To appear in the Astrophysical Journal Letters NEAR-INFRARED CIRCULAR POLARIZATION SURVEY IN STAR-FORMING REGIONS: CORRELATIONS AND TRENDS
نویسندگان
چکیده
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 highto low-mass young stellar objects. The results are consistent with dichroic extinction mechanisms generating the high degrees of CP in star forming regions. Subject headings: dust, extinction — infrared: ISM — ISM: magnetic fields — polarization — stars: formation — surveys
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تاریخ انتشار 2014