Study of Mass Spectrometric Ion Sampling Processes.
Final rept. 7 Apr 67-6 Jul 70,
AEROCHEM RESEARCH LABS INC PRINCETON N J
Pagination or Media Count:
Ion sampling experiments were undertaken to determine the nature and magnitude of the problems inherent in mass spectrometric rocket probing of the D region. Mass spectrometric techniques were used to analyze the positive and negative ions sampled with an inlet system with variable geometry. The basic sampling system is a conical probe designed to attach the shock, allowing direct and undisturbed sampling of ambient ions from the supersonic stream. Profiles of the ion composition can be taken in the supersonic gas stream ahead of the shock wave and through the subsonic gas stream behind the bow shock stationary shock layer technique. The ion sampling experiments have ascertained the effects of the shock and electric fields, which result in the fragmentation of cluster ions present in the supersonic stream and thereby alter the ion composition in the post-shock region. The decomposition kinetics of proton and NO3- hydrate ions HH2On and NO3-H2On were investigated and the rate constants for these decomposition reactions were determined. The importance of vibrational excitation in the decomposition reactions of hydrated protons was demonstrated. The present work indicates that the results from rocket-borne mass spectrometers are distorted by shock-induced and electric field-induced fragmentation. Author
- Atmospheric Physics
- Atomic and Molecular Physics and Spectroscopy