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arXiv · 1310.3142

Intrinsically Polarized Stars and Implication for Star Formation in the Central Parsec of Our Galaxy

Tatsuhito Yoshikawa·Shogo Nishiyama·Motohide Tamura·Miki Ishii·Tetsuya Nagata
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Abstract

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 Ks<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 ~10^5 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 likely to be a so far unknown bow-shock source. The origin of the intrinsic polarization of the other sources is as yet uncertain.

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Tatsuhito Yoshikawa, Shogo Nishiyama, Motohide Tamura, Miki Ishii, Tetsuya Nagata. 2013-10-11. Intrinsically Polarized Stars and Implication for Star Formation in the Central Parsec of Our Galaxy. https://doi.org/10.1088/0004-637x/778/2/92

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