Mass-density relationship in molecular cloud clumps

作者：Donkov Sava^*; Veltchev Todor V; Klessen Ralf S

来源：Monthly Notices of the Royal Astronomical Society, 2011, 418(2): 916-928.

DOI：10.1111/j.1365-2966.2011.19543.x

• turbulence
• methods: statistical
• ISM: clouds
• ISM: structure

We study the massdensity relationship n ? mx in molecular cloud condensations (clumps), considering various equipartition relations between their gravitational, kinetic, internal and magnetic energies. Clumps are described statistically, with a density distribution that reflects a lognormal probability density function in turbulent cold interstellar medium. The clump massdensity exponent x derived at different scales L varies in most of the cases within the range -2.5 ?x?-0.2, with a pronounced scale dependence and in consistency with observations. When derived from the global sizemass relationship for set of clumps, generated at all scales, the clump massdensity exponent has typical values -3.0 ?x(?glob) ?-0.3 that depend on the forms of energy, included in the equipartition relations, and on the velocity scaling law, whereas the description of clump geometry is important when magnetic energy is taken into account.

• 出版日期2011-12