Dissociative recombination and excitation of H-3(+)

Using the ASTRID heavy-ion storage ring, absolute cross sections for dissociative recombination and dissociative excitation of vibrationally cold H-3(+) have been measured as a function of energy in the region E=0-34 eV. A thermal rate coefficient for dissociative recombination of (1.0 +/- 0.2) x 10(-7) cm(3) s(-1) at 300 K was obtained from cross sections at low energy. At high energy, capture into a group of doubly excited states of H-3 gives rise to resonances in the dissociative recombination as well as in the dissociative excitation cross sections.