Mass–yield distributions of fission products from photo-fission of natPb induced by 50–70 MeV bremsstrahlung

Calculation of the fission-fragment yields of the pre-actinide nuclei by the example of the Pbnat isotopes

“…The same reason is crucial at pre-actinide of the mass/charge fission fragments spectra for other pre-actinide fission nuclei, as Ta, Re, In, Au and Hg. The experimental results of nat Pb photofission confirmed the single-humped form of nuclear fission-fragment yields distribution, and there is a tendency of peak expanding of gamma-quantum energy: from 60 MeV to 2.5 GeV [4,5]. Anisotropy, particularly, double-hamped form of nat Pb isotopes fission-fragment yields was not observed in this experiment and the cause is to be sought in the conditions of experiment.…”

“…For example, in case of 208 Pb isotope the fission fragments mass spectrum shape can vary from doublehumped (Figure 1), when during the experiment we can observe long-and shortlived fission fragments, that are possible at m t  1 sec; to the single-humped one, when m t   1 hour and long-lived nuclei fragments are fixed only. Last case meets the experimental conditions [4] and its results could be explained by the dynamics of nuclear reactions. Thus, the isotopes 103,105 Ru had been experimentally observed in maximum of fission fragments yields for 208 Pb [4,5], could appear as result of the transformations chains: the long-living isotopes of Zr are formed, which was observed in [4].…”

“…Last case meets the experimental conditions [4] and its results could be explained by the dynamics of nuclear reactions. Thus, the isotopes 103,105 Ru had been experimentally observed in maximum of fission fragments yields for 208 Pb [4,5], could appear as result of the transformations chains: the long-living isotopes of Zr are formed, which was observed in [4]. The results of such isotopic transformations are schematically illustrated in Fig.…”

“…On the other hand, data of nuclei fission are important for understanding the stability of atomic nuclei and the nature of nuclear forces. Although the data on the mass or charge fission-fragment yields of that nuclei currently are very limited, the existing experiments of nuclei fission, stimulated by the interaction with charged particles [1][2][3] or bremmstrahlung radiation [4,5] for a wide energy range 50 MeV -2 5 GeV should be emphasized. Theoretical studies of the peculiarities of energetic structure and medium heavy nuclei fission are significantly limited and concerns to the calculation of transient configurations and statistical characteristics of pre-actinide nuclei in the fission reactions, see [6,7].…”

Investigation of ^natPb photofission

“…рис.1) это свидетельствует об высоких значениях фотовозбуждения nat Pb и превалировании симметричных компонент осколков деления. Отметим, что эта же тенденция наблюдалась другими авторами (см., например, [11]).…”