(CO)-C-13 AND HCO+ OBSERVATIONS OF IRAS SOURCES IN L1641

Twenty-eight IRAS sources selected from the Infrared Astronomical Satellite (IRAS) co-added images in L1641 were observed in the (CO)-C-13 (J = 1-0) and HCO+(J = 1-0) using the 45 m telescope at the Nobeyama Radio Observatory. The (CO)-C-13 and HCO+ column densities toward the IRAS sources correlated with each other, and both column densities also correlated with the IRAS color defined by the 12-25 mum flux ratio. Three outflow sources mapped in this study showed well-defined HCO+ cores with a size of 0.1 pc and a mass of 3-30 M.. The most probable explanation of these results is that the molecular dense cores are dissipated by both accretion and outflow during an early stage of stellar evolution.