Electron emission from foils induced by heavy-ion collisions

Abstract
Absolute double differential yield per ion has been calculated for forward and backward electron emission produced by collisions of highly charged uranium ions with carbon foil of varying thicknesses. A Monte Carlo method has been developed which employs multiple ionization of the carbon and subsequent energy and angular straggling of freed electrons through the foil. A comparison with experimental double differential electron emission yields shows general agreement. Calculated total electron emission is in agreement with experiment at 44 mu g cm-2 as well as the results of Rothard et al. (1990). In addition, the radial distribution of energy deposited by the electrons as they pass through the foil has been calculated. Comparison with the radial dose data of Toburen et al. (1989) shows qualitative agreement. The radial dose calculations were also performed for two different cases having the same stopping power (1 MeV/u U23+ and 21 MeV/u U67+) in order to test the supposition that the radial dose distribution is inversely related to the square of the radial distance (Kellerer, 1977).