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Updated: Jun 22, 2026

Non-equilibrium Microwave Plasma for Efficient High Temperature Chemistry
Published on: August 1, 2017
Measurement of molecular rotational temperature in a supersonic gas jet with high-order harmonic generation
Kazumichi Yoshii1, Godai Miyaji, Kenzo Miyazaki
1Advanced Laser Science Research Section, Institute of Advanced Energy, Kyoto University, Kyoto 611-0011, Japan.
Abstract:
We apply high-order harmonic generation to sensitive measurements of the molecular rotational temperature in a thin supersonic gas beam. The method uses nonresonant pump and probe femtosecond laser pulses to generate harmonic radiation from coherently rotating molecules. The rotational temperature of molecules can be derived accurately with high spatial and temporal resolutions from the Fourier spectrum of time-dependent signals. The validity of this method was tested for an expanding flow of an N(2) beam with a rapid temperature decrease. The results show the versatile applicability of this method.
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