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Near-Infrared Imaging Polarimetry of the NGC 2071 Star Forming Region with SIRPOL

Motohide Tamura·Ryo Kandori·Jun Hashimoto·Nobuhiko Kusakabe·Yasushi Nakajima·Shuji Ssato·Chie Nagashima·Mikio Kurita·Tetsuya Nagata·Takahiro Nagayama·Jim Hough·Tomoaki Matsumoto·Antonio Chrysostomou
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Abstract

We have conducted deep JHKs imaging polarimetry of a ~8' x 8' area of the NGC 2071 star forming region. Our polarization data have revealed various infrared reflection nebulae (IRNe) associated with the central IR young star cluster NGC2071IR and identified their illuminating sources. There are at least 4 IRNe in NGC2071IR and several additional IRNe are identified around nearby young stars in the same field-of-view. Each illuminating source coincides with a known near-IR source except for IRS3, which is only a part of IRN2 and is illuminated by the radio source 1c. Aperture polarimetry of each cluster source is used to detect unresolved circumstellar disk/outflow systems. Aperture polarimetry of the other point-like sources within the field is made in this region for the first time. The magnetic field structures (from ~1 pc down to \~0.1 pc) are derived using both aperture polarimetry of the point-like sources and imaging polarimetry of the shocked H2 emission that is seen as the dominant knotty nebulae in the Ks band image; they are both of dichroic origin and the derived field directions are consistent with each other. The magnetic field direction projected on the sky is also consistent with that inferred from the 850 micron thermal continuum emission polarimetry of the central 0.2 pc region, but running roughly perpendicular (~75 degrees) to the direction of the large scale outflow. We argue that the field strength is too weak to align the outflow in the large scale field direction via magnetic braking.

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Motohide Tamura, Ryo Kandori, Jun Hashimoto, Nobuhiko Kusakabe, Yasushi Nakajima, Shuji Ssato, Chie Nagashima, Mikio Kurita, Tetsuya Nagata, Takahiro Nagayama, Jim Hough, Tomoaki Matsumoto, Antonio Chrysostomou. 2007-01-19. Near-Infrared Imaging Polarimetry of the NGC 2071 Star Forming Region with SIRPOL. https://doi.org/10.1093/pasj%2F59.3.467

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