A measurement of the effective recombination coefficient in the lower ionosphere

Utilizing the charged-particle spectra obtained on a recent Nike-Tomahawk firing, the production of electrons in the lower ionosphere was calculated. On the same rocket a Faraday rotation experiment measured the electron concentration. The ratio of the electron production to the square of the electron concentration is the effective recombination coefficient, αeff. The results obtained through this technique give a value for αeff of approximately 6 × 10−7 cm³/sec at 65 kilometers. This value is in reasonable agreement with that cited by other authors. Closer agreement is achieved when recent experimental values of the negative ion ratio are substituted in the earlier work.