Ion-atom-atom three-body recombination in cold hydrogen and deuterium plasmas

We present a detailed study about three-body recombination in cold hydrogen and deuterium plasmas based on classical trajectory calculations in hyperspherical coordinates [1,2]. In particular, we study A + A + A⁺→ and A₂⁺ + A  and A + A + A⁺→ and A₂  + A⁺ reactions, where A=H or D. Our results show that the A + A + A⁺→ and A₂⁺ + A reaction is the dominant channel in energies ranging from 100 to 10⁵K. However, when the collision energy is of the same order of magnitude as the dissociation energy of the neutral molecule, A₂, the three-body recombination rate shows a drastic reduction, and a new trend appears. These results are relevant for tokamak physics because they may affect the ultimate divertor detachment and recycling stages.