Chemistry calculations relating to AIM

This paper describes some single-cell rf-heating and air chemistry computations that are intended to model the conditions of an AIM experiment, either in a laboratory environment or in the atmosphere. For a pulsed mode of rf-induced ionization using repetitive 120-ns pulses with 1-ms separation we examine the relative amounts of power required to sustain ionization in the second and subsequent pulses compared to the first pulse. We also compare power requirements for sustained ionization at a pressure of 1 Torr (46 km altitude) and at 0.03 Torr (74 km altitude). The power needed in the 0.03-Torr case is substantially less than in the higher-pressure case. We find that at both pressures, using the rf power densities required to sustain ionization the neutral gas is heated very rapidly to temperatures exceeding 5000 K, leading to strong turbulence. We follow the chemical evolution of 55 species of atoms, molecules and ions, and we pay particular attention to the rate of production of N and NO, because of the effects of those species on the concentrations of stratospheric ozone. The N and NO production rates are not sufficient to cause serious concerns about ozone depletion. In the case representing 74 km altitude (Pmore » = 0.03 Torr) we find that quite high concentrations of NO will exist in the vicinity of the artificial ionization patch, leading to the possibility of enhanced local D-region ionization caused by the ionization of NO by solar Lyman-alpha. 30 figs.« less