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The properties of molecular clouds with high redshifts (z=2–3)

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This paper deals with molecular clouds discovered in the absorption spectra (z=2–3) of distant quasars. It is argued that these clouds belong to the gaseous subsystems of young galaxies. We estimate the gas concentration to ben<104 cm−3 in the cloud observed in the direction of the quasar PHL957. It is shown that this cloud is exposed to ultraviolet radiation. The UV-energy flux does not exceed the value typical for our Galaxy by an order of magnitude (F≃2×10−6 ergs cm−2 s−1 Å−1 at λ=2000 Å). The mechanisms maintaining the thermal balance in this cloud are discussed.

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Shchekinov, Y.A., Entel, M.B. & Dudenko, A.I. The properties of molecular clouds with high redshifts (z=2–3). Astrophys Space Sci 107, 51–59 (1984). https://doi.org/10.1007/BF00649613

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  • Radiation
  • Absorption Spectrum
  • Ultraviolet Radiation
  • Molecular Cloud
  • High Redshift