Based on the fully relativistic multiconfiguration Dirac-Hartree-Fock(MCDHF)method and the corresponding program package GRASP2018,a new program for calculating the polarizabilities is developed.As the first applicati...Based on the fully relativistic multiconfiguration Dirac-Hartree-Fock(MCDHF)method and the corresponding program package GRASP2018,a new program for calculating the polarizabilities is developed.As the first application,the static electric-dipole polarizabilities of the ground state 2s^(2)^(1)S_(0) and excited state 2s2p^(3)P_(0) of beryllium are calculated.By means of these polarizabilities,the blackbody radiation(BBR)shift of the 2s2p^(3)P_(0)→2s^(2)^(1)S_(0)clock transition is determined.The present results agree very well with other available theoretical results.展开更多
Atomic radiative data such as excitation energies, transition wavelengths, radiative rates, and level lifetimes with high precision are the essential parameters for the abundance analysis, simulation, and diagnostics ...Atomic radiative data such as excitation energies, transition wavelengths, radiative rates, and level lifetimes with high precision are the essential parameters for the abundance analysis, simulation, and diagnostics in fusion and astrophysical plasmas. In this work, we mainly focus on reviewing our two projects performed in the past decade. One is about the ions with Z■30 that are generally of astrophysical interest, and the other one is about the highly charged krypton(Z = 36)and tungsten(Z = 74) ions that are relevant in research of magnetic confinement fusion. Two different and independent methods, namely, multiconfiguration Dirac–Hartree–Fock(MCDHF) and the relativistic many-body perturbation theory(RMBPT) are usually used in our studies. As a complement/extension to our previous works for highly charged tungsten ions with open M-shell and open N-shell, we also mainly focus on presenting and discussing our complete RMBPT and MCDHF calculations for the excitation energies, wavelengths, electric dipole(E1), magnetic dipole(M1), electric quadrupole(E2), and magnetic quadrupole(M2) transition properties, and level lifetimes for the lowest 148 levels belonging to the 3l3configurations in Al-like W61+. We also summarize the uncertainties of our systematical theoretical calculations, by cross-checking/validating our datasets from our RMBPT and MCDHF calculations, and by detailed comparisons with available accurate observations and other theoretical calculations. The data are openly available in Science Data Bank at https://doi.org/10.57760/sciencedb.10569.展开更多
The mass-and field-shift parameters of the two 2s^(2)S_(1/2)→ 2p^(2)P_(1/2,3/2) transitions in the Li-like Ca ions are calculated by using multi-configuration Dirac-Hartree-Fock(MCDHF) and the relativistic configurat...The mass-and field-shift parameters of the two 2s^(2)S_(1/2)→ 2p^(2)P_(1/2,3/2) transitions in the Li-like Ca ions are calculated by using multi-configuration Dirac-Hartree-Fock(MCDHF) and the relativistic configuration interaction(RCI) methods with the inclusion of the transverse photon(Breit) interaction,vacuum polarization and self-energy corrections.In addition,the mass shift and field shift of these two transitions are calculated,where the field shift is calculated by using the evaluated value δ(r^(2)) obtained by [Atomic Data and Nuclear Data Tables 99 69(2013)].It is found that the mass shift of Li-like Ca ions is greater than the field shift.展开更多
Based on the multiconfiguration Dirac-Hartree-Fock(MCDHF)method,similar models are employed to simultaneously calculate the first-order and second-order Zeeman coefficients as well as the hyperfine interaction constan...Based on the multiconfiguration Dirac-Hartree-Fock(MCDHF)method,similar models are employed to simultaneously calculate the first-order and second-order Zeeman coefficients as well as the hyperfine interaction constants of the related energy levels of ^(27)Al^(+)and its logical ions ^(9)Be^(+)and^(25)Mg^(+)in the^(27)Al^(+)optical clock.With less than 0.34%deviations from experimental values in Zeeman coefficients of^(27)Al^(+),these calculated parameters will be of great help for better evaluation of the systematic uncertainty.We also calculate the isotope shift parameters of the related energy levels,which could extend our knowledge and understanding of nuclear properties of these ions.展开更多
Excitation energies, magnetic dipole, and electric quadrupole transition probabilities of the 3d^2 D_(3/2)–3d^2D_(5/2) transition in the potassium-like(K-like) sequence with 26≤Z≤36 are investigated by using the mu...Excitation energies, magnetic dipole, and electric quadrupole transition probabilities of the 3d^2 D_(3/2)–3d^2D_(5/2) transition in the potassium-like(K-like) sequence with 26≤Z≤36 are investigated by using the multi-configuration Dirac–Hartree–Fock(MCDHF) method. The contributions of the electron correlations, Breit interaction, and the leading-order quantum electrodynamic(QED) effects on the transition properties are analyzed. The present results are interested in the laboratory tokamak and the astronomical observations. Furthermore, the feasibility of these ions for the highly charged ion(HCI) clocks is discussed. Considering the wavelength of lasers and manipulation process of the atomic clocks, Cu^(10+)and Zn^(11+)are recommended as promising candidates with achievable quality factors at the 10^(15) level.展开更多
Accurate isotope shift factors of the 2s2p^(3,1)P_1~o–2s^2 ~1S_0 transitions in B II, obtained with the multi-configuration Dirac–Hartree–Fock and the relativistic configuration interaction methods, are reported. W...Accurate isotope shift factors of the 2s2p^(3,1)P_1~o–2s^2 ~1S_0 transitions in B II, obtained with the multi-configuration Dirac–Hartree–Fock and the relativistic configuration interaction methods, are reported. We found a linear correlation relation between the mass shift factors and the energies for the transitions concerned, considering all-order electron correlations. This relation is important for estimating the uncertainty in the calculation of isotope shift factors. These atomic data can be used to extract the nuclear mean-square charge radii of the boron isotopes with halo structures or to resolve the high precise spectroscopy of B II in astronomical observation.展开更多
Weak- and hyperfine-interaction-induced 1s2s1S0→ 1s2 1S0E1 transition rates for the isoelectronic sequence of Helike ions have been calculated using the multi-configuration Dirac–Hartree–Fock(MCDHF) and relativisti...Weak- and hyperfine-interaction-induced 1s2s1S0→ 1s2 1S0E1 transition rates for the isoelectronic sequence of Helike ions have been calculated using the multi-configuration Dirac–Hartree–Fock(MCDHF) and relativistic configuration interaction methods. The results should be helpful for the future experimental investigations of parity non-conservation effects.展开更多
Based on relativistic wave functions from multiconfiguration Dirac–Hartree–Fock and configuration interaction calculations, E2 and M1 transition probabilities of 2p^3 ~4S_(3/2)–2 p^3 ~2D_(3/2,5/2) are investigated ...Based on relativistic wave functions from multiconfiguration Dirac–Hartree–Fock and configuration interaction calculations, E2 and M1 transition probabilities of 2p^3 ~4S_(3/2)–2 p^3 ~2D_(3/2,5/2) are investigated in the nitrogen-like sequence with7 ≤ Z ≤ 16. The contributions of the electron correlations, Breit interaction, and the quantum electrodynamic(QED) effects on the transition properties are analyzed. The present results can be used for diagnosing plasma. In addition, several N-like ions can also be recommended as a promising candidate for a highly charged ion(HCI) clock with a quality factor(Q) of transition as high as 10^(20).展开更多
Highly charged nickel ions have been suggested as candidates for the ultra-precise optical clock, meanwhile the relevant experiment has been carried out. In the framework of the multiconfiguration Dirac–Hartree–Fock...Highly charged nickel ions have been suggested as candidates for the ultra-precise optical clock, meanwhile the relevant experiment has been carried out. In the framework of the multiconfiguration Dirac–Hartree–Fock(MCDHF)method, we calculated the hyperfine interaction constants, the Landég-factors, and the electric quadrupole moments for the low-lying states in the 61Ni11+,61Ni12+,61Ni14+, and61Ni15+ ions. These states are clock states of the selected clock transitions in highly charged nickel ions(see Fig. 1). Based on discussing the effects of the electron correlations, the Breit interaction, and quantum electrodynamics(QED) effect on these physical quantities, reasonable uncertainties were obtained for our calculated results. In addition, the electric quadrupole frequency shifts and the Zeeman frequency shifts of the clock transitions concerned were analyzed.展开更多
The quantum field theory approach has been proposed for the description of graphene electronic properties. It generalizes massless Dirac fermion model and is based on the Dirac-Hartree-Fock self-consistent field appro...The quantum field theory approach has been proposed for the description of graphene electronic properties. It generalizes massless Dirac fermion model and is based on the Dirac-Hartree-Fock self-consistent field approximation and assumption on antiferromagnetic ordering of graphene lattice. The developed approach allows asymmetric charged carriers in single layer graphene with partially degenerated Dirac cones.展开更多
铜原子能级结构的理论计算具有非常大的挑战性。本文基于多组态Dirac-Hartree-Fock(MCDHF)方法和相对论组态相互作用(RCI)方法,通过三个大规模的关联模型计算了单激发态3d^104p2P1/2、双激发态3d94s(3D)5s4D3/2,1/2,3d94s(3D)5s2D3/2,3d...铜原子能级结构的理论计算具有非常大的挑战性。本文基于多组态Dirac-Hartree-Fock(MCDHF)方法和相对论组态相互作用(RCI)方法,通过三个大规模的关联模型计算了单激发态3d^104p2P1/2、双激发态3d94s(3D)5s4D3/2,1/2,3d94s(3D)5s2D3/2,3d94s(1D)5s2D3/2以及离子态3d101S0能级和波函数。结果表明,铜原子能级结构对有限组态空间的选择极其敏感,双激发态3d94s(3D)5s4D3/2,1/2,3d94s(3D)5s2D3/2,3d94s(1D)5s2D3/2和离子态3d101S0与单激发态之间的能量差相对于已有实验结果均存在大约-0.4 e V的偏差,而计算得到的共振电子能量与实验结果符合得较好。此外,根据辐射跃迁矩阵元和非辐射跃迁矩阵元计算了双激发态的Fano参数q,并基于Fano理论得到了铜单激发态3d^104p2P1/2的总光电离截面,该理论考虑了直接光电离与光激发自电离之间的干涉效应,即共振3d94s(3D)5s4D3/2,1/2、3d94s(3D)5s2D3/2和3d94s(1D)5s2D3/2具有明显的非对称的Fano轮廓,表明光电离过程与光激发自电离过程之间的干涉对双激发态共振附近的光电离截面轮廓有着极其重要的影响。展开更多
基金Project supported by the National Key Research and Development Program of China(Grant No.2017YFA0402300)the National Natural Science Foundation of China(Grant Nos.11774292,11804280,11874051,and 11864036)+1 种基金the Scientific Research Funding of the Higher Education Institutions of Gansu Province of China(Grant No.2018A-002)the Major Project of the Research Ability Promotion Program for Young Scholars of Northwest Normal University of China(Grant No.NWNU-LKQN2019-5)。
文摘Based on the fully relativistic multiconfiguration Dirac-Hartree-Fock(MCDHF)method and the corresponding program package GRASP2018,a new program for calculating the polarizabilities is developed.As the first application,the static electric-dipole polarizabilities of the ground state 2s^(2)^(1)S_(0) and excited state 2s2p^(3)P_(0) of beryllium are calculated.By means of these polarizabilities,the blackbody radiation(BBR)shift of the 2s2p^(3)P_(0)→2s^(2)^(1)S_(0)clock transition is determined.The present results agree very well with other available theoretical results.
基金the support from the National Natural Science Foundation of China (Grant Nos. 12074081 and 12104095)。
文摘Atomic radiative data such as excitation energies, transition wavelengths, radiative rates, and level lifetimes with high precision are the essential parameters for the abundance analysis, simulation, and diagnostics in fusion and astrophysical plasmas. In this work, we mainly focus on reviewing our two projects performed in the past decade. One is about the ions with Z■30 that are generally of astrophysical interest, and the other one is about the highly charged krypton(Z = 36)and tungsten(Z = 74) ions that are relevant in research of magnetic confinement fusion. Two different and independent methods, namely, multiconfiguration Dirac–Hartree–Fock(MCDHF) and the relativistic many-body perturbation theory(RMBPT) are usually used in our studies. As a complement/extension to our previous works for highly charged tungsten ions with open M-shell and open N-shell, we also mainly focus on presenting and discussing our complete RMBPT and MCDHF calculations for the excitation energies, wavelengths, electric dipole(E1), magnetic dipole(M1), electric quadrupole(E2), and magnetic quadrupole(M2) transition properties, and level lifetimes for the lowest 148 levels belonging to the 3l3configurations in Al-like W61+. We also summarize the uncertainties of our systematical theoretical calculations, by cross-checking/validating our datasets from our RMBPT and MCDHF calculations, and by detailed comparisons with available accurate observations and other theoretical calculations. The data are openly available in Science Data Bank at https://doi.org/10.57760/sciencedb.10569.
基金Project supported by the National Natural Science Foundation of China(Grant No.11864036)the Funds for Creative Research Groups of Gansu Province,China(Grant No.20JR5RA541)。
文摘The mass-and field-shift parameters of the two 2s^(2)S_(1/2)→ 2p^(2)P_(1/2,3/2) transitions in the Li-like Ca ions are calculated by using multi-configuration Dirac-Hartree-Fock(MCDHF) and the relativistic configuration interaction(RCI) methods with the inclusion of the transverse photon(Breit) interaction,vacuum polarization and self-energy corrections.In addition,the mass shift and field shift of these two transitions are calculated,where the field shift is calculated by using the evaluated value δ(r^(2)) obtained by [Atomic Data and Nuclear Data Tables 99 69(2013)].It is found that the mass shift of Li-like Ca ions is greater than the field shift.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11604385 and 91536106)the Natural Science Foundation of Hunan Province,China(Grant No.2019JJ50743)the Research Project of the National University of Defense Technology(Grant No.ZK17-03-11)。
文摘Based on the multiconfiguration Dirac-Hartree-Fock(MCDHF)method,similar models are employed to simultaneously calculate the first-order and second-order Zeeman coefficients as well as the hyperfine interaction constants of the related energy levels of ^(27)Al^(+)and its logical ions ^(9)Be^(+)and^(25)Mg^(+)in the^(27)Al^(+)optical clock.With less than 0.34%deviations from experimental values in Zeeman coefficients of^(27)Al^(+),these calculated parameters will be of great help for better evaluation of the systematic uncertainty.We also calculate the isotope shift parameters of the related energy levels,which could extend our knowledge and understanding of nuclear properties of these ions.
基金supported by the National Natural Science Foundation of China(Grant Nos.91436103,91536102,and 91336211)the Research Programme of National University of Defense Technology,China(Grant No.JC15-0203)the Strategic Priority Research Programme of the Chinese Academy of Sciences(Grant No.XDB21030300)
文摘Excitation energies, magnetic dipole, and electric quadrupole transition probabilities of the 3d^2 D_(3/2)–3d^2D_(5/2) transition in the potassium-like(K-like) sequence with 26≤Z≤36 are investigated by using the multi-configuration Dirac–Hartree–Fock(MCDHF) method. The contributions of the electron correlations, Breit interaction, and the leading-order quantum electrodynamic(QED) effects on the transition properties are analyzed. The present results are interested in the laboratory tokamak and the astronomical observations. Furthermore, the feasibility of these ions for the highly charged ion(HCI) clocks is discussed. Considering the wavelength of lasers and manipulation process of the atomic clocks, Cu^(10+)and Zn^(11+)are recommended as promising candidates with achievable quality factors at the 10^(15) level.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.91436103,11404025,and 91536106)the Research Program of National University of Defense Technology,China(Grant No.JC15-0203)the China Postdoctoral Science Foundation(Grant No.2014M560061)
文摘Accurate isotope shift factors of the 2s2p^(3,1)P_1~o–2s^2 ~1S_0 transitions in B II, obtained with the multi-configuration Dirac–Hartree–Fock and the relativistic configuration interaction methods, are reported. We found a linear correlation relation between the mass shift factors and the energies for the transitions concerned, considering all-order electron correlations. This relation is important for estimating the uncertainty in the calculation of isotope shift factors. These atomic data can be used to extract the nuclear mean-square charge radii of the boron isotopes with halo structures or to resolve the high precise spectroscopy of B II in astronomical observation.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11274254,11147108,10979007,U1331122,and U1332206)in part by the National Basic Research Program of China(Grant No.2013CB922200)
文摘Weak- and hyperfine-interaction-induced 1s2s1S0→ 1s2 1S0E1 transition rates for the isoelectronic sequence of Helike ions have been calculated using the multi-configuration Dirac–Hartree–Fock(MCDHF) and relativistic configuration interaction methods. The results should be helpful for the future experimental investigations of parity non-conservation effects.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11604385 and 91436103)
文摘Based on relativistic wave functions from multiconfiguration Dirac–Hartree–Fock and configuration interaction calculations, E2 and M1 transition probabilities of 2p^3 ~4S_(3/2)–2 p^3 ~2D_(3/2,5/2) are investigated in the nitrogen-like sequence with7 ≤ Z ≤ 16. The contributions of the electron correlations, Breit interaction, and the quantum electrodynamic(QED) effects on the transition properties are analyzed. The present results can be used for diagnosing plasma. In addition, several N-like ions can also be recommended as a promising candidate for a highly charged ion(HCI) clock with a quality factor(Q) of transition as high as 10^(20).
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11704398 and 11934014)the National Key Research and Development Program of China(Grant No.2017YFA0304402)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB21030300)。
文摘Highly charged nickel ions have been suggested as candidates for the ultra-precise optical clock, meanwhile the relevant experiment has been carried out. In the framework of the multiconfiguration Dirac–Hartree–Fock(MCDHF)method, we calculated the hyperfine interaction constants, the Landég-factors, and the electric quadrupole moments for the low-lying states in the 61Ni11+,61Ni12+,61Ni14+, and61Ni15+ ions. These states are clock states of the selected clock transitions in highly charged nickel ions(see Fig. 1). Based on discussing the effects of the electron correlations, the Breit interaction, and quantum electrodynamics(QED) effect on these physical quantities, reasonable uncertainties were obtained for our calculated results. In addition, the electric quadrupole frequency shifts and the Zeeman frequency shifts of the clock transitions concerned were analyzed.
文摘The quantum field theory approach has been proposed for the description of graphene electronic properties. It generalizes massless Dirac fermion model and is based on the Dirac-Hartree-Fock self-consistent field approximation and assumption on antiferromagnetic ordering of graphene lattice. The developed approach allows asymmetric charged carriers in single layer graphene with partially degenerated Dirac cones.
基金National Natural Science Foundation of China(11320101003,11204243)Scientific Research Foundation of Physics of CPEE NWNU~~
文摘铜原子能级结构的理论计算具有非常大的挑战性。本文基于多组态Dirac-Hartree-Fock(MCDHF)方法和相对论组态相互作用(RCI)方法,通过三个大规模的关联模型计算了单激发态3d^104p2P1/2、双激发态3d94s(3D)5s4D3/2,1/2,3d94s(3D)5s2D3/2,3d94s(1D)5s2D3/2以及离子态3d101S0能级和波函数。结果表明,铜原子能级结构对有限组态空间的选择极其敏感,双激发态3d94s(3D)5s4D3/2,1/2,3d94s(3D)5s2D3/2,3d94s(1D)5s2D3/2和离子态3d101S0与单激发态之间的能量差相对于已有实验结果均存在大约-0.4 e V的偏差,而计算得到的共振电子能量与实验结果符合得较好。此外,根据辐射跃迁矩阵元和非辐射跃迁矩阵元计算了双激发态的Fano参数q,并基于Fano理论得到了铜单激发态3d^104p2P1/2的总光电离截面,该理论考虑了直接光电离与光激发自电离之间的干涉效应,即共振3d94s(3D)5s4D3/2,1/2、3d94s(3D)5s2D3/2和3d94s(1D)5s2D3/2具有明显的非对称的Fano轮廓,表明光电离过程与光激发自电离过程之间的干涉对双激发态共振附近的光电离截面轮廓有着极其重要的影响。
