Dependence of radiation damage on deviation from the bragg angle

A sensitive method of detecting radiation damage in metals, by electron microscope observation of the shrinking of small, faulted, vacancy loops produced by prior quenching, has been used to study displacement damage in electron-irradiated aluminium. It has been shown that the difference in damage rate between specimens oriented for anomalous transmission and absorption is sufficiently small to be accounted for on the basis of present theories. We would like to thank Dr. A. Howie who suggested the experiment to us, Dr. M. S. Spring for making his calculations available to us in advance of publication and Dr. L. M. Brown for a number of very valuable discussions. One of us (K. A. S.) would like to thank the British Council for providing financial support and the Pakistan Atomic Energy Commission for granting leave of absence.