We obtain pressure-dependent rate coefficients in dry synthetic air (79% N 2 , 21% O 2) by fitting Pulsed Townsend measurements over a pressure range from 10 to 100 kPa, around the critical density-reduced electric field from 86 to 104 Td. The physical processes are reviewed and set in relation to a suitable kinetic model. A procedure for fitting kinetic reaction rates is described, which is based on finite-volume simulations of charge carrier drift. Electron attachment, ionization and detachment as well as ion conversion rate coefficients are obtained. We find a quadratic pressure dependency in the conversion rate, consistent with three-body collisions, and observe a pressure-dependency in the onset of electron avalanche growth in dry air.

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