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On the Role of Molecular Hydrogen in Formation and Evolution of Blue Compact Dwarf Galaxies and Giant HII-Regions

  • Yu. I. Izotov
Part of the Astrophysics and Space Science Library book series (ASSL, volume 162)

Abstract

The universal mechanism controlling the thermal evolution of the gas clouds, namely the molecular hydrogen formation, is found. The cloud is effectively cooled from temperature T ≃ 104 K down to T <103 K. The principal possibility has been shown to exist for the blue compact dwarf galaxies formation from matter with primeval chemical composition. In the galaxies with large heavy element abundances Z > 0.2 Zο the star formation regions fragment on the clouds with masses M ≃ 103 − 105 M due to thermal instability. The star formation regions in the galaxies with Z < 0.2 Z are more homogeneous and have the masses ≃ 106 − 107 M.

Keywords

Star Formation Molecular Hydrogen Heavy Element Massive Star Globular Cluster 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic Publishers 1990

Authors and Affiliations

  • Yu. I. Izotov
    • 1
  1. 1.Main Astronomical Observatory of the Academy of Sciences of the Ukrainian SSRKievRussia

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