  We reported an imaging study of the dissociation dynamics of temporary
negative ion N2O- formed in the low-energy electron attachment, e- + N2O ->
N2O- -> N2 + O-. With the help of ab initio molecular dynamics calculations,
the evolution of momentum distributions of the O- fragment in terms of the
electron attachment energy is identified as the result of a competition between
two distinctly different indirect pathways, namely, climbing over and bypassing
the energy ridge after the molecular structure bending. These two pathways
prefer leaving the N2 fragment at the high vibrational and rotational states,
respectively.
