Intrinsically polarized stars and implication for star formation in the central parsec of our galaxy

Journal Article · Sun Dec 01 04:00:00 EST 2013 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/778/2/92· OSTI ID:22341978

Yoshikawa, Tatsuhito; Nagata, Tetsuya ^[1]; Nishiyama, Shogo; Tamura, Motohide ^[2]; Ishii, Miki ^[3]

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1. Department of Astronomy, Graduate School of Science, Kyoto University, Kyoto 606-8502 (Japan)
2. National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan)
3. Subaru Telescope, National Astronomical Observatory of Japan, 650 North A'ohoku Place, Hilo, HI 96720 (United States)

We have carried out adaptive-optics assisted observations at the Subaru Telescope and have found 11 intrinsically polarized sources in the central parsec of our Galaxy. They are selected from 318 point sources with K{sub S} < 15.5, and their interstellar polarizations are corrected using a Stokes Q/I-U/I diagram. Considering brightness, near-infrared color excess, and the amount of intrinsic polarization, two of them are good young stellar object (YSO) candidates with an age of ∼10{sup 5} yr. If they are genuine YSOs, their existence provides strong constraints on star formation mechanisms in this region. In the remaining sources, two are known as bow-shock sources in the Northern Arm. One other is also located in the Northern Arm and shows very similar properties, and thus it is likely to be a so far unknown bow-shock source. The origin of the intrinsic polarization of the other sources is as yet uncertain.

• OSTI ID: 22341978
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 778; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
BRIGHTNESS
COLOR
GALAXIES
LIMITING VALUES
POINT SOURCES
POLARIZATION
SHOCK WAVES
STARS
TELESCOPES