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MHD Turbulence in Star-Forming Clouds

Mordecai-Mark Mac Low·Ralf Klessen·Fabian Heitsch
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Abstract

We review how supersonic turbulence can both prevent and promote the collapse of molecular clouds into stars. First we show that decaying turbulence cannot significantly delay collapse under conditions typical of molecular clouds, regardless of magnetic field strength so long as the fields are not supporting the cloud magnetohydrostatically. Then we review possible drivers and examine simulations of driven supersonic and trans Alfvénic turbulence, finally including the effects of self-gravity. Our preliminary results show that, although turbulence can support regions against gravitational collapse, the strong compressions associated with the required velocities will tend to promote collapse of local condensations.

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Mordecai-Mark Mac Low, Ralf Klessen, Fabian Heitsch. 1999-11-03. MHD Turbulence in Star-Forming Clouds. https://arxiv.org/abs/astro-ph/9911048

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