Silicon monoxide and methanol emission from the NGC 2071 molecular outflow
Author
dc.contributor.author
Garay Brignardello, Guido
Author
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Mardones Pérez, Diego
es_CL
Author
dc.contributor.author
Rodríguez, L. F.
Admission date
dc.date.accessioned
2014-01-06T19:12:34Z
Available date
dc.date.available
2014-01-06T19:12:34Z
Publication date
dc.date.issued
2000-12-20
Cita de ítem
dc.identifier.citation
THE ASTROPHYSICAL JOURNAL, 545:861È873, 2000 December 20
en_US
Identifier
dc.identifier.uri
https://repositorio.uchile.cl/handle/2250/125968
General note
dc.description
Artículo de publicación ISI
en_US
Abstract
dc.description.abstract
We report observations of emission in the J\3]2 and J\2]1 transitions of SiO and Jk\
3k transitions of made with the Swedish-ESO Submillimeter Telescope (SEST), toward the
]2k CH3OH,
high-velocity, collimated molecular outÑow in NGC 2071. Emission is detected from the lobes, as well as
from the central core region, in both species. The spatial distribution of the SiO wing emission, which is
detected over a velocity range of D50 km s~1, shows three distinct features : a blueshifted clump located
toward the northeast, a redshifted clump located toward the southwest, and a central structure, with
moderate redshifted velocities, located near the cluster of young stellar objects. The shape of the SiO
proÐles from the northeast and southwest clumps are distinctly di erent. The SiO lines from the northeast
clump exhibit a peak near the velocity of the ambient cloud and a gradual decline toward blueshifted
velocities reaching Ñow velocities of up to [32 km s~1. On the other hand, the SiO proÐles from
the southwest clump show a peak emission at a velocity that is redshifted by D8.5 km s~1 from the
ambient gas velocity and a gradual decline in brightness toward the ambient cloud velocity. We suggest
that the SiO emission from the clumps are signposts of working surfaces where a collimated jet is interacting
with ambient material, and ascribe the di erences in line shape to di erences in the density of the
environment under which the jet is propagating.
The abundance of silicon monoxide in the outÑow lobes is found to be enhanced, with respect to that
of quiescent ambient gas in dark globules, by at least 2 orders of magnitude (peak enhancement º500 in
the southwest clump and º170 in the northeast clump). The abundance of methanol is considerably
more enhanced in the southwest clump (peak enhancement of D500) than in the northwest clump (peak
enhancement of D70). We suggest that the large enhancements of methanol and silicon monoxide in the
outÑow clumps are most likely due to the release from grains of ice mantles and Si-bearing species via
shocks produced by the interaction between the outÑow and dense ambient gas, and attribute the di erences
in enhancements to the di erent shock velocities attained in the northeast clump (vsD45 km s~1)
and southwest clump (vsD12 km s~1).