular Clouds. II

Martin Houde·John E. Vaillancourt·Roger H. Hildebrand·Shadi Chitsazzadeh·Larry Kirby
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Abstract

We expand our study on the dispersion of polarization angles in molecular clouds. We show how the effect of signal integration through the thickness of the cloud as well as across the area subtended by the telescope beam inherent to dust continuum measurements can be incorporated in our analysis to correctly account for its effect on the measured angular dispersion and inferred turbulent to large-scale magnetic field strength ratio. We further show how to evaluate the turbulent magnetic field correlation scale from polarization data of sufficient spatial resolution and high enough spatial sampling rate. We apply our results to the molecular cloud OMC-1, where we find a turbulent correlation length of approximately 16 mpc, a turbulent to large-scale magnetic field strength ratio of approximately 0.5, and a plane-of-the-sky large-scale magnetic field strength of approximately 0.76 mG.

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Martin Houde, John E. Vaillancourt, Roger H. Hildebrand, Shadi Chitsazzadeh, Larry Kirby. 2009-09-28. Dispersion of Magnetic Fields in Molecular Clouds. II. https://doi.org/10.1088/0004-637x/706/2/1504

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