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arXiv · 2404.11909

Calibration of hydrogen atoms measurement using femtosecond two-photon laser induced fluorescence

Andrey Starikovskiy·Arthur Dogariu
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Abstract

A new calibration method for H-fs-TALIF is proposed, and the ratio of two-photon absorption cross-sections, $σ^{(2)}$, for atomic hydrogen (H) and krypton (Kr) is determined for the broadband emission of a femtosecond laser system. The estimated ratio of the two-photon absorption cross-sections for H and Kr is $σ^{(2)}$ for H and Kr $σ^{(2)}$(Kr)/$σ^{(2)}$(H) = $0.027\pm 20$%, which is nearly twenty times lower than values previously obtained with narrowband nanosecond lasers. This discrepancy highlights the need for independent calibration of TALIF measurements for a specific laser pulsewidth range.

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Andrey Starikovskiy, Arthur Dogariu. 2025-03-17. Calibration of hydrogen atoms measurement using femtosecond two-photon laser induced fluorescence. https://arxiv.org/abs/2404.11909

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