Excited states of ^(206)Rn have been examined via the 197 Au(^(14)N,5n)^(206)Rn fusion reaction at a beam energy of 78 MeV.A number of transitions and levels are identified by the γ-γ coincidence measurement,further...Excited states of ^(206)Rn have been examined via the 197 Au(^(14)N,5n)^(206)Rn fusion reaction at a beam energy of 78 MeV.A number of transitions and levels are identified by the γ-γ coincidence measurement,further enriching the level scheme of ^(206)Rn.The fullconfiguration shell model and nucleon-pair approximation(NPA)were utilized to investigate the single-particle configurations and seniority structures in ^(206)Rn.The results of these two calculations suggest that 2_(1)^(+) and 4_(1)^(+) states exhibit only a 50%component of a seniority-two state associated with a broken neutron pair.The collectivity of these two states primarily arises from configuration mixing due to residual proton-neutron interactions.Furthermore,6_(1)^(+) and 8_(1)^(+) states are predominantly characterized by a seniority-two state marked by a broken proton pair.展开更多
In this paper,we study the systematics of the 2_(1)^(+)states in the N=82 even-even isotones with proton numbers between 52 and 72.We calculate the level energies of the 0_(1)^(+),2_(1)^(+)states and the electric quad...In this paper,we study the systematics of the 2_(1)^(+)states in the N=82 even-even isotones with proton numbers between 52 and 72.We calculate the level energies of the 0_(1)^(+),2_(1)^(+)states and the electric quadrupole reduced transition probabilities B(E2;2_(1)^(+)→0_(1)^(+)),in the framework of the nuclear shell model with a monopole-and multipole-optimized realistic interaction.Our calculations yield good agreement with the experimental data and show a 2.5 MeV gap at Z=64 subshell closure in^(146)Gd.We predict that the B(E2;2_(1)^(+)→0_(1)^(+))value for^(146)Gd is close to those for^(142)Nd and^(144)Sm,and the values increase rapidly from^(148)Dy to^(152)Yb.展开更多
Excited states of odd-odd nucleus 92Nb and odd-A nucleus 93Nb were populated in the 6 Li+ 89 Y reaction with an incident energy of 34 MeV. The processes that produce 92,93Nb and can be measured by a combination of lig...Excited states of odd-odd nucleus 92Nb and odd-A nucleus 93Nb were populated in the 6 Li+ 89 Y reaction with an incident energy of 34 MeV. The processes that produce 92,93Nb and can be measured by a combination of light charged particle and gamma ray measurements are discussed. Twenty new transitions are observed and eight new levels are constructed in 92Nb, and in addition two new transitions are added to the level scheme of 93Nb. Using shell2 model calculations, the low-lying structure of 9 Nb is investigated and compared with the experimental results.展开更多
In this paper,we study the symmetry energy and the Wigner energy in the binding energy formula for atomic nuclei.We simultaneously extract the I2 symmetry energy and Wigner energy coefficients using the double differe...In this paper,we study the symmetry energy and the Wigner energy in the binding energy formula for atomic nuclei.We simultaneously extract the I2 symmetry energy and Wigner energy coefficients using the double difference of "experimental" symmetry-Wigner energies,based on the binding energy data of nuclei with A≥16.Our study of the triple difference formula and the "experimental" symmetry-Wigner energy suggests that the macroscopic isospin dependence of binding energies is explained well by the I2 symmetry energy and the Wigner energy,and further consideration of the I4 term in the binding energy formula does not substantially improve the calculation result.展开更多
基金Supported partially by the National Natural Science Foundation of China (10975191,U1867210,11375023,11475014,11575018,12075169,12322506)the National Key R&D program of China (2016YFA0400504)。
文摘Excited states of ^(206)Rn have been examined via the 197 Au(^(14)N,5n)^(206)Rn fusion reaction at a beam energy of 78 MeV.A number of transitions and levels are identified by the γ-γ coincidence measurement,further enriching the level scheme of ^(206)Rn.The fullconfiguration shell model and nucleon-pair approximation(NPA)were utilized to investigate the single-particle configurations and seniority structures in ^(206)Rn.The results of these two calculations suggest that 2_(1)^(+) and 4_(1)^(+) states exhibit only a 50%component of a seniority-two state associated with a broken neutron pair.The collectivity of these two states primarily arises from configuration mixing due to residual proton-neutron interactions.Furthermore,6_(1)^(+) and 8_(1)^(+) states are predominantly characterized by a seniority-two state marked by a broken proton pair.
基金National Key R&D Program of China(2018YFA0404403)National Natural Science Foundation of China(12075169,12035011,11605122)Fundamental Research Funds for the Central Universities(22120240207)。
文摘In this paper,we study the systematics of the 2_(1)^(+)states in the N=82 even-even isotones with proton numbers between 52 and 72.We calculate the level energies of the 0_(1)^(+),2_(1)^(+)states and the electric quadrupole reduced transition probabilities B(E2;2_(1)^(+)→0_(1)^(+)),in the framework of the nuclear shell model with a monopole-and multipole-optimized realistic interaction.Our calculations yield good agreement with the experimental data and show a 2.5 MeV gap at Z=64 subshell closure in^(146)Gd.We predict that the B(E2;2_(1)^(+)→0_(1)^(+))value for^(146)Gd is close to those for^(142)Nd and^(144)Sm,and the values increase rapidly from^(148)Dy to^(152)Yb.
基金Supported by National Natural Science Foundation of China(U1867210,11775098,11475013,U1832130 and 11775316)
文摘Excited states of odd-odd nucleus 92Nb and odd-A nucleus 93Nb were populated in the 6 Li+ 89 Y reaction with an incident energy of 34 MeV. The processes that produce 92,93Nb and can be measured by a combination of light charged particle and gamma ray measurements are discussed. Twenty new transitions are observed and eight new levels are constructed in 92Nb, and in addition two new transitions are added to the level scheme of 93Nb. Using shell2 model calculations, the low-lying structure of 9 Nb is investigated and compared with the experimental results.
基金Supported by the National Key R&D Program of China(2018YFA0404403)the National Natural Science Foundation of China(12075169,11605122,11875188)。
文摘In this paper,we study the symmetry energy and the Wigner energy in the binding energy formula for atomic nuclei.We simultaneously extract the I2 symmetry energy and Wigner energy coefficients using the double difference of "experimental" symmetry-Wigner energies,based on the binding energy data of nuclei with A≥16.Our study of the triple difference formula and the "experimental" symmetry-Wigner energy suggests that the macroscopic isospin dependence of binding energies is explained well by the I2 symmetry energy and the Wigner energy,and further consideration of the I4 term in the binding energy formula does not substantially improve the calculation result.