Distortion of Magnetic Fields in a Starless Core. III. Polarization–Extinction Relationship in FeSt 1-457

• 長田, 哲也

  Department of Astronomy, The University of Tokyo

• Tamura, Motohide

  Department of Astronomy, The University of Tokyo･National Astronomical Observatory of Japan･Astrobiology Center of NINS

• Nagata, Tetsuya

  Kyoto University

• Tomisaka, Kohji

  National Astronomical Observatory of Japan

• Kusakabe, Nobuhiko

  Astrobiology Center of NINS

• Nakajima, Yasushi

  Hitotsubashi University

• Kwon, Jungmi

  Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency

• Nagayama, Takahiro

  Kagoshima University

• Tatematsu, Ken’ichi

  National Astronomical Observatory of Japan

抄録

The relationship between dust polarization and extinction was determined for the cold dense starless molecular cloud core FeSt 1-457 based on the background star polarimetry of dichroic extinction at near-infrared wavelengths. Owing to the known (three-dimensional) magnetic field structure, the observed polarizations from the core were corrected by considering (a) the subtraction of the ambient polarization component, (b) the depolarization effect of inclined distorted magnetic fields, and (c) the magnetic inclination angle of the core. After these corrections, a linear relationship between polarization and extinction was obtained for the core in the range up to A v ≈ 20 mag. The initial polarization versus extinction diagram changed dramatically after the corrections of (a) to (c), with the correlation coefficient being refined from 0.71 to 0.79. These corrections should affect the theoretical interpretation of the observational data. The slope of the finally obtained polarization–extinction relationship is PH/EH - Ks = 11.00 ± 0.72 % mag⁻¹, which is close to the statistically estimated upper limit of the interstellar polarization efficiency. This consistency suggests that the upper limit of interstellar polarization efficiency might be determined by the observational viewing angle toward polarized astronomical objects.

収録刊行物

• The Astrophysical Journal

  The Astrophysical Journal 857 100-, 2018-04-20

  American Astronomical Society

キーワード

• dust, extinction
• ISM: clouds
• polarization
• stars: formation

詳細情報

• CRID: 1050283687642128768
• NII論文ID: 120006782244
• ISSN: 15384357
• ISSN: 0004637X
• DOI: 10.3847/1538-4357/aab962
• HANDLE: 2433/245551
• Web Site: http://stacks.iop.org/0004-637X/857/i=2/a=100/pdf
• Web Site: http://stacks.iop.org/0004-637X/857/i=2/a=100?key=crossref.b770f8e9f446441d8f071a10c8928e8c
• Web Site: https://iopscience.iop.org/article/10.3847/1538-4357/aab962
• Web Site: https://iopscience.iop.org/article/10.3847/1538-4357/aab962/pdf
• 本文言語コード: en
• 資料種別: journal article
• データソース種別:
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