Formation of Subgalactic Clouds under Ultraviolet Background Radiation

  title={Formation of Subgalactic Clouds under Ultraviolet Background Radiation},
  author={Tetsu Kitayama and Satoru Ikeuchi},
  journal={The Astrophysical Journal},
  pages={615 - 634}
The effects of the ultraviolet (UV) background radiation on the formation of subgalactic clouds are studied by means of one-dimensional hydrodynamical simulations. The radiative transfer of the ionizing photons caused by the absorption by H I, He I, and He II, neglecting the emission, is explicitly taken into account. We find that the complete suppression of collapse occurs for the clouds with circular velocities typically in the range Vc ~ 15-40 km s-1 and the 50% reduction in the cooled gas… 

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