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1.
The observed universal momentum distribution of the fragments of a heavy ion resulting from high energy impact with a target is explained on the basis of a simple statistical model.  相似文献   

2.
A calculation is made of the binding energy of an electron in negative ions of complex heavy Ga, In, Tl atoms in terms of the polarization potential formalism and the relativistic perturbation theory with a model potential of the zeroth-order approximation. The results obtained refine the literature data on the negative ions investigated. Odessa Hydrometereological Institute, 15, L'vovskaya St., Odessa, 270016, Ukraine. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 66, No. 1, pp. 116–119, January–February, 1999.  相似文献   

3.
An estimate for the last unknown gauge-invariant set of QED corrections of order α2, the second-order self-energy correction, is presented utilizing the so-called sign approximation. This is able to reduce the present uncertainties in Lamb-shift predictions considerably. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

4.
We propose to measure the lifetime of short-lived excited states in highly charged ions by pump-probe experiments. Utilizing two synchronized and delayed Femtosecond pulses allows accessing these lifetimes with Femtosecond precision. Such measurements could provide sensitive tests of state-of-the art atomic structure calculations beyond the capabilities of established methods.  相似文献   

5.
The binding energy of an electron to negative ions of the alkali elements Li, Na, K, Rb, Cs, and Fr is calculated on the basis of the formalism of the polarization potential and relativistic perturbation theory with the model zero-approximation potential. The results that are obtained refine data available in the literature for these negative ions. Odessa Hydrometeorological Institute. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 70–74, February, 1998.  相似文献   

6.
Within the statistical theory the analytical expression of electrostatic and exchange energies for atoms with arbitrary ionization degree in strong magnetic fields is obtained.  相似文献   

7.
The binding energy of an electron in negative ions of the alkali-earth atoms Ca, Ba is calculated based on the formalism of the polarization potential and relativistic perturbation theory with the model potential in the zeroth-order approximation. The results obtained contribute to refinement of the available literature data for the sought negative ions. Odessa Hydrometeorological Institute, 15, L’voskaya St., Odessa, 270016, Ukraine. Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 64, No. 1, pp. 108–111, January–February, 1997.  相似文献   

8.
A non-local, separable potential which matches the phase shifts up to 320 MeV and gives saturation for nuclear matter in the first order at a Fermi-momentum ofk F =1.6 f?1 with an energy per particle of ?8 MeV has been constructed byTabakin. We have employed this potential for calculations of finite nuclei using the Fermi-gas-model. The binding energy has been minimalized with respect to two parametersb andc (the surface-thickness and the radius of the nucleus). However the calculations show that an arbitrarily sharp surface is possible.  相似文献   

9.
The electron binding energy in negative ions of the alkaline-earth atoms Ca and Sr is calculated on the basis of the polarization-potential formalism and relativistic perturbation theory with a zeroth-order model potential. The results improve the data available in the literature for these negative ions. Odessa Hydrometeorological Institute. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 9, pp. 27–31, September, 1996.  相似文献   

10.
Transition energies, Coulomb repulsions and effective quantum numbers have been calculated for the doubly excited Nsnp: 3P0 (for N = 2, n = N,?, 5n = N,\ldots, 5); Nsnd: 3De (for N = 2, n=N+1, ?, 5n=N+1, \ldots, 5) and Npnd: 3F0 (for N = 2, n=N+1, ?, 5n=N+1, \ldots, 5) states for the highly stripped ions Na9+{\rm Na^{9+}}, Mg10+\rm Mg^{10+}, Al11+\rm Al^{11+}, Si12+\rm Si^{12+}, P13+\rm P^{13+} and S14+\rm S^{14+}. Time-dependent perturbation theory has been applied to calculate such transitions properties. A time-dependent harmonic perturbation causes simultaneous excitation of both the electrons with a change of spin state. The doubly excited energy levels and the analytic representation of their wave functions are obtained by identifying the poles of an appropriately constructed linearized variational functional with respect to driving frequency. Most of the results are new. The transition energies and effective quantum numbers of 2s2p: 3P0 states of all the ions agree well with the only available experimental data.  相似文献   

11.
张孟  苟秉聪 《中国物理》2005,14(8):1554-1558
采用多组态相互作用方法及Rayleigh-Ritz 变分方法,并考虑相对论修正和质量极化效应,获得了类铍离子等电子系列(Z=4-10)低激发态1s22p2p 1De和1s22p3p 3Pe的相对论能量。同时还计算了精细结构和超精细结构。计算结果与其他理论和实验符合的很好。  相似文献   

12.
Abstract

The possibility of the radiative deexcitation from channeled heavy ions excited by the Okorokov Effect (Resonant coherent excitation) is discussed and the experiments on the photon emission due to the deexcitation from hydrogen-like Ne9+ and Fe8+ ions are reported.  相似文献   

13.
In this paper, we present the structure and the dynamics of highly charged heavy ions studied through dielectronic recombination (DR) observations performed with the Tokyo electron beam ion trap. By measuring the energy dependence of the ion abundance ratio in the trap at equilibrium, we have observed DR processes for open shell systems very clearly. Remarkable relativistic effects due to the generalized Breit interaction have been clearly shown in DR for highly charged heavy ions. We also present the first result for the coincidence measurement of two photons emitted from a single DR event.  相似文献   

14.
Constraints on the EoS for symmetric matter (equal neutron and proton numbers) at supra-saturation densities have been extracted from energetic collisions of heavy ions. Collisions of neutron-deficient and neutron-rich heavy ions now provide initial constraints on the EoS of neutron-rich matter at sub-saturation densities. Comparisons are made to other available constraints.  相似文献   

15.
Measurements of the Auger decay of beam-foil excited Be II and Be I levels are reported along with a proposed assignment of the experimental spectra. The Li I, Be II and Be III (1s2s2)2S → (1s22s)2S Auger transitions as presented in this letter represents the first observation of such states in positive ions with Z?5.  相似文献   

16.
The optical dielectric function of an electron-hole plasma in highly excited polar semiconductors with a direct band gap is calculated by solving a Bethe-Salpeter equation for the polarization function. The screening of the Coulomb potential is treated in a damped phonon-plasmon-pole approximation. We include the complex dynamical self-energy corrections as well as electron-hole correlations.Project of the Sonderforschungsbereich Frankfurt/Darmstadt, financed by special funds of the Deutsche Forschungsgemeinschaft  相似文献   

17.
V B Sheorey  M S Santhanam 《Pramana》1998,50(6):535-545
Computational methods for the calculation of a large number of eigenstates of coupled oscillator system are developed and discussed. These calculations have enabled us to identify and investigate properties of an infinite set of states sharply localized in configuration space in this system. Some of the results and their significance are discussed. Extensions to three-dimensional systems are also briefly considered.  相似文献   

18.
Recombination involving the core excitation of two electrons, which may be termed trielectronic recombination, has been experimentally identified for the first time. Using Cl13+ ions circulating in the TSR heavy-ion storage ring, we have observed surprisingly strong low-energy trielectronic recombination resonances, comparable to the dielectronic process. At higher electron-ion collision energies, trielectronic recombination is suppressed due to the autoionization of the triply excited intermediate state into excited final states. The formation of the intermediate state depends sensitively on configuration mixing, making trielectronic recombination a challenge to atomic-structure calculations.  相似文献   

19.
采用多组态相互作用方法及Rayleigh- Ritz变分法,计算了类铍O4+离子1s22s2p3Po态的非相对论能量,并详细分析了如何选择质量最好的变分波函数.运用截断变分方法进一步饱和函数空间得到能量的改进量,并考虑相对论修正、质量极化效应等获得了相对论能量计算值.计算结果表明,此理论计算方法可得到高精度的能量计算值.  相似文献   

20.
M P Das 《Pramana》1983,21(2):103-110
Inner shell binding of electrons in heavy atoms is studied through the relativistic density functional theory in which many electron interactions are treated in a local density approximation. By using this theory and the Δscf procedure binding energies of several core electrons of mercury atom are calculated in the frozen and relaxed configurations. The results are compared with those carried out by the non-local Dirac-Fock Scheme.K-shell binding energies of several closed shell atoms are calculated by using the Kohn-Sham and the relativistic exchange potentials. The results are discussed and the discrepancies in our local density results, when compared with experimental values, may be attributed to the non-locality and to the many-body effects.  相似文献   

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