Eur. Phys. J. D (2013) 67: 234
https://doi.org/10.1140/epjd/e2013-40401-2

Regular Article

Electron attachment to oxygen in nitrogen buffer gas at atmospheric pressure

¹ Department of Experimental Physics, Comenius University, Mlynska dolina F2, 84248 Bratislava, Slovakia
² Chemistry Department, Siedlce University, 3 Maja 54, 08-110 Siedlce, Poland
³ Leibniz Institute for Plasma Science and Technology, Felix-Hausdorff-Str. 2, 17489 Greifswald, Germany

^a e-mail: stano@fmph.uniba.sk

Received: 9 July 2013
Received in final form: 12 September 2013
Published online: 15 November 2013

Abstract

We have carried out experimental and theoretical studies of three body electron attachment (TBEA) to O₂ in N₂/O₂ mixtures. We have applied three different experimental methods to determine the apparent rate constant k for TBEA to O₂ for reduced electric fields E / n from 0.5 Td up to 4.5 Td and O₂ concentrations from 0.02% up to 3%. From the apparent rate constant k we have evaluated three body rate constant for electron attachment to O₂ in pure O₂ (k_O₂) and in pure N₂ (k_N₂). The comparison of present data with former studies shows that the former values of k_N₂ overestimated the efficiency of this reaction, while in case of k_O₂ we have found agreement with earlier studies. We have solved numerically the Boltzmann equation of the electrons and calculated the values of k, k_N₂ and k_O₂ using well established cross sections. Using the known collision cross section set for TBEA to O₂, very good agreement between calculated and measured results for k_O₂ was found, while in the case of k and k_N₂ we had to introduce a scaling function, which describes the decrease of the efficiency of TBEA to O₂ in presence of N₂ and the dependence of the scaling function on E/n was determined.