G. Manjarrez, J. F. Gomez, I. de Gregorio-Monsalvo
We present Very Large Array (VLA) high resolution observations of the
NH3(1,1) and NH3(2,2) molecular transitions towards the high mass star forming
region AFGL 437. Our aim was to investigate if the poorly collimated CO
molecular outflow previously detected in the region is the result of a
projection effect, with no intrinsic bipolarity, as suggested by Gomez et al.
We complemented our observations with radio continuum archived data from the
VLA at 2 and 3.6 cm, and with unpublished public data at 450 {\mu}m taken with
Submillimetre Common-User Bolometer Array at the James Clerk Maxwell Telescope.
Ammonia emission was found mainly in three clumps located at the south and east
of the position of the compact infrared cluster of AFGL 437, where the CO
outflow seemed to have its origin. One of the NH3(1,1) clumps coincides with
the maximum of NH3(2,2) and with a local peak of emission at 450 {\mu}m. A near
infrared source (s11) is also found at that position. Our continuum map at 2 cm
shows extended elongated emission associated with the infrared source AFGL
437W. This elongated morphology and its spectral index between 3.6 and 2 cm
(\simeq 0.4) suggest the presence of a jet in AFGL 437W. We suggest that
several molecular bipolar outflows may exist in the region. The observed CO
outflow would be the superposition of those individual outflows, which would
explain its low degree of collimation observed at larger scales.
View original:
http://arxiv.org/abs/1111.2595
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