Abstract
In various laboratory experiments chemical processes induced by ionizing radiation have been simulated which occur in the outer layers of comets, in interstellar clouds, and in the atmospheres of planets and moons of our Solar System. An obvious problem for the interpretation of the results is that the duration of the experiments is by many orders of magnitude shorter than the time intervals of the simulated systems. Hence in most ice and gas phase experiments much higher dose rates of ionizing radiation are applied in order to obtain a total absorbed dose which is realistic for the simulated system.
In this paper the influence of the dose rate on reactions in gaseous systems shall be discussed as well as the influence of linear energy transfer and of scavengers on the reactions and their yields. The central parameter is the density of reactive species.
Some consequences for ice systems will be given.
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Sack, N.J. The importance of radical density in cosmic chemistry. Earth Moon Planet 46, 135–148 (1989). https://doi.org/10.1007/BF00054955
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DOI: https://doi.org/10.1007/BF00054955