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On the spectrum of a gaseous nebula of pure hydrogen, II

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Calculations of the optical continuum of a nebula of pure hydrogen were carried out, taking into account, together, with the recombination emission, the two-photon emission and the continuous emission in the reaction of formation of the negative ion of hydrogen. It is found that these processes become predominant when thermal collisions are responsible for the excitation of the nebula. Mixed conditions of excitation, that is by both radiation and collisions, have also been studied. The optical continuum is found to be very sensitive to the excitation conditions, so that a very small contribution of collisional ionizations to the total number of ionizations is sufficient to sensibly modify the appearance of the continuum.

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Gerola, H., Panagia, N. On the spectrum of a gaseous nebula of pure hydrogen, II. Astrophys Space Sci 8, 120–135 (1970). https://doi.org/10.1007/BF00651662

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  • Hydrogen
  • Radiation
  • Recombination
  • Mixed Condition
  • Small Contribution