Research into Artificially Induced Atmospheric Disturbances.
Final rept. 6 May 93-19 Jun 96,
SPECTRAL SCIENCES INC BURLINGTON MA
Pagination or Media Count:
A detailed chemical kinetics model describing the interaction of an electron beam with the atmsophere is used to investigate N4S, N2D and N2P formation and the subsequent reaction of metastable N atoms with O2 on NO formation and emission during the EXCEDE III artificial auroral experiment. Of particular significance is the result that rotationally hot NO can be explained by the reaction of nonthermal N4S atoms with O2. The rate constants and vibrational distributions for rotationally hot NO are obtained from extensive quasiclassical trajectory calculations for N4SO2 reaction using realistic ab initio potential energy surfaces. This analysis provides the first quantitative evidence of the importance of hyperthermal N4S and N2D atoms in the formation of vibrationally and rotationally excited NO. Excellent agreement between the chemical kinetics model developed for EXCEDE and the NO vibrational populations derived from the interferometer data is obtained under conditions of thermalization of nitrogen atoms i.e., at 103 km under maximum dose conditions. Analysis of vibrational populations from the interferometer under other conditions indicate that hyperthermal N2D atoms may also pay an important role in NO formation or an additional mechanism for hot NO formation is necessary.
- Atmospheric Physics
- Physical Chemistry