Registration Number
0222U001013,
0121U112015
, R & D reports
Title
Spectroscopy of positron lifetime in structural materials of atomics
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Head
Lebed Oleksandr A., Доктор фізико-математичних наук
Registration Date
23-01-2022
Organization
Institute of Applied Physics National Academy of Sciences of Ukraine
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Analytical approaches are considered for calculating the positron lifetime in the construction materials of nuclear reactors taking into account local changes in electron density associated with its defective structure. The Tao-Eldrup model has been developed, which allows to analytically calculate the positron lifetime in a spherically symmetric potential well. The new model allows to take into account the tunneling of the positron from a point defect in the base material. It is shown that with increasing the height of the potential well, the positron lifetime value increases quite rapidly and can be two orders of magnitude higher than the positron lifetime in the material bulk. The development of efficient and flexible algorithms for modeling the positron annihilation process and determining its lifetime in reactor construction materials based on the density functional theory within the ABINIT software package has been started. The ABINIT software package was tested and studied in terms of positron lifetime spectrometry. It is shown that the model is quite well constructed for semiconductor materials. For example, for silicon, the lifetime of positrons, both in the presence of defects and in their absence, shows good agreement with the results of other authors.
Product Description
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Vorona Maryna I.
Krukla Sergey V.
Ovcharenko Artur Yu.
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2022-03-09
