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Information × Registration Number 0223U000913, 0122U001483 , R & D reports Title Investigation of anomalous diffusion processes in the interaction of high-energy particles with intense external fields and matter popup.stage_title Head Onyshchenko Hennadii M., Кандидат фізико-математичних наук Registration Date 21-01-2023 Organization V.N. Karazin Kharkiv National University popup.description2  The analysis of the scattering process of fast charged particles in the crystal when the beam impinges on the crystal at a small angle to one of the crystallographic atomic planes was carried out. It is shown that when the beam impinges on the crystal at angles to the crystallographic planes of atoms close to the value of the critical angle of planar channeling for above-barrier particles, the phenomenon of anomalous diffusion takes place, which weakens the multiple incoherent scattering of particles in the crystal. This effect occurs for both positively and negatively charged particles. As the angle of incidence of particles on the crystal atomic planes increases, the diffusion index of particles in scattering approaches the corresponding value of the diffusion index in an amorphous medium. The effect of anomalous diffusion on the propagation of neutrons in the multiplying system was also studied. The classical equation of neutron diffusion does not allow to accurately take into account the presence of thin absorbing structures in a heterogeneous system. The presence of such structures leads to the occurrence of anomalous diffusion. The phenomenological approach of introducing fractional derivatives into the classical neutron diffusion equation was used, which describe the presence of anomalous diffusion in the system under consideration. The results of numerical calculations of the equations of anomalous neutron diffusion indicate that in the case of subdiffusion, which corresponds to the presence of thin absorbing elements in the system, there is an acceleration of the reduction of the neutron flux over time Product Description popup.authors Malovytsia Maksym S. Truten' Valentin I. Shus Oleksandr P. popup.nrat_date 2023-01-21 Close