MULTIPLICITY, DISKS, AND JETS IN THE NGC 2071 STAR-FORMING REGION

• Published in: The Astrophysical journal Vol. 746; no. 1; pp. 1 - 10
• Main Authors: CARRASCO-GONZALEZ, Carlos, OSORIO, Mayra, ANGLADA, Gutllem, D'ALESSIO, Paola, RODRIGUEZ, Luis F, GOMEZ, José F, TORRELLES, José M
• Format: Journal Article
• Language: English
• Published: Bristol IOP 10.02.2012
• Subjects: ACCRETION DISKS; Arrays; ASTRONOMY; ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; Disks; DUSTS; Earth, ocean, space; Emission; ENERGY SPECTRA; Exact sciences and technology; Jets; MASS; MORPHOLOGY; PROTOPLANETS; Spectral energy distribution; Star formation; STARS; Wavelengths; ISM: jets and outflows; Intensity; Stellar formation region; Spectral energy distribution; Young stellar object; radio continuum: ISM; Accretion disks; Proto planetary nebula; Continuum; stars: formation; Star formation; ISM: individual objects (NGC 2071); Morphology; Multiplicity; Jets; Models; Circumstellar disks; protoplanetary disks
• ISSN: 0004-637X; 1538-4357
• DOI: 10.1088/0004-637X/746/1/71

We present centimeter (cm) and millimeter (mm) observations of the NGC 2071 star-forming region performed with the Very Large Array (VLA) and Combined Array for Research in Millimeter-wave Astronomy (CARMA). We detected counterparts at 3.6 cm and 3 mm for the previously known sources IRS 1, IRS 2, IRS 3, and VLA 1. All these sources show spectral energy distributions (SEDs) dominated by free-free thermal emission at cm wavelengths and thermal dust emission at mm wavelengths, suggesting that all of them are associated with young stellar objects (YSOs). IRS 1 shows a complex morphology at 3.6 cm, with changes in the direction of its elongation. We discuss two possible explanations to this morphology: the result of changes in the direction of a jet due to interactions with a dense ambient medium, or that we are actually observing the superposition of two jets arising from two components of a binary system. Higher angular resolution observations at 1.3 cm support the second possibility, since a double source is inferred at this wavelength. IRS 3 shows a clear jet-like morphology at 3.6 cm. Over a timespan of four years, we observed changes in the morphology of this source that we interpret as due to ejection of ionized material in a jet. The emission at 3 mm of IRS 3 is angularly resolved, with a deconvolved size (FWHM) of ~120 AU, and seems to be tracing a dusty circumstellar disk perpendicular to the radio jet. An irradiated accretion disk model around an intermediate-mass YSO can account for the observed SED and spatial intensity profile at 3 mm, supporting this interpretation.