Calculation of electron-impact excitation and ionisation cross sections and reaction rate coefficients for C, N and O atoms

Abstract

This work concerns the calculation of electron-impact excitation and ionisation cross sections and reaction rate coefficients for carbon, nitrogen and oxygen atoms. Several analytical formulas proposed in the literature are used to calculate cross sections and rate coefficients for excitation of optically allowed and parity/spin forbidden transitions and for ionisation from electronic levels of the atoms. Theoretical calculations are then compared with each other and confronted to available experimental cross sections in order to deduce the most accurate analytic rate coefficient formula, which will be used in the implementation of Collisional-Radiative (CR) model for C-N-O-containing plasmas. The cross section and the reaction rate database created will be used in the development of a multi-temperature CR model allowing the determination of the population number densities inside an electric arc generated between two graphite electrodes and dedicated to the synthesis of carbon nanoparticles.