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