Measurement of H-, H0, and H+ yields produced by foil stripping of 800-MeV H- ions.

Abstract

Measurements of ${\mathrm{H}}^{\ensuremath{-}}$ stripping and ${\mathrm{H}}^{0}$ excited-state production for a wide range of foil thicknesses and experimental conditions are reported. An 800-MeV ${\mathrm{H}}^{\ensuremath{-}}$ beam was passed through carbon or aluminum oxide foils of thicknesses ranging from 10 to 550 \ensuremath{\mu}g/${\mathrm{cm}}^{2}$ and the excited states produced were analyzed by field stripping in a special magnet downstream of the foil. The foil thicknesses were independently determined. The ${\mathrm{H}}^{0}$ atoms emerging in excited states with $ng2$ can be stripped to protons in fields of up to 1.3 T. The yield of excited states as a function of foil thickness and the cross sections for the various interactions are presented. The cross-section ratio of double to single ionization of ${\mathrm{H}}^{\ensuremath{-}}$ in carbon is found to be (1.8\ifmmode\pm\else\textpm\fi{}0.9)%.