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First Evidence of a Precessing Jet Excavating a Protostellar Envelope

Jason E. Ybarra·Mary Barsony·Karl E. Haisch, Jr.·Thomas H. Jarrett·Raghvendra Sahai·Alycia J. Weinberger
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Abstract

We present new, sensitive, near-infrared images of the Class I protostar, Elias 29, in the Ophiuchus cloud core. To explore the relationship between the infall envelope and the outflow, narrowband H2 1-0 S(1), Br-gamma, and narrowband K-continuum filters were used to image the source with the Wide-Field Infrared Camera on the Hale 5m telescope and with Persson's Auxiliary Nasmyth Infrared Camera on the Baade 6.5 m telescope. The source appears as a bipolar, scattered light nebula, with a wide opening angle in all filters, as is typical for late-stage protostars. However, the pure H2 emission-line images point to the presence of a heretofore undetected precessing jet. It is argued that high-velocity, narrow, precessing jets provide the mechanism for creating the observed wide-angled outflow cavity in this source.

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Jason E. Ybarra, Mary Barsony, Karl E. Haisch, Jr., Thomas H. Jarrett, Raghvendra Sahai, Alycia J. Weinberger. 2006-08-08. First Evidence of a Precessing Jet Excavating a Protostellar Envelope. https://doi.org/10.1086/507449

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