HERBIG-HARO OBJECTS IN THE RHO-OPHIUCHI CLOUD

Using deep, narrow-band images of the main rho Oph dark cloud centered on the wavelengths of Ha and [S II], we present evidence for three ne w Herbig-Haro objects. This increases the total number in the cloud to five. In addition, positions for five candidate Herbig-Haro objects a re given. Relatively high [S II]/H alpha ratios indicate low excitatio n conditions for all of these nebulae. We list potential exciting star s for each Herbig-Haro object and candidate by identifying nearby youn g stellar objects with strong infrared excesses and/or millimeter cont inuum emission. The location of most of these nebulae near the cloud e dges underscores the important role that extinction by dust plays in t he rho Oph cloud in masking the presence of Herbig-Haro objects. Among the newly identified Herbig-Haro objects is a jet-like string of emis sion nebulae emanating from the classical T Tauri star SR 4. [S II] em ission is also found coincident with a knot of strong molecular hydrog en emission associated with the highly collimated VLA 1623 molecular o utflow. Indeed, the low-excitation nature of all of the objects in our study, coupled with the high extinction of the cloud, suggests that a deep survey for shocked molecular hydrogen at lambda=2.122 mu m would be the best way to search for evidence of strong winds from the large population of young stellar objects in the cloud.