Radiation damage fission fragment

Vance, E. R. Pillay, K. K. S. 1982. Fission fragment damage in crystalline phases possibly formed in solidified radioactive waste. Radiation Effects, 62, 25-38. 

Irradiation, as shown below, does not alter these characteristics in any appreciable way a few cases are cited that need to be singled out. This fact is especially important in the case of irradiation with fission fragments. Indeed, as shown below, the passage of these particles through solid matter produces structural modifications commonly known as radiations damage (24)- These have recently been investigated in the case of alumina, silica,... 

The study of radiation damage caused by fission fragments is of considerable practical interest. For this reason the problem has received closer attention than in the case of protons and alpha particles 48, 52-54). 

The effect of a high radiation flux upon the structure of metal phthalo-cyanines has been investigated. Intensities of 1020 thermal neutrons/cm2 tend to convert crystalline copper phthalocyanine to an amorphous state 806). Bowden and Chadderton 86, 36), using the electron microscope, have discussed the disorder in the molecular array caused by fission damage. Tracks and dislocations due to the passage of individual fission fragments could be seen. 

High energy particles not only cause ionization in the detector crystal but may displace some detector atoms from the crystal lattice. Radiation damage decreases with applied bias and increases with the particle mass. Such radiation damage to the crystals limits the lifetime of the detectors. The threshold dose (in particles/cm ) is about 10 for fission fragments, 10 for a, 10 for p, 10 for fast neutrons, and 10 for e . Radiation damage can usually be removed if the detector can be annealed at 200°C. 

Heavier particles, such as protons, a-particles, fast neutrons, and fission fragments, will usually transfer sufficient energy through elastic or inelastic collisions to remove nuclei from their lattice (crystalline) positions. This addition of vacancies and interstitial atoms causes property changes in metals. This effect of nuclear radiation is sometimes referred to as radiation damage. 

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