Abstract

The reaction of chlorine with alkaline hydrogen peroxide has been used to produce O₂(<i>a</i>¹Δ_<i>g</i>) in a fast flow system at partial pressures up to about 0.5 Torr, and total pressures (mostly argon) in the range 0.8-2.5 Torr. Absolute concentrations of O₂(<i>a</i>¹Δ_<i>g</i>) were determined from the intensity of absorption of hydrogen emission lines in the vacuum-UV at 144.095 and 148.66 nm, for which the cross sections are known. The intensity of the O₂ (<i>a</i> → <i>X</i>) transition at 1270 nm, monitored simultaneously with a simple germanium detector, was found to vary linearly with [O₂(<i>a</i>¹Δ_<i>g</i>)], as expected. The germanium detector was calibrated at 1270 nm with a readily reproducible standard, the air afterglow continuum due to NO₂* at defined concentrations of O(³P) and NO. The ratio of <i>k</i>_<i>a</i> for O₂(<i>a</i>) <i>k</i>_→<i>a</i> O₂(<i>X</i>) + <i>hv</i>, to <i>k</i>_<i>c</i> for O + NO <i>k</i>_→<i>c</i> NO₂ + <i>hv</i>, is (1.4 ± 0.2) × 10⁻⁷ mol L⁻¹ at 1270 nm.

Measurement of the Raman cross section of O₂(a¹Δ_g)

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Rotational line strengths and self-pressure-broadening coefficients for the 1.27-μm, a¹Δ_g–X³Σ_g^-, v = 0–0 band of O₂

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Simulation and application of the emission line O₁₉P₁₈ of O₂(a¹Δ_g) dayglow near 1.27 μm for wind observations from limb-viewing satellites

Kuijun Wu, Di Fu, Yutao Feng, Juan Li, Xiongbo Hao, and Faquan Li
Opt. Express 26(13) 16984-16999 (2018)

Visible absorption bands of the (O₂)₂ collision complex at pressures below 760 Torr

Hans Naus and Wim Ubachs
Appl. Opt. 38(15) 3423-3428 (1999)

Direct measurement of O₂(a¹Δ) and O₂(X³Σ) in chemical oxygen–iodine lasers with use of spontaneous Raman imaging

V. Tom Gylys and Larry F. Rubin
Appl. Opt. 37(6) 1026-1031 (1998)