High frequency electromagnetic radiation in CRRES geostationary injections

It is shown that experiments with geostationary injections of dense barium plasma clouds after CRRES program presented a unique opportunity for investigation of Earth's space environment radiation generation mechanism at frequencies 100 to1000 times higher than the usual plasma frequency signal. We present electromagnetic noise or radiostorm data obtained in Havana in broad frequency bands 45–90 MHz, 235MHz and 280 MHz after Ba injection. It is proposed that signals appearing with 7 to 10 min delay after injection possibly caused a substorm initiated by the injection, during which the radiation is generated by local energetic particles flowing through the irregular barium cloud. Another possibility is connected with irradiation of the barium cloud by the Jicamarca radar. Modulation of radioburst at barium gyrofrequency is typical for both cases.