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arXiv · 1908.00689

An Episodic Wide-angle Outflow in HH 46/47

Yichen Zhang·Hector G. Arce·Diego Mardones·Sylvie Cabrit·Michael M. Dunham·Guido Garay·Alberto Noriega-Crespo·Stella S. R. Offner·Alejandro C. Raga·Stuartt A. Corder
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Abstract

During star formation, the accretion disk drives fast MHD winds which usually contain two components, a collimated jet and a radially distributed wide-angle wind. These winds entrain the surrounding ambient gas producing molecular outflows. We report recent observation of 12CO (2-1) emission of the HH 46/47 molecular outflow by the Atacama Large Millimeter/sub-millimeter Array, in which we identify multiple wide-angle outflowing shell structures in both the blue and red-shifted outflow lobes. These shells are highly coherent in position-position-velocity space, extending to >40-50 km/s in velocity and 10^4 au in space with well defined morphology and kinematics. We suggest these outflowing shells are the result of the entrainment of ambient gas by a series of outbursts from an intermittent wide-angle wind. Episodic outbursts in collimated jets are commonly observed, yet detection of a similar behavior in wide-angle winds has been elusive. Here we show clear evidence that the wide-angle component of the HH 46/47 protostellar outflows experiences similar variability seen in the collimated component.

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Yichen Zhang, Hector G. Arce, Diego Mardones, Sylvie Cabrit, Michael M. Dunham, Guido Garay, Alberto Noriega-Crespo, Stella S. R. Offner, Alejandro C. Raga, Stuartt A. Corder. 2019-08-02. An Episodic Wide-angle Outflow in HH 46/47. https://doi.org/10.3847/1538-4357/ab3850

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