| Description |
The main goal of this project is to estimate the luminosity of the high-mass
protostar IRAS20126+4104 and obtain a direct measurement of the mass loss
rate of the associated bipolar outflow. This is a well studied object, where
a 7 Msun protostar is surrounded by a Keplerian disk and powers a bipolar
outflow. The relatively small distance (1.64 kpc) and the limited complexity
of the surroundings of this object, combined with the unique angular
resolution of HERSCHEL in the far-IR, make it possible to reconstruct the
spectral energy distribution and thus obtain an accurate estimate of the
stellar luminosity. Knowledge of the mass and luminosity will set constraints
on the evolutionary stage of the young stellar object. We also want to
observe the OI 63 micron line which is strictly related to the mass los rate
of the outflow. The latter can thus be obtained independent of the usual
drawbacks (uncertain molecular abundance, unknown outflow inclination angle)
of the estimates obtained from CO and other typical outflow tracers.
Moreover, since the outflow is precessing, one can also relate the position
along the outflow with the time of ejection and reconstruct the mass loss
rate history of this object. We will also observe the OI 145 micron line to
verify possible opacity effects in the 63 micron line, from the ratio between
the two lines. These data will be complemented with observations of the CI
line to image possible photo dissociation regions, plus a number of CO lines
observed with SPIRE, PACS, and HIFI, to reconstruct the excitation structure
of the outflow, both in space and velocity. |
