One-neutron stripping process between^(6)Li and^(209)Bi was studied at 28,30,and 34 MeV using the in-beamγ-ray spectroscopy method.Theγ-γcoincident analysis clearly identified twoγ-rays feeding the ground and long...One-neutron stripping process between^(6)Li and^(209)Bi was studied at 28,30,and 34 MeV using the in-beamγ-ray spectroscopy method.Theγ-γcoincident analysis clearly identified twoγ-rays feeding the ground and long-lived isomeric states,which were employed to determine the cross section.The one-neutron stripping cross sections were similar to the cross sections of complete fusion in the^(6)Li+^(209)Bi system,but the one-neutron stripping cross sections decreased more gradually at the sub-barrier region.A coupled-reaction-channel calculation was performed to study the detailed reaction mechanism of the one-neutron stripping process in^(6)Li.The calculations indicated that the first excited state of 5 Li is critical in the actual one-neutron transfer mechanism,and the valence proton of 209Bi can be excited to the low-lying excited state in(^(6)Li,^(5)Li)reaction,unlike in the(d,p)reaction.展开更多
Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pair...Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.展开更多
为在γ放射性活度很大的测量中使测量系统得到更好的准确度，本文使用干扰源研究 HPGe探测器得到了测量系统死时间与计数损失的关系。在γ能量为0.3～1.3 M eV 时进行实验，使用10^4～10^5 Bq量级的放射源，修正能峰的计数率一般保持在...为在γ放射性活度很大的测量中使测量系统得到更好的准确度，本文使用干扰源研究 HPGe探测器得到了测量系统死时间与计数损失的关系。在γ能量为0.3～1.3 M eV 时进行实验，使用10^4～10^5 Bq量级的放射源，修正能峰的计数率一般保持在几十s－1，证明在误差范围（3％）内，计数损失随死时间变化的关系与射线能量和计数强度无关，任意强度的任意核素均可使用这一修正公式进行计数损失修正。展开更多
基金the National Nature Science Foundation of China(Nos.U2167204,11975040,and U1832130)the Brazilian funding agencies CAPES,CNPq,FAPERJ,and the INCT-FNA(Instituto Nacional de Ciência e Tecnologia-Física Nuclear e Aplicações)+5 种基金research project 464898/2014-5.S.P.Hu was supported by Guang dong Key Research And Development Program(No.2020B040420005)Guang dong Basic and Applied Basic Research Foundation(No.2021B1515120027)Ling Chuang Research Project of China National Nuclear Corporation(No.20221024000072F6-0002-7)Nuclear Energy Development and Research Project(No.HNKF202224(28))the‘111’center(B20065)the U.S.Department of Energy,Office of Science,Office of Nuclear Physics,under contract number DE-AC02-06CH1135.
文摘One-neutron stripping process between^(6)Li and^(209)Bi was studied at 28,30,and 34 MeV using the in-beamγ-ray spectroscopy method.Theγ-γcoincident analysis clearly identified twoγ-rays feeding the ground and long-lived isomeric states,which were employed to determine the cross section.The one-neutron stripping cross sections were similar to the cross sections of complete fusion in the^(6)Li+^(209)Bi system,but the one-neutron stripping cross sections decreased more gradually at the sub-barrier region.A coupled-reaction-channel calculation was performed to study the detailed reaction mechanism of the one-neutron stripping process in^(6)Li.The calculations indicated that the first excited state of 5 Li is critical in the actual one-neutron transfer mechanism,and the valence proton of 209Bi can be excited to the low-lying excited state in(^(6)Li,^(5)Li)reaction,unlike in the(d,p)reaction.
基金supported by the National Key R&D Program of China(No.2022YFA1602000)National Natural Science Foundation of China(Nos.12275081,U2067205,11790325,and U1732138)the Continuous-support Basic Scientific Research Project。
文摘Using the Skyrme density functional theory,potential energy surfaces of^(240)Pu with constraints on the axial quadrupole and octupole deformations(q_(20)and q_(30))were calculated.The volume-like and surface-like pairing forces,as well as a combination of these two forces,were used for the Hartree–Fock–Bogoliubov approximation.Variations in the least-energy fission path,fission barrier,pairing energy,total kinetic energy,scission line,and mass distribution of the fission fragments based on the different forms of the pairing forces were analyzed and discussed.The fission dynamics were studied based on the timedependent generator coordinate method plus the Gaussian overlap approximation.The results demonstrated a sensitivity of the mass and charge distributions of the fission fragments on the form of the pairing force.Based on the investigation of the neutron-induced fission of^(239)Pu,among the volume,mixed,and surface pairing forces,the mixed pairing force presented a good reproduction of the experimental data.
文摘为在γ放射性活度很大的测量中使测量系统得到更好的准确度，本文使用干扰源研究 HPGe探测器得到了测量系统死时间与计数损失的关系。在γ能量为0.3～1.3 M eV 时进行实验，使用10^4～10^5 Bq量级的放射源，修正能峰的计数率一般保持在几十s－1，证明在误差范围（3％）内，计数损失随死时间变化的关系与射线能量和计数强度无关，任意强度的任意核素均可使用这一修正公式进行计数损失修正。
