The Complete Survey of Outflows in Perseus

Abstract

We present a study on the impact of molecular outflows in the Perseus molecular cloud complex using the COMPLETE survey large-scale 12 CO(1-0) and 13 CO(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 deg 2 ) 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.

APEX-CHAMP+high-JCO observations of low-mass young stellar objects

“…FCRAO: 12 CO 1-0 spectrum of IRAS 4A is extracted from COMPLETE survey map (Arce et al 2010) observed with FCRAO. Table 2 summarizes the list of observed lines for each instrument.…”

Radiation-Hydrodynamic Simulations of Protostellar Outflows: Synthetic Observations and Data Comparisons

“…On these scales, outflows powerfully impact their environment and potentially inject significant energy back into the parent molecular cloud (Matzner & McKee 1999). This feedback may be partially responsible for maintaining turbulence on 0.1-1 pc scales (Nakamura & Li 2007;Swift & Welch 2008;Arce & Sargent 2005;Arce et al 2010).…”

“…This means that observed outflow gas may only span the previous few thousand years of the flow. In addition, the ambient lowdensity, high-line-width cloud gas ( 10 km s −1 ) along the line of sight makes identification of a wide-angle, low-velocity outflow component problematic (e.g., Arce et al 2010).…”

Observations of Winds, Jets, and Turbulence Generation in GMCs

“…Outflow feedback may be responsible for sculpting the cloud and may inject sufficient energy and momentum to maintain a quasi-balance between star formation and turbulent energy dissipation. Surveys of HH objects (Walawender et al 2005) and outflows (Arce et al 2010) over the entire Perseus cloud show that while outflows may self-regulate star formation on parsec scales, they would require 10 to 100 collapse time-scales to supply the observed motions on the 30 pc scale of the entire cloud.…”