RADIO FREQUENCY SYNCHROTRON RADIATION FROM ELECTRONS TRAPPED IN THE EARTH'S MAGNETIC FIELD.

It is well known that high energy electrons spiraling along magnetic field lines radiate appreciable power at radio frequencies via the synchrotron process. Hence, electrons trapped in the earths magnetic field are a possible source of radio noise. Indeed, electrons injected by high altitude nuclear tests resulted in HF and VHF radio noise observed by ground-based receivers. The strength of this noise was analyzed by Peterson and Hower 1964 in terms of a synchrotron model. The basic problem analyzed in the present study is the nature of the radio frequency synchrotron noise, due to electrons in the natural Van Allen belts, that could be observed by a high altitude earth satellite. This problem is considered in terms of radiative transfer, i.e., the transfer of electromagnetic energy from the radiating electrons along a ray path that terminates at the satellite receiver. Estimates of satellite-observed synchrotron emission are made by applying the appropriate solution of the radiative transfer equation to a magnetospheric plasma model based on satellite- and ground-based measurements.