SEARCH FOR E-REGION DISTURBANCES INDUCED BY ION CLOUD RELEASES AT F-REGION HEIGHTS

Theory indicates that following the release of an ion cloud at F-region heights, the electron density of the E-region is disturbed due to electron transfer between the cloud and its electrostatic image. Attempts to detect these disturbances experimentally from their associated optical emissions have however been rather inconclusive. By means of a sensitive radiowave technique, marked localized E-region disturbances have been detected following the release of ion clouds. The effect occurs for both barium and caesium clouds and is present at both temperate and high latitudes. The time of onset and the duration of the measured events is consistent with theoretical predictions for image-like disturbances. © 1978.