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On the photochemical formation of CN, C2, and C3 radicals in cometary comae

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The formation of cometary CN, C2 and C3 radicals is investigated in a photochemical reaction scheme. From an analysis of the observed brightness profiles of these radicals, it is shown that CN is formed as a primary product in the photolysis of its parent molecules, whereas C2 and C3 are formed via two-step photodissociation of their parents. We suggest that major parent of C2 is different species from those of CN and C3 on the basis of the difference of the variation with heliocentric distance of the sublimation rate of the parents of these radicals. Parent molecules and reaction schemes for the formation of these radicals are discussed.

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Yamamoto, T. On the photochemical formation of CN, C2, and C3 radicals in cometary comae. The Moon and the Planets 24, 453–463 (1981).

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  • Photodissociation
  • Reaction Scheme
  • Photochemical Reaction
  • Heliocentric Distance
  • Parent Molecule