Dissociative recombination and excitation of D5+ by collisions with low-energy electrons

Abstract

We report results from high-resolution studies of D5+ cluster ion collisions with low-energy electrons performed in a heavy ion storage ring. Absolute dissociative recombination (DR) and dissociative excitation (DE) cross sections were determined for the energy range from 0.0005 to 20 eV. The DR cross sections were exceedingly large at low energies, and DR resulted in efficient internal energy redistribution and pronounced fragmentation with two main product channels: D2+3D (0.62 ± 0.03) and 2D2+D (0.35 ± 0.01). The DR and DE cross sections were comparable in the energy range from 0.2 to 20 eV, which suggest that the two processes follow similar dynamics and are competing outcomes of the ion–electron interaction. A simple picture of the recombination process of D5+ which captures the essential physics is suggested.