D- production by multiple charge-transfer collisions of low-energy D ions and atoms in cesium vapor

The production of D- by multiple charge-transfer collisions of a D+ beam in a cesium-vapor target is considered for D+ energies above 300 eV. The cross sections relevant to D- formation are obtained by a least-squares fit of three-charge-state differential equations to experimental yield curves. Implications for production of intense negative-ion beams are discussed, and speculations are made about extrapolation to lower engeries