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Reduction of chemical networks. II. Analysis of the fractional ionisation in protoplanetary discs

D. Semenov·D. Wiebe·Th. Henning
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Abstract

(abridged) We analyse the evolution of the fractional ionisation in a steady-state protoplanetary disc with a vertical temperature gradient and with gas-grain chemistry including surface reactions. The ionisation due to stellar X-rays, stellar and interstellar UV radiation, cosmic rays and radionuclide decay is taken into account. Using our reduction schemes as a tool for the analysis, we isolate small sets of chemical reactions that reproduce the evolution of the ionisation degree at representative disc locations with an accuracy of 50%-100%. Column densities of key molecules are calculated and compared to the results of other recent studies and observational data.

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D. Semenov, D. Wiebe, Th. Henning. 2004-03-23. Reduction of chemical networks. II. Analysis of the fractional ionisation in protoplanetary discs. https://doi.org/10.1051/0004-6361%3A20034128

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