New measurements of the mutual neutralisation of H⁺/H⁻and He⁺/H⁻ions

New measurements are presented for the mutual neutralisation of H + /H - ions in the energy (centre-of-mass, CM) range 30-2000 eV and for He + /H - ions in the range 100-3000 eV. The results for He + /H - agree well with earlier measurements by Gaily and Harrison (1970) and by Peart et al. (1970) but the results for H + /H - differ substantially from those published by Moseley et al. (1976), Rundel et al. (1964) Gaily and Harrison and Peart et al. The new results are, however, in good accord with theory and with those of a recent experiment by Szucs et al. (1984).