How Galaxies Form Stars: The Connection between Local and Global Star Formation in Galaxy Simulations

@article{Semenov2018HowGF,
  title={How Galaxies Form Stars: The Connection between Local and Global Star Formation in Galaxy Simulations},
  author={Vadim A. Semenov and Andrey V. Kravtsov and Nickolay Y. Gnedin},
  journal={The Astrophysical Journal},
  year={2018},
  volume={861}
}
Using a suite of isolated L⋆ galaxy simulations, we show that global depletion times and star-forming gas mass fractions in simulated galaxies exhibit systematic and well-defined trends as a function of the local star formation efficiency per freefall time, , strength of stellar feedback, and star formation threshold. We demonstrate that these trends can be reproduced and explained by a simple physical model of global star formation in galaxies. Our model is based on mass conservation and the… 

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