Synchrotron radiation from high-energy electrons

This paper discusses the general characteristics of synchrotron radiation from high-energy electrons trapped in the earth's magnetic field and develops methods for calculating the radio noise that will be received at the ground. The synchrotron radiation from trapped electrons created by the nuclear explosion of July 9, 1962, is calculated. These calculations, based on electron flux density measurements in satellites, agree well with observations made at several radio frequencies in the 20–100 Mc/s frequency range at stations near the magnetic equator. It is concluded that the observed radio noise is generated primarily at heights above the magnetic equator between 1.2 and 1.6 earth radii and that it is a very insensitive measure of electrons moving at heights above about 1.6 earth radii because of the weak magnetic field at these heights.