Scaling law for recombination in electron coolers

Experiments on ion-electron recombination in electron coolers show an enhancement of the recombination rate with respect to the standard theory. The theoretical explanation of this effect is an active field of research. Here a parameter-free model is presented in terms of the Vlasov equation. Its inherent scaling rests on two dimensionless variables and agrees with measurements. Additionally, numerical calculations yield the correct magnitude for the enhancement, and trace its cause to the process of beam merging