Laboratory measurements of excitation coefficients for five transitions in nitrogen V

Abstract

An experimental method for the determination of the electron impact excitation coefficients is described. This requires the measurement of the absolute intensities of spectral lines emitted by a plasma in the extreme ultraviolet and the determination of the electron temperature of the plasma by a laser scattering technique. Results are presented for five transitions in four times ionized nitrogen. These are corrected for the effect of stepwise excitation and opacity and then compared with values that have been calculated theoretically. The final results are in agreement with the theory to within the experimental uncertainty which is +or-20% for relative values and +or-50% for absolute values.