The Landé g factors of Ba+are very important in high-precision measurement physics.The wave functions,energy levels,and Landég factors for the 6s ^(2)S_(1/2) and 5d 2D_(3/2,5/2) states of Ba+ions were calcul...The Landé g factors of Ba+are very important in high-precision measurement physics.The wave functions,energy levels,and Landég factors for the 6s ^(2)S_(1/2) and 5d 2D_(3/2,5/2) states of Ba+ions were calculated using the multi-configuration Dirac-Hartree-Fock method and the model-quantum electrodynamics(QED)method.The contributions of the electron correlation effects and QED effects were discussed in detail.The transition energies are in excellent agreement with the experimental results,with differences of approximately 5 cm^(−1).The presently calculated g factor of 2.0024905(16)for the 6S1/2 agrees very well with the available experimental and theoretical results,with a difference at a level of 10^(−6).For the 5D_(3/2,5/2) states,the present results of 0.7993961(126)and 1.2003942(190)agree with the experimental results of 0.7993278(3)[Phys.Rev.A 541199(1996)]and 1.20036739(14)[Phys.Rev.Lett.124193001(2020)]very well,with differences at the level of 10−5.展开更多
The transition energies of the 1s^(2)2s^(2)S_(1/2)→1s^(2)2p^(2)p_(1/2,3/2)transitions in Li-like Th87+ions were calculated by combining the multi-configuration Dirac-Hartree-Fock(MCDHF)method with the model-quantum e...The transition energies of the 1s^(2)2s^(2)S_(1/2)→1s^(2)2p^(2)p_(1/2,3/2)transitions in Li-like Th87+ions were calculated by combining the multi-configuration Dirac-Hartree-Fock(MCDHF)method with the model-quantum electrodynamics(modelQED)approach.The effects of electron correlation,Breit interaction,and QED effects were analyzed in detail.The isotope shifts,including the mass shifts and field shifts,due to the 2s2S_(1/2)→2p^(2)P_(1/2,3/2)transitions were then calculated using two different methods,namely,the MCDHF method and the finite-field method.The results show that these two methods are in excellent agreement.展开更多
Fundamental quantum transport equation for impact-ionization processes in fusion plasmas is formulated in the actor-spectator description.The density-matrix formulism is adopted to treat both coherent and incoherent e...Fundamental quantum transport equation for impact-ionization processes in fusion plasmas is formulated in the actor-spectator description.The density-matrix formulism is adopted to treat both coherent and incoherent effects in a unified fashion.Quantum electrodynamic effects are also considered for high-temperature scenarios.Electron-impact ionization of uranium ion U91+and proton-impact ionization of hydrogen are given as examples.展开更多
This study investigates the generation of high energy photons and positrons using focused ultrahigh intensity femtosecond laser pulses on a relativistic electron beam with a set of two-dimensional particle- in-cell si...This study investigates the generation of high energy photons and positrons using focused ultrahigh intensity femtosecond laser pulses on a relativistic electron beam with a set of two-dimensional particle- in-cell simulations. We consider circularly and linearly polarized, single and spatially separated double laser pulses. We model both 500 MeV and 1 GeV electron beams. Higher positron production is obtained using circularly polarized laser pulses. Using double pulses, the focusing effect of the ponderomotive force confines the electrons to a small volume, generating additional energetic photons and positrons. The positron spectral distributions are effectively modified by these variations. When the electron beam energy is doubled, the number of positrons increased, while the cutoff energy remained nearly constant.展开更多
基金supported by the National key Research and Development Program of China under Grant No.2022YFA1602500the National Natural Science Foundation of China under Grant Nos.12174316 and 1236040286,and 12404306。
文摘The Landé g factors of Ba+are very important in high-precision measurement physics.The wave functions,energy levels,and Landég factors for the 6s ^(2)S_(1/2) and 5d 2D_(3/2,5/2) states of Ba+ions were calculated using the multi-configuration Dirac-Hartree-Fock method and the model-quantum electrodynamics(QED)method.The contributions of the electron correlation effects and QED effects were discussed in detail.The transition energies are in excellent agreement with the experimental results,with differences of approximately 5 cm^(−1).The presently calculated g factor of 2.0024905(16)for the 6S1/2 agrees very well with the available experimental and theoretical results,with a difference at a level of 10^(−6).For the 5D_(3/2,5/2) states,the present results of 0.7993961(126)and 1.2003942(190)agree with the experimental results of 0.7993278(3)[Phys.Rev.A 541199(1996)]and 1.20036739(14)[Phys.Rev.Lett.124193001(2020)]very well,with differences at the level of 10−5.
基金Project supported by the National Key Research and Development Program of China(Grant No.2022YFA1602500)the National Natural Science Foundation of China(Grant Nos.1236040286,12474250,12174316,12464036,and12404306)+1 种基金the Young Teachers Scientific Research Ability Promotion Plan of Northwest Normal University(Grant No.NWNU-LKQN2020-10)the Funds for Innovative Fundamental Research Group Project of Gansu Province(Grant No.20JR5RA541)。
文摘The transition energies of the 1s^(2)2s^(2)S_(1/2)→1s^(2)2p^(2)p_(1/2,3/2)transitions in Li-like Th87+ions were calculated by combining the multi-configuration Dirac-Hartree-Fock(MCDHF)method with the model-quantum electrodynamics(modelQED)approach.The effects of electron correlation,Breit interaction,and QED effects were analyzed in detail.The isotope shifts,including the mass shifts and field shifts,due to the 2s2S_(1/2)→2p^(2)P_(1/2,3/2)transitions were then calculated using two different methods,namely,the MCDHF method and the finite-field method.The results show that these two methods are in excellent agreement.
文摘Fundamental quantum transport equation for impact-ionization processes in fusion plasmas is formulated in the actor-spectator description.The density-matrix formulism is adopted to treat both coherent and incoherent effects in a unified fashion.Quantum electrodynamic effects are also considered for high-temperature scenarios.Electron-impact ionization of uranium ion U91+and proton-impact ionization of hydrogen are given as examples.
基金This work was financially supported by the National Natural Science Foundation of China （NSFC） （Grant Nos. 11664039 and 11575150）, and the Doctoral Fund of Xinjiang University （Grant Nos. BS150216 and BS150217）. A. Ablat was supported by NSFC （Grant Nos. 61464010 and 61604126）. The authors are particularly grateful to CFSA at the University of War- wick for allowing us to use the EPOCH.
文摘This study investigates the generation of high energy photons and positrons using focused ultrahigh intensity femtosecond laser pulses on a relativistic electron beam with a set of two-dimensional particle- in-cell simulations. We consider circularly and linearly polarized, single and spatially separated double laser pulses. We model both 500 MeV and 1 GeV electron beams. Higher positron production is obtained using circularly polarized laser pulses. Using double pulses, the focusing effect of the ponderomotive force confines the electrons to a small volume, generating additional energetic photons and positrons. The positron spectral distributions are effectively modified by these variations. When the electron beam energy is doubled, the number of positrons increased, while the cutoff energy remained nearly constant.
