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The protostellar outflow HH211 is of considerable interest since it isextremely young and highly collimated. Here, we explore the outflow throughimaging and spectroscopy in the near-infrared to determine if there are furtherdiagnostic signatures of youth. We confirm the detection of a near-infraredcontinuum of unknown origin. We propose that it is emitted by the drivingmillimeter source, escapes the core through tunnels, and illuminates featuresaligning the outflow. Narrow-band flux measurements of these features containan unusually large amount of continuum emission. [Fe II] emission has beendetected and is restricted to isolated condensations. However, thecharacteristics of vibrational excitation of molecular hydrogen resemble thoseof older molecular outflows. We attempt to model the ordered structure of thewestern outflow as a series of shocks, finding that bow shocks with J-typedissociative apices and C-type flanks are consistent. Moreover, essentially thesame conditions are predicted for all three bows except for a systematicreduction in speed and density with distance from the driving source. We findincreased K-band extinctions in the bright regions as high as 2.9 magnitudesand suggest that the bow shocks become visible where the outflow impacts ondense clumps of cloud material. We propose that the outflow is carved out byepisodes of pulsating jets. The jets, driven by central explosive events, areresponsible for excavating a central tunnel through which radiation temporarilypenetrates.Comment: 12 pages, 9 figure

The near-infrared excitation of the HH 211 protostellar outflow