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arXiv · 1002.0608

The Mass-Size Relation from Clouds to Cores. I. A new Probe of Structure in Molecular Clouds

J. Kauffmann·T. Pillai·R. Shetty·P. C. Myers·A. A. Goodman
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Abstract

We use a new contour-based map analysis technique to measure the mass and size of molecular cloud fragments continuously over a wide range of spatial scales (0.05 < r / pc < 10), i.e., from the scale of dense cores to those of entire clouds. The present paper presents the method via a detailed exploration of the Perseus Molecular Cloud. Dust extinction and emission data are combined to yield reliable scale-dependent measurements of mass. This scale-independent analysis approach is useful for several reasons. First, it provides a more comprehensive characterization of a map (i.e., not biased towards a particular spatial scale). Such a lack of bias is extremely useful for the joint analysis of many data sets taken with different spatial resolution. This includes comparisons between different cloud complexes. Second, the multi-scale mass-size data constitutes a unique resource to derive slopes of mass-size laws (via power-law fits). Such slopes provide singular constraints on large-scale density gradients in clouds.

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J. Kauffmann, T. Pillai, R. Shetty, P. C. Myers, A. A. Goodman. 2010-02-04. The Mass-Size Relation from Clouds to Cores. I. A new Probe of Structure in Molecular Clouds. https://doi.org/10.1088/0004-637x%2F712%2F2%2F1137

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