Near-Infrared Polarimetry toward the Galactic Center
نویسندگان
چکیده
Near-infrared polarimetry of point sources reveals the presence of a toroidal magnetic field in the central 20’ x 20’ region of our Galaxy. Comparing the Stokes parameters between high extinction stars and relatively low extinction ones, we have obtained a polarization originating from magnetically aligned dust grains at the central region of our Galaxy of at most 1-2 kpc. The derived direction of the magnetic field is in good agreement with that obtained from farinfrared/submillimeter observations, which detect polarized thermal emission from dust in the molecular clouds at the Galactic center. Our results show that by subtracting foreground components, near-infrared polarimetry allows investigation of the magnetic field structure at the Galactic center. The distribution of the position angles shows a peak at around 20, nearly parallel to the direction of the Galactic plane, suggesting a toroidal magnetic configuration.
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