Spectrally-quantified chemical reactivity of optical fluids and materials in the GMACS spectrograph for GMT
We present a preview of compatibility tests for index-matching fluids with commonly used optical assembly materials. Although we focus on fluid candidates for GMACS, the results of the conducted experiments are applicable to all instruments that use optical index-matching fluids. The experiment presented here aims to identify potentially corrosive matchings of fluids and materials. In the experiment, a material (RTV, polyethylene, delrin, etc.) is submerged in a quartz cuvette of fluid (Cargille liquids, glycerin, etc.). Contamination is observed by using a spectrometer to measure the absorption spectrum at various post-submersion times. The current results have large measurement errors compared to the signal, and no contamination appears to have taken place. We detail the source of these errors and make suggestions for similar future experiments.