Electron cooling simulation software at BNL
Tech-X at Colorado and BNL collaborated in developing a unique cooling simulation software which derives the friction coefficient for ions moving through a bunch of electrons. The code is based on Tech's VORPAL, which is a platform for various complex, numerical-intensive simulations. The code calculated its result from 'first principles' by repeating the scattering of the ion with many electrons numerous times.
Since there is no approximation in the physics underlying the calculation, this code is highly reliable, if slow. It provides important benchmarking to other cooling dynamics codes, which are faster but which use various approximations. Thus one may develop confidence in the dynamics codes.
Left, comparison of the friction force calculated by the dynamics code BETACOOL (red line) and using VORPAL (green circles) as function of the ion velocity.