Novel Ultrasensitive Instrumentation for Trace Gas Measurements in the Field

72855S03-I The understanding of atmospheric chemistry and pollution transport in the troposphere, on large and small spatial scales, is limited by the availability of reliable, sensitive, and accurate instrumentation that is easy to use and yields rapid, real-time results. This project will develop a novel, compact, and rugged instrument that sensitively and accurately measures the concentrations of important atmospheric trace gases (NO, NO2, NO3, N2O, CO) and the fluxes of N2O and CO. The instrument, based on a novel technology called Off-Axis Integrated Cavity Output Spectroscopy (ICOS) and on state-of-the-art diode lasers and quantum-cascade lasers, will be easy to use and will provide real-time measurements in the field and on board aircraft. Phase I will design, build, and test an Off-Axis ICOS instrument for measurements of the target species (NO2, NO3, N2O5, CO, N2O), based on absorption in the visible and infrared regions using two diode lasers and a quantum cascade laser. Measurements will be performed on calibrated gas mixtures to determine the accuracy, precision, and sensitivity of the instrument. Lastly, a Phase II instrument will be designed, and the costs of building and selling instruments in small and large quantities will be estimated. Commercial Applications and Other Benefits as described by awardee: The instrumentation should find application in atmospheric studies, medical diagnostics to detect common diseases, and the monitoring and control of several industrial processes.