The giant molecular outflow in MON R2

A large, massive outflow associated with the Mon R2 infrared cluster has been identified and mapped. The outflow line components are found to be well separated in velocity from the ambient cloud line component. These 'detached wings' suggest high optical depths and filling factors that may be characteristic of old, evolved flows. The blueshifted lobe shows evidence of shell structure similar to that seen in the L1551 outflow. The redshifted lobe is spatially more confined in the plane of the sky and its structure is uncertain. A dense, flattened, rotating core is found near the origin of the bipolar outflow. The physical properties of this core are consistent with magnetized collapsing cloud models. The derived dynamical mass of the core, roughly 1013 solar masses, is supercritical by a factor of about 10. The large-scale velocity structure of the cloud do not appear to be consistent with such angular momentum conservation. (C.D.)