Subarcsecond imaging of SiO in the HH 211 protostellar jet

We present images of the HH 211 molecular jet in the SiO v = 0, J = 1-0 lin e at 43 GHz made with the Very Large Array at approximately 0."5 resolution . The SiO emission appears to trace primarily internal bow shocks in the ou tflow, suggesting that the dust and molecular gas are accelerated via promp t entrainment at internal working surfaces in the jet. There is also some e vidence for limb brightening of the SiO emission, indicating that SiO emiss ion may also arise from entrainment in the jet's boundary layer. Excitation temperatures of greater than or similar to 150-200 K are inferred from the SiO emission. Enhancements in the SiO abundance of similar to 10(6) over i nterstellar values are observed, and the possible origin of the SiO is disc ussed.