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arXiv · 1203.3363

Clump mass function at an early stage of molecular cloud evolution: I. A statistical approach

Sava Donkov·Todor V. Veltchev·Ralf S. Klessen
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Abstract

We derive the mass function of condensations (clumps) which were formed through a turbulent cascade over a range of spatial scales $L\le20$ pc during early, predominantly turbulent evolution of a molecular cloud. The approach rests upon the assumption of a statistical clump mass-density relationship $n\propto m^x$ with a scale dependence of the exponent $x$ obtained from equipartition relations between various forms of energy of clumps. The derived clump mass function (ClMF) could be represented by series of 2 or 3 power laws, depending on the chosen equipartition relation, the velocity scaling index and the type of turbulent forcing. The high-mass ClMF exhibits an average slope $Γ\simeq-1$, typical for fractal clouds, whereas its intermediate-mass part is shallower or flattened, in agreement with some observational studies.

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Sava Donkov, Todor V. Veltchev, Ralf S. Klessen. 2012-03-15. Clump mass function at an early stage of molecular cloud evolution: I. A statistical approach. https://doi.org/10.1111/j.1365-2966.2012.20939.x

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