Charge-changing cross sections for 1—25-keVH(1s)incident on a Na-vapor target

Abstract

Measurements of the charge-changing cross sections ${\ensuremath{\sigma}}_{g\ensuremath{-}}$ and ${\ensuremath{\sigma}}_{g+}$ are reported for 1-25-keV fast $\mathrm{H}(1s)$ atoms incident on a Na-vapor target. The cross section ${\ensuremath{\sigma}}_{g\ensuremath{-}}$ falls from 3\ensuremath{'}${10}^{\ensuremath{-}15}$ ${\mathrm{cm}}^{2}$ at 1 keV to 3.5\ensuremath{'}${10}^{\ensuremath{-}18}$ ${\mathrm{cm}}^{2}$ at 25 keV. The cross section ${\ensuremath{\sigma}}_{g+}$ rises from 1.1\ensuremath{'}${10}^{\ensuremath{-}17}$ ${\mathrm{cm}}^{2}$ at 2 keV to 1.5\ensuremath{'}${10}^{\ensuremath{-}15}$ ${\mathrm{cm}}^{245}$ at 25 keV. Measured values of the equilibrium fractions ${F}_{\ensuremath{-}}^{\ensuremath{\infty}}$ and ${F}_{+}^{\ensuremath{\infty}}$ for incident ${\mathrm{H}}^{\ensuremath{-}}$ ions are also presented.