Aperture synthesis observations of CO outflows in low-mass star forming regions
We have made aperture synthesis observations of the CO outflows associated with low-mass young stellar objects using the Nobeyama Millimeter Array. Our angular resolution is 5–8″, which corresponds to 850–2100 AU.
We have detected both blueshifted and redshifted CO emission in B335, L483, L723, L1527, TMC1A and VLA1623, while only blueshifted on in B1. The CO emission generally peaks at 1000–3000 AU offset from the central source and is rather weak at the position of the central source. The only exception is the CO outflow in VLA1623, which shows strong blueshifted emission at the position of the mm-continuum source. Such centrally peaked distribution of the CO emission suggests that the outflow in VLA1623 is in the earliest stage of its evolution.
Morphological characteristics such as biconical shape in B335 and in L1527 and quadrupolar-like structure in L723 are clearly seen in our interferometer maps. This suggests that the morphology of the CO outflows has been settled within a few thousand AU of their origin.
KeywordsContinuum Emission Spectral Energy Distribution Central Source IRAS Source Aperture Synthesis
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