MEASUREMENT OF THE ANGULAR CORRELATION OF PROMPT γ-QUANTA AND NEUTRONS IN THE FISSION OF 235U ISOTOPE WITH HOT NEUTRONS

Abstract

To study the dynamics of the fission process, it is important to study the rotation (ROT) effect in the fission of different heavy nuclei with neutrons of different energies. Although these effects were initially detected in a series of experiments in ternary fission processes and measured for a number of nuclei, they are also observed in binary fission processes that occur by emission of γ-rays and neutrons. Unlike alpha particles, γ -rays and neutrons are uncharged, allowing us to better study the effects. The ROT effect on the angular distribution of fast γ-rays for binary fission of 233U has different signs in comparison to the analogous effect of 235U isotope binary fission, while for α particles the sign of the ROT effect is the same for the same nuclei. These discrepancies indicate that the results of existing measurements are not accurate enough or the proposed models for the ROT effect cannot be overall described, and there is another mechanism that better describes the effect for different distribution systems. Therefore, it is important to study the dependence of the ROT effect on the energy of the neutrons that cause fission. Therefore, the ROT effect was measured in the binary fission of the 235U isotope induced by 60 meV polarized monochromatic neutrons.