O3 full photo-fragmentation TALIF spectroscopy for quantitative diagnostics of non-thermal O2-mixed plasmas

In this study, we explore the potential of using laser-induced photo-fragmentation of O-3 by UV radiation as a quantitative diagnostic tool in non-thermal O-2-mixed plasmas. We analyze the optical processes of O-3 using a comprehensive kinetic model with a 226 nm laser, which is typically used in the two-photon absorption laser-induced fluorescence (TALIF) measurement of O atoms. Our model demonstrates that the fluorescence intensity from atomic O fragments produced by the same laser is directly proportional to the population of precursor O-3. This makes various diagnostic purposes achievable through the proposed O-3 full photo-fragmentation (FPF) TALIF spectroscopy, including calibration of TALIF signals of O atoms and quantification of both O and O-3 in O-2-mixed plasmas. We present detailed theoretical principles, technical requirements, and successful examples of implementation for different diagnostic aims using the proposed O-3 FPF-TALIF spectroscopy. However, we also specify the limitations of the developed diagnostic methods, particularly under low E/N conditions (<30 Td), where other interferential species such as the vibrationally excited ground-state O (2) ( X (3) S- (g) , v ?0 ) are abundantly produced.

Automated summary

In this study, we investigate the potential of using laser-induced photo-fragmentation of O-3 by UV radiation for quantitative diagnostics in non-thermal O-2-mixed plasmas. By analyzing the optical processes of O-3 using a comprehensive kinetic model with a 226 nm laser, we demonstrate that the fluorescence intensity from atomic O fragments is directly proportional to the population of precursor O-3. This allows for various diagnostic purposes, such as calibration of O atom signals and quantification of O and O-3 in O-2-mixed plasmas, using the proposed O-3 full photo-fragmentation (FPF) TALIF spectroscopy.