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Very cold and massive cores near ISOSS J18364-0221: Implications for the initial conditions of high-mass star-formation

Stephan M. Birkmann·Oliver Krause·Dietrich Lemke
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Abstract

We report the discovery of two very cold and massive molecular cloud cores in the region ISOSS J18364-0221. The object has been identified by a systematic search for very early evolutionary stages of high-mass stars using the 170 micron ISOPHOT Serendipity Survey (ISOSS). Submm continuum and molecular line measurements reveal two compact cores within this region. The first core has a temperature of 16.5 K, shows signs of ongoing infall and outflows, has no NIR or MIR counterpart and is massive enough (M ~ 75 M_sun) to form at least one O star with an associated cluster. It is therefore considered a candidate for a genuine high-mass protostar and a high-mass analog to the Class 0 objects. The second core has an average gas and dust temperature of only ~ 12 K and a mass of M ~ 280 M_sun. Its temperature and level of turbulence are below the values found for massive cores so far and are suggested to represent the initial conditions from which high-mass star formation occurs.

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Stephan M. Birkmann, Oliver Krause, Dietrich Lemke. 2005-09-23. Very cold and massive cores near ISOSS J18364-0221: Implications for the initial conditions of high-mass star-formation. https://doi.org/10.1086/498259

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