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arXiv · 0710.2314

A Flattened Protostellar Envelope in Absorption around L1157

Leslie Looney·John Tobin·Woojin Kwon
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Abstract

Deep Spitzer IRAC images of L1157 reveal many of the details of the outflow and the circumstellar environment of this Class 0 protostar. In IRAC band 4, 8 microns, there is a flattened structure seen in absorption against the background emission. The structure is perpendicular to the outflow and is extended to a diameter of 2 arcminutes. This structure is the first clear detection of a flattened circumstellar envelope or pseudo-disk around a Class 0 protostar. Such a flattened morphology is an expected outcome for many collapse theories that include magnetic fields or rotation. We construct an extinction model for a power-law density profile, but we do not constrain the density power-law index.

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Leslie Looney, John Tobin, Woojin Kwon. 2007-10-11. A Flattened Protostellar Envelope in Absorption around L1157. https://doi.org/10.1086/524361

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