Among the most fundamental questions in astronomy are those concerning the formation of stars and planets from interstellar material and the feedback mechanism from stars on the dynamics and chemical evolution of ISM itself. Recently, observations at radio, millimeter and sub-mm molecular-line wavelengths provide crucial insights into almost all phases of the ISM, from overall galactic evolution to the composition of planetary atmospheres and hence the possible development of life forms on Earth-like planets. Molecules are present in all these environments, proving extremely useful tracers of the structures of circumstellar shell, planetary nebulae, dense and diffuse clouds, cloud cores, and protostellar disks. Because of their unique connection to this wide range of astrochemical objects, obtaining a clear understanding of the chemistry of interstellar molecules is essential to evaluating the life cycles of the ISM and its relationship to planet solar system formation.
Although astrochemical observations continue to lead to detection of unexpected molecules, however, they are relatively decoupled from laboratory spectroscopic and chemical dynamic studies which enable formulation of realistic predictive models of the evaluation of interstellar chemistry in astrochemical relevant objects.
We here present new results for some astrochemically relevant reaction processes obtained using reflectron velocity map ion imaging and Megapixel ion imaging techniques developed in laboratory recently. Using reflectron multimass velocity map ion imaging, we studied the vibrationally mediated photodissociation dynamics in the ethylene cation, and the conformer selective photoionization and photodissociation dynamics in propanal cation from the well defined quantum states. The experimental results show strongly coupled angular and translational energy distributions revealing features of the reaction not seen in previous studies. These observations provide new fundamental insights into the dynamics of the astrochemical reactions.