Open AccessQuantitative femtosecond, two-photon laser-induced fluorescence of atomic oxygen in high-pressure flames
Author(s) -
Kazi Arafat Rahman,
Venkat Athmanathan,
Mikhail N. Slipchenko,
Sukesh Roy,
James R. Gord,
Zhili Zhang,
Terrence R. Meyer
Publication year - 2019
Publication title -
applied optics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.668
H-Index - 197
eISSN - 2155-3165
pISSN - 1559-128X
DOI - 10.1364/ao.58.001984
Subject(s) - femtosecond , optics , laser induced fluorescence , fluorescence , materials science , laser , photon counting , photon , oxygen , atomic physics , physics , quantum mechanics
Quantitative femtosecond two-photon laser-induced fluorescence of atomic oxygen was demonstrated in an H 2 /air flame at pressures up to 10 atm. Femtosecond excitation at 226.1 nm was used to pump the 3pP3 J ' =0,1,2 ←←2pP3 J '' =0,1,2 electronic transition of atomic oxygen. Contributions from multiphoton de-excitation, production of atomic oxygen, and photolytic interferences were investigated and minimized by limiting the laser irradiance to ∼10 11 W/cm 2 . Quantitative agreement was achieved with the theoretical equilibrium mole fraction of atomic oxygen over a wide range of fuel-air ratios and pressures in an H 2 /air laminar calibration burner.