Two-Photon Absorption Laser Induced Fluorescence of Atomic Nitrogen by an Alternative Excitation Scheme
نویسندگان
چکیده
A two-photon absorption laser induced fluorescence (TALIF) scheme to monitor ground state atomic nitrogen is described. Excitation at 207 nm to the (3p) S3/2 upper state is demonstrated to be superior to the traditional 211 nm excitation to (3p) D7/2 . Most striking is the low quenching rate of the upper (3p) S3/2 state by N2 at kq = 6.7(9)x10 −11 cm3/s, nearly an order of magnitude lower than the traditional technique. The two-photon excitation rate at 207 nm is also measured to be a factor of 3.5 greater than the traditional scheme. The results suggest that the 207 nm excitation scheme should be employed in future N-atom diagnostic work. ∗Work was performed at Air Force Research Laboratory, Wright Patterson AFB, OH
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