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arXiv · 1412.4500

Synchrotron radiation from molecular clouds

A. W. Strong·C. Dickinson·E. J. Murphy
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Abstract

Observations of the properties of dense molecular clouds are critical in understanding the process of star-formation. One of the most important, but least understood, is the role of the magnetic fields. We discuss the possibility of using high-resolution, high-sensitivity radio observations to measure the in-situ synchrotron radiation from these molecular clouds. If the cosmic-ray particles penetrate clouds as expected, then we can measure the B-field strength directly using radio data. So far, this signature has never been detected from the collapsing clouds themselves and would be a unique probe of the magnetic field. Dense cores are typically ~0.05 pc in size, corresponding to ~arcsec at ~kpc distances, and flux density estimates are ~mJy at 1 GHz. They should be detectable, for example with the Square Kilometre Array.

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A. W. Strong, C. Dickinson, E. J. Murphy. 2014-12-15. Synchrotron radiation from molecular clouds. https://arxiv.org/abs/1412.4500

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