Dense Cores and Molecular Outflows in the OMC‐2/3 Region

Abstract

We have observed the OMC-2/3 region in the H13CO+(1-0), HCO+(1-0), and CO(1-0) lines by using the Nobeyama 45 m radio telescope. We have identified 18 dense cores in H13CO+ and eight molecular outflows in CO and HCO+ in OMC-2/3. Four of these outflows are newly found. The line widths of the H13CO+ cores in OMC-2/3 are twice as large as those in dark clouds, and the momentum fluxes (flow = Pflow/τD = flowVflow) of the outflows in OMC-2/3 are approximately 2 orders of magnitude larger than those of outflows in dark clouds. We found that the mass-loss rate of the outflow is proportional to the third power of the core velocity dispersion, which suggests that the outflow mass-loss rate is proportional to the mass infall rate onto the protostar. From a comparison between the properties of cores associated with protostars and those without protostars, we suggest that the dissipation of turbulence initiates star formation.