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arXiv · 0908.1549

Anchoring Magnetic Field in Turbulent Molecular Clouds

Hua-bai Li·C. Darren Dowell·Alyssa Goodman·Roger Hildebrand·Giles Novak
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Abstract

One of the key problems in star formation research is to determine the role of magnetic fields. Starting from the atomic inter-cloud medium (ICM) which has density nH ~ 1 per cubic cm, gas must accumulate from a volume several hundred pc across in order to form a typical molecular cloud. Star formation usually occurs in cloud cores, which have linear sizes below 1 pc and densities nH2 > 10^5 per cubic cm. With current technologies, it is hard to probe magnetic fields at scales lying between the accumulation length and the size of cloud cores, a range corresponds to many levels of turbulent eddy cascade, and many orders of magnitude of density amplification. For field directions detected from the two extremes, however, we show here that a significant correlation is found. Comparing this result with molecular cloud simulations, only the sub-Alfvenic cases result in field orientations consistent with our observations.

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Hua-bai Li, C. Darren Dowell, Alyssa Goodman, Roger Hildebrand, Giles Novak. 2009-08-11. Anchoring Magnetic Field in Turbulent Molecular Clouds. https://doi.org/10.1088/0004-637x/704/2/891

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