Measurements of the mutual neutralisation of N+/O- and O+/O-

Mutual neutralisation of N+/O- and O+/O- ions has been measured by an inclined-beams technique for interaction energies between 33 and 2090 eV. At the lower limit the energy range almost overlaps that of the merged-beams experiments described in 1975 by Moseley et al. The present results are at least three times smaller than those of Moseley et al and possible reasons for the discrepancies are discussed. At interaction speeds of greater than 2*105 m s-1 the cross sections for N+/O- and O+/O- converged with recent measurements by Peart and Foster for Na+/O-.