C. Carrasco-Gonzalez, M. Osorio, G. Anglada, P. D'Alessio, L. F. Rodriguez, J. F. Gomez, J. M. Torrelles
We present centimeter and millimeter observations of the NGC 2071
star-forming region performed with the VLA and 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 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 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 time-span 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.
View original:
http://arxiv.org/abs/1111.5469
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