反应HO_2+O→OH+O_2对OH夜气辉辐射的贡献

The contribution of reaction HO_2+O→OH+O_2 to OH nightglow

本文探讨了OH Meinel夜气辉辐射的光化学模式,给出OH(ν≤9)分子数密度分布的计算通式,重点研究了化学反应HO2+O→OH(ν≤6)+O2对ν≤6各振动能级上OH分子数密度分布以及(ν′—ν″)(ν′≤6)振动带气辉辐射的影响.结果表明,该反应对数密度的贡献随振动能级的减小而增大,对(ν′—ν″)振动带辐射的贡献随着较高振动能级ν′的减小而增大,以春分时为例,它可使第1振动能级上的OH分子最大数密度和(1—0)带的最大辐射率增加约33%,第6振动能级上的最大数密度和(6—ν″)带的最大辐射率增加约7%,(1—0)带的辐射强度增加约30%,(6—ν″)带的强度增加约11%.该反应使各振动能级上分子数密度的高度分布剖面以及各振动带体辐射率的高度分布剖面变宽,最大数密度、最大发射率所处的高度下降1km左右.此外,该反应的影响程度随着原子氧密度的降低而增大,随着温度的升高而增大,并且在夏至时最大,在冬至时最小.

The photochemical model for the OH Meinel bands nightglow emission is discussed. Both the expression for the number densities of OH （ v≤ 9） and the expression for the OH vibrational bands nightglow emission rates are derived from the photochemical model. The impact of chemical reaction, HO2 ＋ O→OH（ v ≤ 6） ＋ O2, on the number densities of OH（ v ≤6） and on the OH（v′-v″） （v′≤6） （v′ represent the higher vibrational levels and v″ represent the lower vibrational levels ） vibrational bands emission are studied detailedly. The results indicate that the contribution of the reaction to the number densities increases with decreasing v and the contribution to the OH（v′-v″） vibrational bands emission increases with decreasing v′. The calculations for vernal equinox, local midnight at （0°E, 45°N） show that the reaction makes the peak density for level v = 1 and the peak emission rate of the OH（1-0） vibrational band increase by about 33% , the peak density for level v = 6 and the peak emission rates of the OH（6-v″） vibrational bands increase by about7%, the OH（1-0） band intensity increase by about 30%, and the OH（6-v″） bands intensities increase by about 11%. Furthermore, the reaction can make the widths of the altitude profiles for both the number densities and the vibrational bands emission rates increase, and the peak altitudes of these profiles lower by about 1 km. The contribution of the reaction is sensitive to the atomic oxygen density and temperature. It increases with decreasing atomic oxygen density, and increases with increasing temperature almost linearly. And it is the strongest for summer solstice and the weakest for winter solstice.