Revisiting spontaneous Raman scattering for direct oxygen atom quantification

van de Steeg, A. W.; Vialetto, L.; Silva, A. F.; Peeters, F. J.; van den Bekerom, D. C. M.; Gatti, N.; Diomede, P.; van de Sanden, M. M.; van Rooij, G. J.

doi:10.1364/ol.424102

DOE OSTI · 1877143

Revisiting spontaneous Raman scattering for direct oxygen atom quantification

van de Steeg, A. W.·Vialetto, L.·Silva, A. F.·Peeters, F. J.·van den Bekerom, D. C. M.·Gatti, N.·Diomede, P.·van de Sanden, M. M.·van Rooij, G. J.

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Abstract

In this paper, the counterintuitive and largely unknown Raman activity of oxygen atoms is evaluated for its capacity to determine absolute densities in gases with significant O-density. The study involves C O 2 microwave plasma to generate a self-calibrating mixture and establish accurate cross sections for the 3 P 2 ↔ 3 P 1 and 3 P 2 ↔ 3 P 0 transitions. The approach requires conservation of stoichiometry, confirmed within experimental uncertainty by a 1D fluid model. The measurements yield σ J = 2 → 1 = 5.27 ± s y s : 0.53 r a n d : 0.17 × 10 - 31 c m 2 / s r and σ J = 2 → 0 = 2.11 ± s y s : 0.21 r a n d : 0.06 × 10 - 31 c m 2 / s r , and the detection limit is estimated to be 1 × 10 15 c m - 3 for systems without other scattering species.

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van de Steeg, A. W., Vialetto, L., Silva, A. F., Peeters, F. J., van den Bekerom, D. C. M., Gatti, N., Diomede, P., van de Sanden, M. M., van Rooij, G. J.. 2021-04-28. Revisiting spontaneous Raman scattering for direct oxygen atom quantification. https://doi.org/10.1364/ol.424102

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