Dr. Adams will use the laboratory technique of flowing afterglow to create electron-ion plasmas of those ions which take part in the synthesis of interstellar molecules. Plasmas of sufficient density can be created to ensure that these ions rapidly recombine by dissociative electron-ion recombination before they can undergo further ion-neutral reactions. The rate coefficients for the recombinations will be determined using a Langmuir probe for cases where the data are not available in the literature. The neutral products will be identified and their contribution to the product distribution will be determined using the spectroscopic techniques of laser induced fluorescence, resonance enhanced multi-photon ionization, vacuum ultraviolet absorption spectroscopy, and emission spectroscopy. The data that Dr. Adams will obtain are critical for establishing the ion-chemical routes for molecular synthesis in interstellar gas clouds. With these data, the available theoretical models for molecular synthesis can be used with confidence, an essential requirement if the astronomical observations of molecular emissions and absorptions are to be used to deduce many of the fundamental properties of the molecular clouds. The rate data are also necessary for determining the viability of the current theories of the recombination process.
