High Velocity Outflow in CO J=7-6 from the Orion Hot Core
  Using the Caltech Submillimeter Observatory 10.4-meter telescope, we
performed sensitive mapping observations of 12CO J=7-6 emission at 807 GHz
towards Orion IRc2. The image has an angular resolution of 10", which is the
highest angular resolution data toward the Orion Hot Core published for this
transition. In addition, thanks to the on-the-fly mapping technique, the
fidelity of the new image is rather high, particularly in comparison to
previous images. We have succeeded in mapping the northwest-southeast
high-velocity molecular outflow, whose terminal velocity is shifted by ~70-85
km/s with respect to the systemic velocity of the cloud. This yields an
extremely short dynamical time scale of ~900 years. The estimated outflow mass
loss rate shows an extraordinarily high value, on the order of 10^{-3} Msun/yr.
Assuming that the outflow is driven by Orion IRc2, our result agrees with the
picture so far obtained for a 20 Msun (proto)star in the process of formation.
