Mapping Magnetic Fields in the Cold Dust at the Galactic Center

David T. Chuss,1 Giles Novak,2 Roger H. Hildebrand,3 John E. Vaillancourt,4 C. Darren Dowell,5 Jessie L. Dotson,6 Jacqueline A. Davidson6

1 NASA Goddard Space Flight Center
2 Northwestern University
3 Enrico Fermi Institute, University of Chicago
4 University of Wisconsin
5 California Institute of Technology
6 NASA Ames Research Center

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We report the measurement of 158 new 350 m polarimetry vectors in the central 30 parsecs of the Galactic center. These data were obtained at the Caltech Submillimeter Observatory using Hertz. Morphologically, these results show a consistency with previously published far-infrared and submillimeter results. We find that the angle of the magnetic field inferred from these observations is related to the 350 microns flux as obtained by SHARC in the following way. At low fluxes, the magnetic field angle is consistent with that of a poloidal field as seen in nearby features such as the Galactic Center Radio Arc and the Northern and Southern Threads. At high fluxes, the magnetic field is oriented parallel to the plane of the Galaxy. This relationship suggests a model in which an initially poloidal field is sheared out in dense regions which are dominated by gravity. If this model is correct, it implies a characteristic field strength for the region of 5 mG.