Charge exchange of H+, H2+, H3+ at energies of 1–30 keV in sodium

Abstract Charge-exchange reactions of H + , H 2 + and H 3 + at energies of 1–30 keV in sodium vapor were studied using the charge-exchange canal of a 2 × 1 MV tandem accelerator. Ion optics simulations were performed before measurements to ensure high beam transport efficiency in the beamline. The density of sodium vapor was calibrated with published attenuation cross-section data of He + -Na. Total attenuation cross sections of all the three species were acquired, among which, the data for H + agree well with the existing data and those for H 2 + , H 3 + were first measured. In the relatively high energy range (above 3 keV/amu), the total attenuation cross-sections appear to be independent of incident ion species; however, the curves for different ion species show different tendencies in the low energy part. Besides, the yields of negative ions were also obtained. It appears that H + is most efficient to produce H − compared with H 2 + and H 3 + .