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arXiv · 1108.1342

Detection of a Bipolar Molecular Outflow Driven by a Candidate First Hydrostatic Core

Michael M. Dunham·Xuepeng Chen·Hector G. Arce·Tyler L. Bourke·Scott Schnee·Melissa L. Enoch
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Abstract

We present new 230 GHz Submillimeter Array observations of the candidate first hydrostatic core Per-Bolo 58. We report the detection of a 1.3 mm continuum source and a bipolar molecular outflow, both centered on the position of the candidate first hydrostatic core. The continuum detection has a total flux density of 26.6 +/- 4.0 mJy, from which we calculate a total (gas and dust) mass of 0.11 +/- 0.05 Msun and a mean number density of 2.0 +/- 1.6 X 10^7 cm-3. There is some evidence for the existence of an unresolved component in the continuum detection, but longer-baseline observations are required in order to confirm the presence of this component and determine whether its origin lies in a circumstellar disk or in the dense inner envelope. The bipolar molecular outflow is observed along a nearly due east-west axis. The outflow is slow (characteristic velocity of 2.9 km/s), shows a jet-like morphology (opening semi-angles ~8 degrees for both lobes), and extends to the edges of the primary beam. We calculate the kinematic and dynamic properties of the outflow in the standard manner and compare them to several other protostars and candidate first hydrostatic cores with similarly low luminosities. We discuss the evidence both in support of and against the possibility that Per-Bolo 58 is a first hydrostatic core, and we outline future work needed to further evaluate the evolutionary status of this object.

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Michael M. Dunham, Xuepeng Chen, Hector G. Arce, Tyler L. Bourke, Scott Schnee, Melissa L. Enoch. 2011-08-05. Detection of a Bipolar Molecular Outflow Driven by a Candidate First Hydrostatic Core. https://doi.org/10.1088/0004-637x/742/1/1

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