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arXiv · 1009.0584

Magnetic Field Configuration at the Galactic Center Investigated by Wide Field Near-Infrared Polarimetry: Transition from a Toroidal to a Poloidal Magnetic Field

Shogo Nishiyama·Hirofumi Hatano·Motohide Tamura·Noriyuki Matsunaga·Tatsuhito Yoshikawa·Takuya Suenaga·James H. Hough·Koji Sugitani·Takahiro Nagayama·Daisuke Kato·Tetsuya Nagata
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Abstract

We present a large-scale view of the magnetic field in the central 2deg * 2deg region of our Galaxy. The polarization of point sources has been measured in the J, H, and Ks bands using the near-infrared polarimetric camera SIRPOL on the 1.4 m telescope IRSF. Comparing the Stokes parameters between high extinction stars and relatively low extinction ones, we obtain polarization originating from magnetically aligned dust grains in the central few-hundred pc of our Galaxy. We find that near the Galactic plane, the magnetic field is almost parallel to the Galactic plane (i.e., toroidal configuration) but at high Galactic latitudes (| b | > 0.4deg), the field is nearly perpendicular to the plane (i.e., poloidal configuration). This is the first detection of a smooth transition of the large-scale magnetic field configuration in this region.

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Shogo Nishiyama, Hirofumi Hatano, Motohide Tamura, Noriyuki Matsunaga, Tatsuhito Yoshikawa, Takuya Suenaga, James H. Hough, Koji Sugitani, Takahiro Nagayama, Daisuke Kato, Tetsuya Nagata. 2010-09-03. Magnetic Field Configuration at the Galactic Center Investigated by Wide Field Near-Infrared Polarimetry: Transition from a Toroidal to a Poloidal Magnetic Field. https://doi.org/10.1088/2041-8205%2F722%2F1%2Fl23

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