OUTFLOW-CORE INTERACTION IN BARNARD 1
- Academia Sinica Institute of Astronomy and Astrophysics, P.O. Box 23-141, Taipei 10617, Taiwan (China)
In order to study how outflows from protostars influence the physical and chemical conditions of the parent molecular cloud, we have observed the Barnard 1 (B1) main core, which harbors four Class 0 and three Class I sources, in the CO (J = 1 - 0), CH{sub 3}OH (J{sub K} = 2{sub K} - 1{sub K}), and the SiO (J = 1 - 0) lines using the Nobeyama 45 m telescope. We have identified three CO outflows in this region: one is an elongated ({approx}0.3 pc) bipolar outflow from a Class 0 protostar B1-c in the submillimeter clump SMM 2, another is a rather compact ({approx}0.1 pc) outflow from a Class I protostar B1 IRS in the clump SMM 6, and the other is an extended outflow from a Class I protostar in SMM 11. In the western lobe of the SMM 2 outflow, both the SiO and CH{sub 3}OH lines show broad redshifted wings with the terminal velocities of 25 km s{sup -1} and 13 km s{sup -1}, respectively. It is likely that the shocks caused by the interaction between the outflow and ambient gas enhance the abundance of SiO and CH{sub 3}OH in the gas phase. The total energy input rate by the outflows (1.1 x 10{sup -3} L{sub sun}) is smaller than the energy-loss rate (8.5 x 10{sup -3} L{sub sun}) through the turbulence decay in the B1 main core, which suggests that the outflows cannot sustain the turbulence in this region. Since the outflows are energetic enough to compensate the dissipating turbulence energy in the neighboring, more evolved star-forming region NGC 1333, we suggest that the turbulence energy balance depends on the evolutionary state of the star formation in molecular clouds.
- OSTI ID:
- 21394215
- Journal Information:
- Astrophysical Journal, Vol. 712, Issue 2; Other Information: DOI: 10.1088/0004-637X/712/2/778; ISSN 0004-637X
- Country of Publication:
- United States
- Language:
- English
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