Self‐similar polytropic champagne flows in H ii regions

  title={Self‐similar polytropic champagne flows in H ii regions},
  author={Ren-Yu Hu and Yu-qing Lou},
  journal={Monthly Notices of the Royal Astronomical Society},
  • Ren-Yu Hu, Y. Lou
  • Published 15 August 2008
  • Physics
  • Monthly Notices of the Royal Astronomical Society
We explore large-scale hydrodynamics of H II regions for various self-similar shock flows of a polytropic gas cloud under self-gravity and with quasi-spherical symmetry. We formulate cloud dynamics by invoking specific entropy conservation along streamlines and obtain global self-similar ‘champagne flows’ for a conventional polytropic gas with shocks as a subclass. Molecular cloud cores are ionized and heated to high temperatures after the onset of nuclear burning of a central protostar. We… 
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