Giant protostellar outflows revealed by infrared imaging

We present new infrared data from a survey for embedded protostellar jets i n the Orion A cloud. This survey makes use of the S(1) v = 1-0 line of mole cular hydrogen at lambda = 2.12 mu m to search for infrared jets deep insid e the cloud and thus hidden from view at optical wavelengths. We present da ta on the three flows associated with the Herbig-Haro objects HH 43/38 & HH 64, HH 65, and the L1641-N giant flow. HH 43, HH 38 and HH 64 are part of one H-2 flow extending over at least 1.4 pc. We identify a deeply embedded 1.3 mm and IRAS source (HH 43 MMS 1 = IRAS 05355-0709C) as the likely drivi ng source, while the infrared source previously assumed to drive HH 43/38 ( HH 43-IRS 1 = IRAS 05357-0710) is seen to drive a smaller jet. The morpholo gy of HH 43-IRS 1 suggests that it is a star+disk system seen close to edge -on. We identify another large H-2 flow apparently comprising the L1641-S3 CO outflow and the redshifted lobe of the L1641-S CO outflow containing HH 65. This how extends over at least 2.6 pc and appears strongly curved. It i s driven by L1641-S3 IRS, a deeply embedded 1.3 mm and IRAS source (L1641-S 3 MMS 1 = IRAS 05375-0731). Finally, we have found some additional large H- 2 features to the east of V 380 Ori and the HH 1/2 system, which probably o utline another part of the L1641-N outflow. The molecular flow MB 20/21, wh ich extends to the south from V 380 Ori, also appears to be a part of the L 1641-N outflow.