Dissociative recombination and low-energy inelastic electron collisions   of the helium dimer ion
  This paper reports results from an experimental investigation of the dissociative recombination (DR) of the helium dimer ions at the heavy-ion Test Storage Ring (TSR) in Heidelberg, observing neutral products from electron-ion collisions in a merged beams configuration at relative energies from near-zero (thermal electron energy about 10 meV) up to 40 eV. 
H. B. Pedersen, H. Buhr, S. Altevogt, V. Andrianarijaona, H. Kreckel,   L. Lammich, N. de Ruette, E. M. Staicu-Casagrande, D...