OBSERVED BARIUM EMISSION RATES

The barium releases from the CRRES satellite have provided an opportun ity for verifying theoretically calculated barium ion and neutral emis sion rates. Spectra of the five Caribbean releases in the summer of 19 91 were taken with a spectrograph on board a U.S. Air Force jet aircra ft. Because the line of sight release densities are not known, only re lative rates could be obtained. The observed relative rates agree well with the theoretically calculated rates and, together with other obse rvations, confirm the earlier detailed theoretical emission rates. The calculated emission rates can thus with good accuracy be used with ph otometric observations. It has been postulated that charge exchange be tween neutral barium and oxygen ions represents a significant source f or ionization. If so, it should be associated with emissions at 4957.1 5 angstrom and 5013.00 angstrom, but these emissions were not detected .