Yu-Nung Su, Sheng-Yuan Liu, Huei-Ru Chen, Ya-Wen Tang
We have imaged the extremely high-velocity outflowing gas in CO (2-1) and
(3-2) associated with the shell-like ultracompact HII region G5.89-0.39 at a
resolution of ~3" (corresponding to ~4000 AU) with the Submillimeter Array. The
integrated high-velocity (>45 km/s) CO emission reveals at least three
blueshifted lobes and two redshifted lobes. These lobes belong to two outflows,
one oriented N-S, the other NW-SE. The NW-SE outflow is likely identical to the
previously detected Br_gamma outflow. Furthermore, these outflow lobes all
clearly show a Hubble-like kinematic structure. For the first time, we estimate
the temperature of the outflowing gas as a function of velocity with the large
velocity gradient calculations. Our results reveal a clear increasing trend of
temperature with gas velocity. The observational features of the extremely
high-velocity gas associated with G5.89-0.39 qualitatively favor the jet-driven
bow shock model.
View original:
http://arxiv.org/abs/1112.2041
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