Free radicals in exoplanet atmosheres: their production, detection and spectroscopic characterization in laboratory

In the proposed research within the framework of the helping grant we will focus on one aspect of this unsuccessful GACR project. Specifically, to develop experimental methodology for laboratory in-situ synthesis of molecular free radicals in our supersonic jet source and to integrate this radical source with existing high sensitivity spectroscopic techniques to characterize the produced transient molecules with high resolution molecular spectroscopy. We plan to modify existing supersonic jet molecular source (currently used for spectroscopic studies of cold stable molecules) to be coupled with electric discharge in the pre-expansion region of the molecular flow. Free radicals produced in the discharge will be subsequently cooled in the supersonic expansion leading to significant simplification of observed molecular spectra. This technique has been already used in our laboratory in the past (as well as others), yet number of improvements are planed to make the setup more reliable and efficient. In particular we would like to implement modulation of the discharge to discriminate between stable species in the gas flow and free radicals produced in the discharge.