The fragment angular distributions of fusion-fission reactions for the systemsof <sup>16</sup>O+<sup>232</sup>Th,<sup>19</sup>F+<sup>232</sup>Th and <sup>16</su...The fragment angular distributions of fusion-fission reactions for the systemsof <sup>16</sup>O+<sup>232</sup>Th,<sup>19</sup>F+<sup>232</sup>Th and <sup>16</sup>O+<sup>238</sup>U at near-and sub-barrier energies were measured.The measured fragment anisotropies obviously deviate from the predictions ofscission-point transition-state model.We also compared the excitation energy of tiltingmode with the statistical assumption.It was found that thermal equilibrium is not estab-lished at scission for the reactions studied.展开更多
Exploiting the concept of the dinuclear system,the interaction potential energy of two fragments that are quite close to each other is analyzed.A semi-classical method is used to calculate fission fragment yields usin...Exploiting the concept of the dinuclear system,the interaction potential energy of two fragments that are quite close to each other is analyzed.A semi-classical method is used to calculate fission fragment yields using a simplified two-dimensional scission-point model.By considering the tip-to-tip orientation at the scission point of the fission process,we investigate the mass,charge,and kinetic-energy distributions of the fission fragments,for excitation energies in the 0-20 MeV range.Our results show that the fission fragment distributions are reproduced quite well,including the recent experimental results for the isotone chain[D Ramos et al.Phys.Rev.C 97,054612(2018)].Thus,the simplified model is useful for multi-parameter global measurements of fission products.展开更多
The scission point model is improved by considering the excitation-dependent liquid drop model to calculate mass distributions for neutron-induced actinide nuclei fission.Excitation energy effects influence the deform...The scission point model is improved by considering the excitation-dependent liquid drop model to calculate mass distributions for neutron-induced actinide nuclei fission.Excitation energy effects influence the deformations of light and heavy fragments.The improved scission point model shows a significant advance with regard to accuracy for calculating pre-neutron-emission mass distributions of neutron-induced typical actinide fission with incident-neutron-energies up to 99.5 MeV.The theoretical frame assures that the improved scission point model is suitable for evaluating the fission fragment mass distributions,which will provide guidance for studying fission physics and designing nuclear fission engineering and nuclear transmutation systems.展开更多
基金The project supported by the National Natural Science Foundation of China under the contract No.19275067.
文摘The fragment angular distributions of fusion-fission reactions for the systemsof <sup>16</sup>O+<sup>232</sup>Th,<sup>19</sup>F+<sup>232</sup>Th and <sup>16</sup>O+<sup>238</sup>U at near-and sub-barrier energies were measured.The measured fragment anisotropies obviously deviate from the predictions ofscission-point transition-state model.We also compared the excitation energy of tiltingmode with the statistical assumption.It was found that thermal equilibrium is not estab-lished at scission for the reactions studied.
基金Supported by National Natural Science Foundation of China(11875301,U1832167)。
文摘Exploiting the concept of the dinuclear system,the interaction potential energy of two fragments that are quite close to each other is analyzed.A semi-classical method is used to calculate fission fragment yields using a simplified two-dimensional scission-point model.By considering the tip-to-tip orientation at the scission point of the fission process,we investigate the mass,charge,and kinetic-energy distributions of the fission fragments,for excitation energies in the 0-20 MeV range.Our results show that the fission fragment distributions are reproduced quite well,including the recent experimental results for the isotone chain[D Ramos et al.Phys.Rev.C 97,054612(2018)].Thus,the simplified model is useful for multi-parameter global measurements of fission products.
基金the NSFC-Nuclear Technology Innovation Joint Fund(U1867213)the NSAF(U1830102)+1 种基金the National Natural Science Foundations of China(12075105,11705071,11875155)the Fundamental Research Funds for the Central Universities(lzujbky-2021-kb09)。
文摘The scission point model is improved by considering the excitation-dependent liquid drop model to calculate mass distributions for neutron-induced actinide nuclei fission.Excitation energy effects influence the deformations of light and heavy fragments.The improved scission point model shows a significant advance with regard to accuracy for calculating pre-neutron-emission mass distributions of neutron-induced typical actinide fission with incident-neutron-energies up to 99.5 MeV.The theoretical frame assures that the improved scission point model is suitable for evaluating the fission fragment mass distributions,which will provide guidance for studying fission physics and designing nuclear fission engineering and nuclear transmutation systems.
