ANGULAR DISTRIBUTIONS AND ENERGY SPECTRA OF ELECTRONS ASSOCIATED WITH AURORAL EVENTS

Abstract

A number of Black Brant II rockets containing various charged-particle detectors have been fired during 1963 and 1964 from Fort Churchill, Manitoba. Most of the firings took place at times of auroral events and the rocket instrumentation was designed to study the particles associated with these events.Pitch-angle distributions have been observed for electrons with energies greater than 40 keV, which show varying degrees of isotropy in the pitch-angle range 0° to 90°. In no case has a distribution been observed in which the intensity increased towards small angles. In some cases electron-intensity changes appear to be correlated with changes in spectrum and angular distribution, while in other cases changes in these quantities do not appear to be related.The particle intensity measurements are used along with radio-frequency probe measurements of electron density to infer values for the nighttime recombination coefficient in the D region of the ionosphere.