10.25394/PGS.8970728.v1 Michael Thomas Arendt Michael Thomas Arendt Polarization Effects of Nitric Oxide Pure Rotational Transitions Demonstrated by Coherent Anti-Stokes Raman Scattering Purdue University Graduate School 2019 CARS Nitric Oxide Polarization CARS Pure Rotational CARS Coherent Anti-Stokes Raman Scattering Automotive Combustion and Fuel Engineering (incl. Alternative/Renewable Fuels) Mechanical Engineering Non-automotive Combustion and Fuel Engineering (incl. Alternative/Renewable Fuels) 2019-08-12 18:42:49 Thesis https://hammer.purdue.edu/articles/thesis/Polarization_Effects_of_Nitric_Oxide_Pure_Rotational_Transitions_Demonstrated_by_Coherent_Anti-Stokes_Raman_Scattering/8970728 Dual-broadband and dual-pump nanosecond CARS experiments were performed to investigate the pure rotational transitions of the nitric oxide molecule. The former experiment was initially utilized to determine the pure rotational structure while the latter focused on polarization suppression of the pure rotational transitions of nitric oxide. A polarization calculation and analysis were conducted on the rotational and vibrational transitions of nitrogen, and the pure rotational transitions of nitric oxide were subjected to a similar polarization scheme. The electronic transitions that arise due to the spin-split nature of nitric oxide ground electronic energy levels were suppressed by the polarization scheme in a similar manner to the rotational S branch transitions. Results have been compared with a spectral simulation developed by Dr. Lucht, and the theory is partially presented. Comparison between simulation and experimental data yielded favorable agreement for the pure rotational transitions of nitric oxide.