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arXiv · astro-ph/9711008

Supersonic Random Flows in the Perseus Molecular Cloud

Paolo Padoan·John Bally·Youssef Billawala·Mika Juvela·AAke Nordlund
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Abstract

We compare the statistical properties of J=1-0 13CO spectra observed in the Perseus Molecular Cloud with synthetic J=1-0 13CO spectra from a 5 pc model cloud. The synthetic spectra are computed solving the non-LTE radiative transfer problem for a model cloud obtained as solutions of the 3-D magneto-hydrodynamic (MHD) equations in both the highly supersonic and super-Alfvenic regimes of random flows. We present several statistical results that demonstrate remarkable similarity between real data and the synthetic cloud. The three-dimensional structure and dynamics of molecular clouds like Perseus are appropriately described by random supersonic and super-Alfvenic MHD flows. Although the description of gravity and stellar radiation are essential to understand the formation of single protostars and the effects of star formation in the cloud dynamics, the overall description of the cloud and of the initial conditions for star formation can apparently be described on intermediate scales without accounting for gravity and stellar radiation.

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Paolo Padoan, John Bally, Youssef Billawala, Mika Juvela, AAke Nordlund. 1997-11-03. Supersonic Random Flows in the Perseus Molecular Cloud. https://arxiv.org/abs/astro-ph/9711008

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