Abstract
We observed with the VLA several regions of mass outflow at 20,6 and 2 cm: LkHα 198, GL 490, HH 7-11, TTau, HLTau, GGD 12-15, GL961, GGD27-28, V645Cyg, CepA, and MWC1080. In most of the regions no continuum source was detected, down to the mJy level, at 6 cm that could be identified as the energy source of the outflow. This result suggests that in these cases the stellar winds powering the outflows are either neutral or, if ionized, have a large terminal velocity (∼ 10^2 km s-1) T Tauri and most of the other sources detected show spectra characteristic of an optically-thin H II region and not that of simple ionized winds. We measured the positions of several H2 0 masers associated with mass outflow regions: GL 490, OMC(2)2, OMC(2)1, Mon R2, GGD 12-15, S106, GL 2591, NGC 7129(2), 5140 and Cep A.
