[en] Classification of states of three or four equivalent fermions has been studied, i.e. possible terms and their multiplicities have been determined. For this purpose either the group theory or evident expressions for the fractional-parentage coefficients have been used. In the first approach the formulas obtained by other authors for the multiplicities of terms through the characters of the transformation matrices of bond moments have been used. This approach happens to be more general as compared with the second one, as expressions for the fractional-parentage coefficients in many cases are not known. The multiplicities of separate terms have been determined. It has been shown that the number of terms of any multiplicity becomes constant when l or j is increased

[en] Short note

[en] The ionization degree of the many-electron atoms in the field of lazer radiation is evaluated using the universal Gaspar potential. The dependence of the ionization degree of atoms on the electric field strength is derived, and it is shown to be close in its extreme cases to the one obtained in the Thomas-Fermi approximation. The results may also be applied for the low density laser plasma

[en] The energies of multielectron excitations of the M shell of argon atoms and ions are computed. The (3s, 3p)sup(8-x)(4s, 3d)sup(x) excited configurations closest to the basic configurations of an atom or an ion are considered. The results have been used to obtain characteristic excess energy losses in Ar⁺ - Ar and Ar - Ar collisions with about a half of excited electrons being radiated as a result of the Auger transitions. The single-configuration Hartree-Fock equations for the configurations have been solved on the BESM-6 computer. Then the energy matrices for the electrostatic and spin-orbit interactions have been composed and diagonalized. The results are presented in the form of tables

[en] Possibilities of the modified WKB method, in which the Gaspar universal potential is used, are studied for the investigation of atom excitation states. The calculations are performed with four modifications of the universal for the copper and silver atoms in various of excitation of the valent electron

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No abstract available