Surface Science Studies of the Non-Thermal Processing of Model Astrophysical Ices

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This project will use experimental surface science studies to investigate the non-thermal processing (by electrons and photons) of model astrophysical ices in conditions relevant to interstellar space and to cometary and planetary ices. This research is particularly timely because of the upcoming launch of the James Webb Space Telescope (JWST), which will allow the detection of molecules in space with much higher sensitivity than previously possible. The student will use low energy electrons or ultra-violet light to irradiate ices and will then use surface science techniques such as temperature programmed desorption and surface infrared spectroscopy to monitor the products of the irradiation. The student will also use a newly developed, novel, reflection-absorption UV-visible spectrometer to measure the refractive index for model astrophysical ices in situ under conditions relevant to various astrophysical environments. These processes will be investigated on various model dust grain surfaces including carbonaceous and silicaceous dust grain analogues to further investigate the role of the grain surface in the observed Chemistry.The specific objectives of the work to be undertaken during this project are:- To undertake experimental investigations of the non-thermal processing of model astrophysical ices by ultra-violet radiation and low energy electrons.- To undertake experimental studies of the refractive index of model astrophysical ices using reflection-absorption UV-visible spectroscopy- To use data from the experiments to develop models that describe non-thermal desorption under astrophysical conditions