Star Formation Relations in Nearby Molecular Clouds
Abstract
We test some ideas for star formation relations against data on local molecular clouds. On a cloud by cloud basis, the relation between the surface density of star formation rate and surface density of gas divided by a free-fall time, calculated from the mean cloud density, shows no significant correlation. If a crossing time is substituted for the free-fall time, there is even less correlation. Within a cloud, the star formation rate volume and surface densities increase rapidly with the corresponding gas densities, faster than predicted by models using the free-fall time defined from the local density. A model in which the star formation rate depends linearly on the mass of gas above a visual extinction of 8 mag describes the data on these clouds, with very low dispersion. The data on regions of very massive star formation, with improved star formation rates based on free-free emission from ionized gas, also agree with this linear relation.
Cite
@article{arxiv.1401.3287,
title = {Star Formation Relations in Nearby Molecular Clouds},
author = {Neal J. Evans and Amanda Heiderman and Nalin Vutisalchavakul},
journal= {arXiv preprint arXiv:1401.3287},
year = {2015}
}
Comments
15 pages, 8 figures, in press in ApJ