Outflow, Infall and Protostars in the Star Forming Core W3-SE

We report new results on outflow and infall in the star forming cores W3-SE SMA-1 and SMA-2 based on analysis of $\sim 2.5\text{arcsec}$ resolution observations of the molecular lines HCN(3-2), HCO${}^{+}$(3-2), N${}_2$H${}^{+}$(3-2) and CH${}_3$OH(5${}_{2,3}-4_{1,3}$) with the Submillimeter Array. A high-velocity bipolar outflow originating from the proto-stellar core SMA-1 was observed in the HCN(3-2) line, with a projected outflow axis in position angle 48$\text{arcdeg}$. 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 matters 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.