INTERRUPTED NEUTRON-IRRADIATION EXPERIMENTS INVOLVING DISLOCATIONS IN SODIUM-CHLORIDE

Ultrasonic and electric charge experiments near room temperature yield information on dislocation pinning, damping, and charging during interruptions to high-energy neutron irradiation. Small changes in the pinning point density during interruption provide evidence for a dfifusion pinning process in the core region. Changes in the decrement are found to be not wholly dependent on the fourth power of the average loop length. Changes of 10-20% are found in the damping factor B during interruptions that depend only on the concentration of point defects in the regions surrounding the dislocations and not on the state of the core region. Experiments below room temperature indicate negligible changes in dislocation charge q during interruption. There is no evidence for any direct relationship between B and q.