Updated Chemical, Radiative, and Transport Properties of Thermospheric Odd Nitrogen
Thursday, 18 December 2014: 9:25 AM
In the past decade many laboratory and quantum chemical results relevant to the chemical, transport, and radiative properties of thermospheric odd nitrogen have appeared. The impact of these updates on the odd nitrogen abundances, fluxes, and neutral temperature are assessed by inclusion into the Thermosphere-Ionosphere-Electrodynamics General Circulation Model (TIE-GCM) and comparison with data from the Student Nitric Oxide Explorer (SNOE) and Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) experiments. Regarding chemistry, electronically and vibrationally excited molecular nitrogen (N2(A)) has been found to be an important source of nitric oxide (NO) and electronically excited atomic nitrogen (N(2D)) [Campbell et al, 2007] while many key branching ratios and temperature dependences have been revised [Hellberg et al, 2003; Galvao et al, 2013]. The yields of vibrationally excited NO(v) from the N(2D)+O2 and N(4S)+O2 reactions have been determined [Miquel et al, 2003; Sultanov et al, 2006]; radiative cascade from NO(v) results in enhanced cooling near 5.3 μm which contributes roughly 20% of that due to collisions with hot atomic oxygen. Collision integrals for the He-NO and He-N(4S) interactions are known [Partridge et al, 2001; Haghighi et al, 2003] and the resulting transport coefficients are calculated and input to TIE-GCM v2.0, wherein He is treated as a major species.