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1.
We evaluate the nuclear-polarization energy shifts for one-electron 20882Pb and 23892U ions. In contrast to previous calculations, the effect of nuclear polarizability is found to be essentially of minor significance for high-precision measurements of the Lamb shift in heavy multicharged ions. The calculations are carried out employing different numerical methods. We also provide a comparison of our numerical results with analytical estimates. 相似文献
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V. S. Malyshevsky G. V. Fomin I. A. Ivanova 《Journal of Experimental and Theoretical Physics》2016,122(2):209-215
The problem of the transition radiation of multicharged ions at the interface between two media and in a thin plate under the charge-exchange conditions has been solved. It has been shown that the processes of pickup (or loss) of electrons by accelerated multicharged ions at the interface between two media significantly increases the yield of transition radiation. 相似文献
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《Physics Reports》1988,164(6):315-375
Modern experimental and theoretical methods to investigate multicharged ion spectra are reviewed, including the study of radiation and cooperative electron-nuclear effects. A theoretical approach to study the spectroscopic characteristics of heavy and superheavy multicharged ions is presented. Some new results for He-, Li- and Ne-like systems are listed. 相似文献
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We study the neutralization of negative hydrogen ions in collisions with multicharged fast ions (including relativistic ions)
by using an approach that allows a simple expression for the neutralization cross section to be derived over a range of collision
parameters where the standard Born approximation breaks down.
Zh. éksp. Teor. Fiz. 115, 1549–1560 (May 1999) 相似文献
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The eikonal approach to electron capture developed in earlier publications is analyzed with respect to its physical content using the Born series as a reference expansion. In the language of perturbation theory, the eikonal approach describes a close collision between electron and projectile followed by multiple distant collisions between electron and target nucleus. The distant encounters have a large weight in phase space and therefore dominate capture at intermediate energies. The post-prior discrepancy is shown to be fairly small for nonresonant 1s-1s capture. 相似文献
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We use the eikonal approximation to develop a general formula for the cross sections of inelastic collisions of multicharged
fast ions (including relativistic ions) with atoms that is applicable within a broad range of collision energies, has the
standard nonrelativistic limit, and becomes, in the ultrarelativistic case, the well-known result that follows from the exact
solution of the Dirac equation. As an example we study the excitation and ionization of a hydrogenlike atom, the single and
double excitation and ionization of a heliumlike atom, and multiple (up to the eighth order) ionization of the neon atom and
(up to eighteenth order) ionization of the argon atom. We derive simple analytical expressions for the inelastic cross sections
and establish recurrence relations linking the cross sections of ionization of different orders. Finally, we compare our results
with the experimental data.
Zh. éksp. Teor. Fiz. 114, 1646–1660 (November 1998) 相似文献
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R. V. Volkov V. M. Gordienko I. M. Lachko A. B. Savel’ev D. S. Uryupina 《JETP Letters》2007,85(1):23-26
Experimental results on the spectra of residual impurity ions from a plasma created on the surface of a tungsten target that is irradiated by a femtosecond laser pulse and is subjected to preliminary pulsed laser cleaning are reported. It is shown that deep modulation corresponding to the formation of a quasi-monoenergetic ion beam appears in the energy spectra of protons and light multicharged carbon ions in this case. The position of a “dip” at the scale of velocities closely correlates with the position of the front of heavier ions. 相似文献
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A thermodynamic approach to the sputtering of materials by slow multicharged ions is developed based on the cavitation mechanism of fracture of the surface layer of a target. It is shown that a strong electric field of a slow multicharge ion approaching the surface of a dielectric target leads to the formation of an extended metastable subsurface region. Cavities spontaneously appearing in this region form a percolation cluster leading to the fracture (cavitational electroexplosive erosion) of the target material. Universal relationships established between the volume of the region of fracture, on the one hand, and the ion charge and the target surface properties, on the other hand, qualitatively agree with experimental data on the sputtering of LiF and SiO2 by slow argon and xenon ions. 相似文献
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G. M. Filippov V. A. Aleksandrov 《Bulletin of the Russian Academy of Sciences: Physics》2016,80(2):125-128
The problem of pore formation during the propagation of Xe+q ions with energies of around 50 keV and charges q = 20–54 through an ultrathin carbon film is discussed. The results from calculations suggest that pore formation can be attributed to the perforation of part of a bombarded film by the moving wave packet of a xenon ion with a sufficiently high charge. 相似文献
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Andreas Kornath Oliver Blecher Frank Neumann Ralf Ludwig 《Journal of Molecular Spectroscopy》2003,219(1):170-174
The tetramethylpnikogenonium ions (CH3)4X+ (X = N, P, As, Sb) have been studied by infrared and Raman spectroscopy. Additionally, their structures and vibrational frequencies were ab initio calculated at the HF/6-31+G* and for (CH3)4Sb+ at the HF/6-31+G*/LANL2DZ level of theory. For the tetrahedral cations an assignment of the vibrational frequencies is discussed on the basis of a comparison of calculated and measured frequencies. 相似文献
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The purely QED effect of double radiative interference in the recombination of electrons with heavy multicharged ions is discussed.
Numerical calculations of the corresponding cross sections in the vicinities of the KL
12
M
12 and KM
12
M
12 dielectronic recombination resonances of heliumlike uranium are reported. The possibility of near-future experimental observation
of the effect with the Super-EBIT facility is suggested.
Pis’ma Zh. éksp. Teor. Fiz. 68, No. 7, 552–556 (10 October 1998)
Published in English in the original Russian journal. Edited by Steve Torstveit. 相似文献
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S. S. Anan’ev S. A. Dan’ko Yu. G. Kalinin Fan Ye Yi Qin Shuqing Jiang Feibiao Xue Zhenghong Li Jianlun Yang Rongkun Xu 《JETP Letters》2010,92(11):735-741
The dynamics of the hot component of the plasma of imploding multiwire arrays has been analyzed using the time behavior of
the X-ray spectral lines of multicharge ions. The spectra of H- and He-like aluminum ions with nanosecond time resolution
have been detected using electron-optical chronography in experiments on the implosion of multiwire arrays by mega-ampere
currents. The simultaneous appearance of the resonance lines of H- and He-like ions implies that the hot plasma whose electron
temperature is higher than 0.5 keV has existed on the axis before the implosion of the main mass of the liner. The further
dynamics of the intensity of the lines is primarily attributed to an increase in the mass of the emitting plasma. 相似文献
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V. P. Efremov S. A. PikuzJr. A. Ya. Faenov O. Rosmej I. Yu. Skobelev A. V. Shutov D. H. H. Hoffmann V. E. Fortov 《JETP Letters》2005,81(8):378-382
X-ray spectroscopic data are reported on the state of a silicon aerogel medium (SiO2) irradiated by a Ni ion flux with an energy of 4.7 MeV/nucleon. Radiation from the electron transitions to the K shell in multicharged Si ions is detected with spatial resolution along the direction of the beam propagation in the medium. Calculations performed for the ionization state and population of the levels excited in the silicon atoms of the target provide the estimate Te = 70–120 eV for the medium electron temperature in the ion tack region. Two-dimensional hydrodynamic calculations provide the estimate Te = 60–116 eV for the same conditions and densities of 0.5–2.5 g/cm3 of the excited target medium. 相似文献