Extremely high velocity gas from the massive YSOs in IRAS 17233-3606
  Molecular outflows from high-mass young stellar objects provide an excellent
way to study the star formation process, and investigate if they are scaled-up
versions of their low-mass counterparts. We selected the nearby massive star
forming region IRAS 17233-3606 in order to study the kinematics and physics
along the molecular outflow(s) originating from this source. We observed IRAS
17233-3606 in CO, a typical tracer of gas associated with molecular outflow,
with the Submillimeter Array in the (2-1) transition, and with the APEX
telescope in the higher excitation (6-5) line. Additional infrared H2
observations were performed with the UKIRT telescope. The CO data were analysed
using a LVG approach. Our data resolve the previously detected molecular
outflow in at least three different components, one of them with a high
collimation factor ~4, and characterised by emission at extremely high
velocities (|v-v_{LSR}|>120 km s^{-1}). The estimate of the kinematical outflow
parameters are typical of massive YSOs, and in agreement with the measured
bolometric luminosity of the source. The kinematic ages of the flows are in the
range 10^2-10^3 yr, and therefore point to young objects that still did not
reach the main sequence.
