Chuss, “Results of SPARO 2003: Mapping magnetic fields in giant molecular clouds,” ApJ 648

We present results from the Austral Winter 2003 observing campaign of SPARO, a 450 µm polarimeter used with a two-meter telescope at South Pole. We mapped large-scale magnetic fields in four Giant Molecular Clouds (GMCs) in the Galactic disk: NGC 6334, the Carina Nebula, G333.6-0.2 and G331.5-0.1. W...

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Bibliographic Details
Main Authors: H. Li, G. S. Griffin, M. Krejny, G. Novak, R. F. Loewenstein, M. G. Newcomb, P. G. Calisse, D. T. Chuss
Other Authors: The Pennsylvania State University CiteSeerX Archives
Format: Text
Language:English
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Online Access:http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.339.1091
http://arxiv.org/pdf/astro-ph/0602455v1.pdf
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Summary:We present results from the Austral Winter 2003 observing campaign of SPARO, a 450 µm polarimeter used with a two-meter telescope at South Pole. We mapped large-scale magnetic fields in four Giant Molecular Clouds (GMCs) in the Galactic disk: NGC 6334, the Carina Nebula, G333.6-0.2 and G331.5-0.1. We find a statistically significant correlation of the inferred field directions with the orientation of the Galactic plane. Specifically, three of the four GMCs (NGC 6334 is the exception) have mean field directions that are within 15 ◦ of the plane. The simplest interpretation is that the field direction tends to be preserved during the process of GMC formation. We have also carried out an analysis of published optical polarimetry data. For the closest of the SPARO GMCs, NGC 6334, we can compare the field direction in the cloud as measured by SPARO with the field direction in a larger region (several hundred pc) surrounding the cloud, as determined from optical polarimetry. For purposes of comparison, we also use optical polarimetry to determine field directions for 9-10 other regions of similar