A comparison of high-altitude nuclear explosion effects in theElayer with variations in geomagnetic field strength

Abstract

A high-frequency ground-backscatter study conducted during the period of the July 9, 1962, high-altitude nuclear explosion over Johnston Island has yielded information which indicates that short-period fluctuations in E-layer ionization occurred o.ver the eastern United States within the first few seconds after the detonation. The onset time, periodic structure, and duration of the E-layer ionization disturbance have been found to bear a striking similarity to variations in the geomagnetic field measured by observers throughout the western hemisphere. The coincidence of geomagnetic field fluctuations and variations in E-layer ionization density is advanced as evidence that the perturbations were caused by neutrondecay • particles interacting with the magnetic field and the ionosphere. Res., 67 (12), 4929-4932, 1962. van Wijk, A.M., Magnetic effects of high-altitude bomb, J. Geophys. Res., 67(13), 5352, 1962. Wilson, C. R., and M. Sugiura, lgydromagnetic waves generated by the July 9, 1962, nuclear weapons test as observed at College, Alaska, J.