MAGNETIC FIELD CONFIGURATION AT THE GALACTIC CENTER INVESTIGATED BY WIDE-FIELD NEAR-INFRARED POLARIMETRY: TRANSITION FROM A TOROIDAL TO A POLOIDAL MAGNETIC FIELD

Journal Article · Sun Oct 10 04:00:00 EDT 2010 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/722/1/L23· OSTI ID:21452769

Nishiyama, Shogo; Yoshikawa, Tatsuhito; Nagata, Tetsuya ^[1]; Hatano, Hirofumi; Nagayama, Takahiro ^[2]; Tamura, Motohide ^[3]; Matsunaga, Noriyuki ^[4]; Suenaga, Takuya ^[5]; Hough, James H ^[6]; Sugitani, Koji ^[7]; Kato, Daisuke ^[8]

---

1. Department of Astronomy, Kyoto University, Kitashirakawa-oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan)
2. Department of Astrophysics, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan)
3. National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
4. Kiso Observatory, Institute of Astronomy, University of Tokyo, 10762-30 Mitake, Kiso, Nagano 397-0101 (Japan)
5. Department of Astronomical Sciences, Graduate University for Advanced Studies (Sokendai), 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan)
6. Centre for Astrophysics Research, Science and Technology Research Institute, University of Hertfordshire, Hatfield AL10 9AB (United Kingdom)
7. Graduate School of Natural Sciences, Nagoya City University, 1 Yamanohata, Mizuho-cho, Mizuho-ku, Nagoya 467-8501 (Japan)
8. Institute of Space and Astronomical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo-ku, Sagamihara, Kanagawa, 252-5210 (Japan)

We present a large-scale view of the magnetic field (MF) in the central 2{sup 0} x 2{sup 0} region of our Galaxy. The polarization of point sources has been measured in the J, H, and K{sub S} bands using the near-infrared polarimetric camera SIRPOL on the 1.4 m Infrared Survey Facility telescope. 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 parsecs of our Galaxy. We find that near the Galactic plane, the MF is almost parallel to the Galactic plane (i.e., toroidal configuration), but at high Galactic latitudes (|b | >0.{sup 0}4) 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 MF configuration in this region.

• OSTI ID: 21452769
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 1 Vol. 722; ISSN 2041-8205
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ANNULAR SPACE
CLOSED CONFIGURATIONS
CONFIGURATION
DUSTS
GALAXIES
GEOLOGIC SURVEYS
GEOPHYSICAL SURVEYS
INFRARED SURVEYS
MAGNETIC FIELD CONFIGURATIONS
MAGNETIC FIELDS
POINT SOURCES
POLARIMETRY
RADIATION SOURCES
SPACE
STARS
STOKES PARAMETERS
TELESCOPES
TOROIDAL CONFIGURATION