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arXiv · 1506.05472

The initial conditions of stellar protocluster formation. II. A catalogue of starless and protostellar clumps embedded in IRDCs in the Galactic longitude range 15<l<55

A. Traficante·G. A. Fuller·N. Peretto·J. E. Pineda·S. Molinari
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Abstract

We present a catalogue of starless and protostellar clumps associated with infrared dark clouds (IRDCs) in a 40 degrees wide region of the inner Galactic Plane (b<1). We have extracted the far-infrared (FIR) counterparts of 3493 IRDCs with known distance in the Galactic longitude range 15 10^4$ M_sun in mass and up to 10^5 L_sun in luminosity. The mass-radius distribution shows that almost 30% of the starless clumps identified in this survey could form high-mass stars, however these massive clumps are confined in only ~4% of the IRDCs. Assuming a minimum mass surface density threshold for the formation of high-mass stars, the comparison of the numbers of massive starless clumps and those already containing embedded sources suggests an upper limit lifetime for the starless phase of 10^5 years for clumps with a mass M>500 M_sun.

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A. Traficante, G. A. Fuller, N. Peretto, J. E. Pineda, S. Molinari. 2015-06-17. The initial conditions of stellar protocluster formation. II. A catalogue of starless and protostellar clumps embedded in IRDCs in the Galactic longitude range 15<l<55. https://arxiv.org/abs/1506.05472

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