VLA OBSERVATIONS OF HIGH-VELOCITY H I-ASSOCIATED WITH THE HERBIG-HARO OBJECTS 7-11

We report VLA observations of the 21 cm hyperfine transition of H I and of the adjacent continuum toward the HH 7-11 region. At the velocity of the cloud we detect two H I emission zones that are associated with SVS 3 and BD +30°549, the young stars that illuminate the reflection nebula NGC 1333. We suggest that these are photodissociated H I regions. At intermediate velocities (±20 km s-1 with respect to the radial velocity of the ambient cloud) we detect H I bipolar outflows associated with HH 7-11 and HH 12. The H I outflow morphologies are similar to those observed previously in CO, although we better resolve the second bipolar outflow (the one associated with HH 12). None of the proposed exciting sources of the HH 12 outflow is located at the centroid of the bipolar H I outflow. The HH objects 7-11 and 12 appear projected along the edge of their respective blueshifted H I lobes. This result may imply that these HH objects are not necessarily jetlike phenomena but instead trace the walls of the cavity produced by the stellar wind. In the 20 km s-1 blueshifted channel we also detect several other sites of intermediate-velocity emission whose origin is uncertain but that may signal additional outflow sites, of monopolar geometry, in the cloud. At higher velocities (±40 km s-1 with respect to the radial velocity of the ambient cloud), we can still detect the high-velocity bipolar H I emission associated with HH 7-11. The +40 km s-1 H I emission lobe is more compact than the +20 km s-1 H I emission lobe, as expected for a decelerating outflow. We conclude that the H I mapped with the VLA is the decelerated, lower velocity extension of the extremely high-velocity atomic gas detected by Lizano et al. with Arecibo.