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Caught in the act: The Onset of massive star formation

H. Beuther·T. K. Sridharan·M. Saito
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Abstract

Combining mid-infrared data from the SPITZER Space Telescope with cold gas and dust emission observations from the Plateau de Bure Interferometer, we characterize the Infrared Dark Cloud IRDC18223-3 at high spatial resolution. The millimeter continuum data reveal a massive `184Msun gas core with a projected size of ~28000AU that has no associated protostellar mid-infrared counterpart. However, the detection of 4.5mum emission at the edge of the core indicates early outflow activity, which is supported by broad CO and CS spectral line-wing emission. Moreover, systematically increasing N2H+(1-0) line-width toward the mm core center can be interpreted as additional evidence for early star formation. Furthermore, the N2H+(1-0) line emission reveals a less massive secondary core which could be in an evolutionary stage prior to any star formation activity.

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H. Beuther, T. K. Sridharan, M. Saito. 2005-10-18. Caught in the act: The Onset of massive star formation. https://doi.org/10.1086/498867

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