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arXiv · 1410.2947

Near-Infrared Circular Polarization Survey in Star-Forming Regions: Correlations and Trends

Jungmi Kwon·Motohide Tamura·James H. Hough·Nobuhiko Kusakabe·Tetsuya Nagata·Yasushi Nakajima·Phil W. Lucas·Takahiro Nagayama·Ryo Kandori
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Abstract

We have conducted a systematic near-infrared circular polarization (CP) survey in star-forming regions, covering high-mass, intermediate-mass, and low-mass young stellar objects. All the observations were made using the SIRPOL imaging polarimeter on the Infrared Survey Facility 1.4 m telescope at the South African Astronomical Observatory. We present the polarization properties of ten sub-regions in six star-forming regions. The polarization patterns, extents, and maximum degrees of linear and circular polarizations are used to determine the prevalence and origin of CP in the star-forming regions. Our results show that the CP pattern is quadrupolar in general, the CP regions are extensive, up to 0.65 pc, the CP degrees are high, up to 20 %, and the CP degrees decrease systematically from high- to low-mass young stellar objects. The results are consistent with dichroic extinction mechanisms generating the high degrees of CP in star forming regions.

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Jungmi Kwon, Motohide Tamura, James H. Hough, Nobuhiko Kusakabe, Tetsuya Nagata, Yasushi Nakajima, Phil W. Lucas, Takahiro Nagayama, Ryo Kandori. 2014-10-11. Near-Infrared Circular Polarization Survey in Star-Forming Regions: Correlations and Trends. https://doi.org/10.1088/2041-8205/795/1/l16

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