Dissociation dynamics in the dissociative electron attachment to ammonia molecule.

Complete dissociation dynamics of low energy electron attachment to ammonia molecule has been studied using velocity slice imaging (VSI) spectrometer. One low energy resonant peak around 5.5 eV and a broad resonance around 10.5 eV incident electron energy has been observed. The resonant states mainly dissociate via H$^-$ and NH$_2^-$ fragments, though for the upper resonant state, signature of NH$^-$ fragments are also predicted due to three body dissociation process. Kinetic energy and angular distributions of the NH$_2^-$ fragment anions are measured simultaneously using VSI technique. Based on our experimental observations, we find the signature of A$_1$ symmetry in the 10.5 eV resonance energy whereas, the 5.5 eV resonance is associated with the well known A$_1$ symmetry.