Shocked molecular hydrogen and jets in star-forming clouds. II

Extensive mapping is presented of the 2.12 micron v = 1 - 0 S(1) line of molecular hydrogen in NGC 2071, located in the Orion molecular cloud, and HH 12, located in the NGC 1333 cloud in Perseus. In NGC 2071, the outflow is shown to be confined to two narrow, oppositely directed jets of gas emerging from the recently formed cluster of stars. The strongest of five emission peaks in this source occurs at the outer boundary of the high-velocity flow region mapped in CO. An additional observation provides supporting evidence for the existence of a massive circumstellar disk around NGC 2071. In HH 12, the S(1) line emission is closely correlated with the optical Herbig-Haro nebulosity, and peaks in the north. A new method for computing the mass-loss rate and wind velocity of the driving engine responsible for collimated outflows is demonstrated. 78 references