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Information × Registration Number 0222U001013, 0121U112015 , R & D reports Title Spectroscopy of positron lifetime in structural materials of atomics popup.stage_title Head Lebed Oleksandr A., Доктор фізико-математичних наук Registration Date 23-01-2022 Organization Institute of Applied Physics National Academy of Sciences of Ukraine popup.description2  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 popup.authors Vorona Maryna I. Krukla Sergey V. Ovcharenko Artur Yu. popup.nrat_date 2022-03-09 Close