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Information × Registration Number 0217U001185, 0112U005132 , R & D reports Title Investigation of fission dynamic of radioactive transuranium nuclei at excitation energies of compaund nuclei near 10-12 МeV. popup.stage_title Head Zheltonozhsky Victor Aleksandrovich, Доктор фізико-математичних наук Registration Date 26-01-2017 Organization Institute For Nuclear Research Of National Academy Of Sciences Of Ukraine popup.description2 The isomeric yields ratios of 235U, 237Np and 239Pu photofission products have been measured after irradiation of the targets by bremmsstrahlung photons with Ebr = 18 MeV. New data were obtained on yields of isomeric pairs of 84Br, 90Rb, 131Te, 132Sb, 132I, 133Te, 134I, 135Xe nuclei. The average angular momentum of the investigated fission fragments were defined in the framework of the generalized statistical model of decay using EMPIRE 3.2. code. In general, it is possible to draw a conclusion that the average angular moments of the heavy fission fragments are about 3 times higher, than the average angular moments of the light fission fragments and its values considerably differ from values of the angular moments of the fissionable nuclei. This circumstance demonstrates existence of the additional mechanism of the formation of angular momentum in heavy fragments. The regular exception is 135Xe nuclei for which the average angular moments both in reaction (g, f), and in reactions (g, f) + (g, nf) make values order 1.5h. One of the possible reasons of such low values can be the fact that light fragments of fission together with 135Xe are Sr, Y, Zr isotopes with the considerable excess of neutrons which can be strongly deformed. It can result in great values of the average angular moments in these light fragments, and then the execution of a conservation law of the complete angular momentum of system will result in decrease of the 135Xe average angular momentum. The additional contribution of the symmetric fission channel or a possibility of the significant increasing of contribution of prefissioning neutrons can be other possible causes. In this case it is always possible to combine eject of neutrons at the corresponding deformation from subshells with the larger or smaller angular moments. Product Description popup.authors Є.П. Ровенських І.М. Вишневський А.М. Саврасов В.О. Желтонoжський В.П. Хоменков popup.nrat_date 2020-04-02 Close