2011ApJ...740..114Z

We report new results on outflow and infall in the star-forming cores W3-SE SMA-1 and SMA-2 based on analysis of ∼2".5 resolution observations of the molecular lines HCN(3-2), HCO⁺(3-2), N₂H⁺(3-2), and CH₃OH(5_2, 3_–41, 3_) with the Submillimeter Array (SMA). A high-velocity bipolar outflow originating from the protostellar core SMA-1 was observed in the HCN(3-2) line, with a projected outflow axis at a position angle of 48°. The detection of the outflow is confirmed from other molecular lines. An inverse P-Cygni profile in the HCN(3-2) line toward SMA-1 suggests that at least one of the double cores accretes matter from the molecular core. A filamentary structure in the molecular gas surrounds SMA-1 and SMA-2. Based on the SMA observations, our analysis suggests that the double pre-stellar cores SMA-1 and SMA-2 result from fragmentation in the collapsing massive molecular core W3-SE, and it is likely that they are forming intermediate- to high-mass stars which will be new members of a star cluster in the W3-SE region.