Dense Axion Stars.

@article{Braaten2016DenseAS,
  title={Dense Axion Stars.},
  author={Eric Braaten and Abhishek Ray Mohapatra and Hong Fei Zhang},
  journal={Physical review letters},
  year={2016},
  volume={117 12},
  pages={
          121801
        }
}
If the dark matter particles are axions, gravity can cause them to coalesce into axion stars, which are stable gravitationally bound systems of axions. In the previously known solutions for axion stars, gravity and the attractive force between pairs of axions are balanced by the kinetic pressure. The mass of these dilute axion stars cannot exceed a critical mass, which is about 10^{-14}M_{⊙} if the axion mass is 10^{-4}  eV. We study axion stars using a simple approximation to the effective… 

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