Energy levels, wavelengths, transition rates, oscillator strengths, and lifetimes between the 2s22p23P1,2s22p23P2,and 2s2p35S2 levels of ions in the carbon-like （C-like） isoelectronic sequence （nuclear charges Z=7...Energy levels, wavelengths, transition rates, oscillator strengths, and lifetimes between the 2s22p23P1,2s22p23P2,and 2s2p35S2 levels of ions in the carbon-like （C-like） isoelectronic sequence （nuclear charges Z=7-92） are calculated in the valence and core-valence limits using the multiconfiguration Dirac–Fock method. The Breit interaction, quantum electrodynamics （QED）, and finite nuclear mass effects are taken into account in subsequent relativistic configuration-interaction calculations. The calculated energies and transition rates are compared with the critically evaluated experimental values and other recent calculated results. Our calculated data are in good agreement with these data.展开更多
We report in this paper the ground-state energy 2s2 1S and total energies of doubly excited states 2p2 1D, 3d2 1D, 4f2 1I of the Helium isoelectronic sequence from H- to Ca18+. Calculations are performed using the Mod...We report in this paper the ground-state energy 2s2 1S and total energies of doubly excited states 2p2 1D, 3d2 1D, 4f2 1I of the Helium isoelectronic sequence from H- to Ca18+. Calculations are performed using the Modified Atomic Orbital Theory (MAOT) in the framework of a variational procedure. The purpose of this study required a mathematical development of the Hamiltonian applied to Slater-type wave function [1] combining with Hylleraas-type wave function [2]. The study leads to analytical expressions which are carried out under special MAXIMA computational program. This first proposed MAOT variational procedure, leads to accurate results in good agreement as well as with available other theoretical results than experimental data. In the present work, a new correlated wave function is presented to express analytically the total energies for the 2s2 1S ground state and each doubly 2p2 1D, 3d2 1D, 4f2 1I excited states in the He-like systems.The present accurate data may be a useful guideline for future experimental and theoretical studies in the (nl2) systems.展开更多
Influence of core property on multi-electron process in the collisions of q = 6-9 and 11 isocharged sequence ions with Ne is investigated in the keV/u region. The cross-section ratios of double-, triple-, quadruple- a...Influence of core property on multi-electron process in the collisions of q = 6-9 and 11 isocharged sequence ions with Ne is investigated in the keV/u region. The cross-section ratios of double-, triple-, quadruple- and total multielectron processes to the single electron capture process as well as the partial ratios of different reaction channels to the relevant multi-electron process are measured by using position-sensitive and time-of-flight techniques. The experimental data are compared with the theoretical predictions including the extended classical over-barrier model, the molecular Columbic barrier model and the semi-empirical scaling law. Results show a core effect on multi-electron process of isocharge ions colliding with Neon, which is consistent with the results of Helium we obtained previously.展开更多
The energy levels,transition energies,transition probabilities,weighted oscillator strengths,and line strengths of Li-like ions(Z=7-11)in dense plasmas are investigated in this work.The relativistic effects and electr...The energy levels,transition energies,transition probabilities,weighted oscillator strengths,and line strengths of Li-like ions(Z=7-11)in dense plasmas are investigated in this work.The relativistic effects and electron correlation effects are described by the MCDHF method.The ion sphere model is applied to include the dense plasma screening effect.The ground configuration 1s^(2)2s and the excited 1s^(2)2p,1s^(2)3l(l=0-2)are considered.The configuration sets are enlarged until n=7 where the calculated energy levels have converged.The critical free electron densities of 1s^(2)3d states are estimated.Except for 1s^(2)3s-1s^(2)3p transitions,the transition energies for△n=0 increase,and for△n≠0 decrease with increasing free electron densities.For 1s^(2)3s-1s^(2)3p transitions,the spectra show blue-shift at lower free electron densities and red-shift at higher free electron densities,and the energy level crossing phenomens are observed at higher free electron densities.展开更多
Under coronal conditions, the steady state rate-equations are used to calculate the inter-stage line ratios between Li-like ls22p(2P3/2)→ls22s(2S1/2) and He-like ls2p(1P1)→1s2(1S0) transitions for Ti in the electron...Under coronal conditions, the steady state rate-equations are used to calculate the inter-stage line ratios between Li-like ls22p(2P3/2)→ls22s(2S1/2) and He-like ls2p(1P1)→1s2(1S0) transitions for Ti in the electronic temperature ranges from 0.1keV to 20 keV. The results show that the temperature sensitivities are higher at the electronic temperature less than 5000 eV and the temperature sensitivities will decrease with the increase of electronic temperature.展开更多
The dependence of the ratio R1 for transfer ionization to single capture for Cq+, Nq+, Oq+, Neq+ ions on Ne target upon the electronic structure of the projectile is studied. For Aq+-Ne collisions the ratio R1 decreas...The dependence of the ratio R1 for transfer ionization to single capture for Cq+, Nq+, Oq+, Neq+ ions on Ne target upon the electronic structure of the projectile is studied. For Aq+-Ne collisions the ratio R1 decreases as the atomic number Z of the projectile increases for q=4,5,6,7 sequences which provides strong evidence for the increase of the binding energy of the target valence electron after single electron capture. The increase in binding energy depends both upon the atomic number of the projectile and the target atom.展开更多
The Schrödinger equation for the 2S and 2P states of the lithium-like ions Z=5–7,9–10 is solved by using the Rayleigh-Ritz variational method in Hylleraas coordinates.The leading-order relativistic and QED corr...The Schrödinger equation for the 2S and 2P states of the lithium-like ions Z=5–7,9–10 is solved by using the Rayleigh-Ritz variational method in Hylleraas coordinates.The leading-order relativistic and QED corrections are calculated perturbatively and higher-order corrections are estimated.The transition frequencies between the 2S_(1/2)and 2P_(J)(J=1/2,3/2)states are determined and compared with experimental and other theoretical results.Specifically,isotope shifts are also calculated for B^(2+).展开更多
基金the National Natural Science Foundation of China(Grant No.11174213)
文摘Energy levels, wavelengths, transition rates, oscillator strengths, and lifetimes between the 2s22p23P1,2s22p23P2,and 2s2p35S2 levels of ions in the carbon-like （C-like） isoelectronic sequence （nuclear charges Z=7-92） are calculated in the valence and core-valence limits using the multiconfiguration Dirac–Fock method. The Breit interaction, quantum electrodynamics （QED）, and finite nuclear mass effects are taken into account in subsequent relativistic configuration-interaction calculations. The calculated energies and transition rates are compared with the critically evaluated experimental values and other recent calculated results. Our calculated data are in good agreement with these data.
文摘We report in this paper the ground-state energy 2s2 1S and total energies of doubly excited states 2p2 1D, 3d2 1D, 4f2 1I of the Helium isoelectronic sequence from H- to Ca18+. Calculations are performed using the Modified Atomic Orbital Theory (MAOT) in the framework of a variational procedure. The purpose of this study required a mathematical development of the Hamiltonian applied to Slater-type wave function [1] combining with Hylleraas-type wave function [2]. The study leads to analytical expressions which are carried out under special MAXIMA computational program. This first proposed MAOT variational procedure, leads to accurate results in good agreement as well as with available other theoretical results than experimental data. In the present work, a new correlated wave function is presented to express analytically the total energies for the 2s2 1S ground state and each doubly 2p2 1D, 3d2 1D, 4f2 1I excited states in the He-like systems.The present accurate data may be a useful guideline for future experimental and theoretical studies in the (nl2) systems.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 10874188 and 10775160)
文摘Influence of core property on multi-electron process in the collisions of q = 6-9 and 11 isocharged sequence ions with Ne is investigated in the keV/u region. The cross-section ratios of double-, triple-, quadruple- and total multielectron processes to the single electron capture process as well as the partial ratios of different reaction channels to the relevant multi-electron process are measured by using position-sensitive and time-of-flight techniques. The experimental data are compared with the theoretical predictions including the extended classical over-barrier model, the molecular Columbic barrier model and the semi-empirical scaling law. Results show a core effect on multi-electron process of isocharge ions colliding with Neon, which is consistent with the results of Helium we obtained previously.
基金the National Natural Science Foundation of China(Grant No.11847163)the Natural Science Foundation of Gansu Province(Grant No.20JR10RA131)+2 种基金the Doctoral Science Foundation of Longdong University(Grant No.XYBY202005)the Natural Science Foundation of Shaanxi Province(Grant No.2021JQ-698)the Special Project of Department of Education of Shaanxi Province(Grant No.18JK0710).
文摘The energy levels,transition energies,transition probabilities,weighted oscillator strengths,and line strengths of Li-like ions(Z=7-11)in dense plasmas are investigated in this work.The relativistic effects and electron correlation effects are described by the MCDHF method.The ion sphere model is applied to include the dense plasma screening effect.The ground configuration 1s^(2)2s and the excited 1s^(2)2p,1s^(2)3l(l=0-2)are considered.The configuration sets are enlarged until n=7 where the calculated energy levels have converged.The critical free electron densities of 1s^(2)3d states are estimated.Except for 1s^(2)3s-1s^(2)3p transitions,the transition energies for△n=0 increase,and for△n≠0 decrease with increasing free electron densities.For 1s^(2)3s-1s^(2)3p transitions,the spectra show blue-shift at lower free electron densities and red-shift at higher free electron densities,and the energy level crossing phenomens are observed at higher free electron densities.
文摘Under coronal conditions, the steady state rate-equations are used to calculate the inter-stage line ratios between Li-like ls22p(2P3/2)→ls22s(2S1/2) and He-like ls2p(1P1)→1s2(1S0) transitions for Ti in the electronic temperature ranges from 0.1keV to 20 keV. The results show that the temperature sensitivities are higher at the electronic temperature less than 5000 eV and the temperature sensitivities will decrease with the increase of electronic temperature.
文摘The dependence of the ratio R1 for transfer ionization to single capture for Cq+, Nq+, Oq+, Neq+ ions on Ne target upon the electronic structure of the projectile is studied. For Aq+-Ne collisions the ratio R1 decreases as the atomic number Z of the projectile increases for q=4,5,6,7 sequences which provides strong evidence for the increase of the binding energy of the target valence electron after single electron capture. The increase in binding energy depends both upon the atomic number of the projectile and the target atom.
基金Project supported by the National Natural Science Foundation of China (Grant No. 11774080)supported by NSERC of Canada
文摘The Schrödinger equation for the 2S and 2P states of the lithium-like ions Z=5–7,9–10 is solved by using the Rayleigh-Ritz variational method in Hylleraas coordinates.The leading-order relativistic and QED corrections are calculated perturbatively and higher-order corrections are estimated.The transition frequencies between the 2S_(1/2)and 2P_(J)(J=1/2,3/2)states are determined and compared with experimental and other theoretical results.Specifically,isotope shifts are also calculated for B^(2+).
