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arXiv · 1005.1714

The COMPLETE Survey of Outflows in Perseus

Hector G. Arce·Michelle A. Borkin·Alyssa A. Goodman·Jaime E. Pineda·Michael W. Halle
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Abstract

We present a study on the impact of molecular outflows in the Perseus molecular cloud complex using the COMPLETE survey large-scale 12CO(1-0) and 13CO(1-0) maps. We used three-dimensional isosurface models generated in RA-DEC-Velocity space to visualize the maps. This rendering of the molecular line data allowed for a rapid and efficient way to search for molecular outflows over a large (~ 16 sq. deg.) area. Our outflow-searching technique detected previously known molecular outflows as well as new candidate outflows. Most of these new outflow-related high-velocity features lie in regions that have been poorly studied before. These new outflow candidates more than double the amount of outflow mass, momentum, and kinetic energy in the Perseus cloud complex. Our results indicate that outflows have significant impact on the environment immediately surrounding localized regions of active star formation, but lack the energy needed to feed the observed turbulence in the entire Perseus complex. This implies that other energy sources, in addition to protostellar outflows, are responsible for turbulence on a global cloud scale in Perseus. We studied the impact of outflows in six regions with active star formation within Perseus of sizes in the range of 1 to 4 pc. We find that outflows have enough power to maintain the turbulence in these regions and enough momentum to disperse and unbind some mass from them. We found no correlation between outflow strength and star formation efficiency for the six different regions we studied, contrary to results of recent numerical simulations. The low fraction of gas that potentially could be ejected due to outflows suggests that additional mechanisms other than cloud dispersal by outflows are needed to explain low star formation efficiencies in clusters.

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Hector G. Arce, Michelle A. Borkin, Alyssa A. Goodman, Jaime E. Pineda, Michael W. Halle. 2010-05-11. The COMPLETE Survey of Outflows in Perseus. https://doi.org/10.1088/0004-637x%2F715%2F2%2F1170

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