The Relationship between Molecular Gas Tracers and Kennicutt-Schmidt Laws

@article{Krumholz2007TheRB,
  title={The Relationship between Molecular Gas Tracers and Kennicutt-Schmidt Laws},
  author={Mark R. Krumholz and Todd A. Thompson},
  journal={The Astrophysical Journal},
  year={2007},
  volume={669},
  pages={289 - 298}
}
We provide a model for how Kennicutt-Schmidt (KS) laws, which describe the correlation between star formation rate and gas surface or volume density, depend on the molecular line chosen to trace the gas. We show that, for lines that can be excited at low temperatures, the KS law depends on how the line critical density compares to the median density in a galaxy's star-forming molecular clouds. High critical density lines trace regions with similar physical properties across galaxy types, and… 

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