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For the three-body Coulomb problem a hyperspherical parametrisation of independent variables is given on a five-dimensional sphere S5 with a hyperradius RH, the first linear invariant of the inertia tensor. The hyperspherical adiabatic basis is defined as a complete set of eigenfunctions and eigenvalues of the Hamiltonian on the sphere S5 for every fixed value of the slow variable RH. The partial wave analysis in the total momentum J representation allows the authors to separate three Euler angles and to reduce the hyperspherical problem on S5 to a system of (J+1) two-dimensional problems. Classification is given of the hyperspherical adiabatic basis for small and large values of the hyperradius RH. The logarithmic Fock singularity at the point of triple collision (RH=0) is explicitly shown. The approach is assigned to computing the cross sections of mesic atomic processes in the muon catalysis problem.

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The problems related to the spectral line-shape formation in the scrape of layer (SOL) in fusion reactor plasma for typical observation chords are considered. The SOL plasma is characterized by the relatively low electron density (10 12-10 13 cm −3) and high temperature (from 10 eV up to 1 keV). The main effects responsible for the line-shape formation in the SOL are Doppler and Zeeman effects. The main problem is a correct modeling of the neutral atom velocity distribution function (VDF). The VDF is determined by a number of atomic processes, namely: molecular dissociation, ionization and charge exchange of neutral atoms on plasma ions, electron excitation accompanied by the charge exchange from atomic excited states, and atom reflection from the wall. All the processes take place step by step during atom motion from the wall to the plasma core. In practice, the largest contribution to the neutral atom radiation emission comes from a thin layer near the wall with typical size 10-20 cm, which is small as compared with the minor radius of modern devices including international test experimental reactor ITER (radius 2 m). The important problem is a strongly non-uniform distribution of plasma parameters (electron and ion densities and temperatures). The distributions vary for different observation chords and ITER operation regimes. In the present report, most attention is paid to the problem of the VDF calculations. The most correct method for solving the problem is an application of

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The new statistical approach for calculation of radiation processes with heavy multielectron ions in plasma is developed. The method consists in consideration of atomic structure as a condensed medium, characterized by the spectrum of elementary excitations with plasma frequency, determined by local atomic electron density. For instance, the radiation losses in this model are due to excitation of plasma type oscillations in atom under its collisions with plasma electrons and have a universal statistical representation for all sorts of multielectron ions. The calculations of radiation losses on tungsten ions are performed in the wide range of plasma temperature variation, typical for physics of high temperature plasma with magnetic confinement. It is shown that the universal statistical approach results are within the scattering of current numerical codes data. The proposed statistical method for description of complex atoms collective excitations for calculations of plasma radiation losses is of general physical interest and allows to obtain the necessary data more faster with the lesser computational resources.The calculations of radiation losses of heavy atoms in plasmas acquired particular interest due to implementation of tungsten in construction elements of current thermonuclear installations [1]. The diapason of temperature being of interest for calculations of radiation losses turns out to be extremely large -from several electron-volts in the SOL and divertor plasmas up to 40 keV in the central regions [1]. The energy structure of multielectron states of tungsten ions is very complex in all temperature diapason that requires cumbersome and time-consuming quantum mechanical calculations of atomic structure, as well as elementary processes, responsible for population of atomic levels. As under the calculations of rate coefficients the additional approximations are used, that work well only in the limited temperature diapason there are significant deviations between results of complex detailed codes [2][3]. Therefore for the description of heavy ions structure it is natural to use general statistical methods [4][5], that allow to retrieve scalings of radiation processes in all range of temperatures. In this approach the atomic spectra could be represented as collective excitations of condensed medium [4]. The proposed in present work implementation of statistical models [6][7] allows to elaborate the universal statistical approach for analysis of radiation losses and the simple method of their calculation.The statistical models are based on the notion of collective oscillations of atomic electrons plasma bunch. For the description of this oscillations in the Brandt-Lundquist model [6] the approximation of local plasma frequency (LPF) is used, connected with the local electron atomic density. In the Vinogradov-Tolsctikhin paper [7] on the basis of solution of the kinetic Vlasov equation it is shown that the approach [6] does not take into account polarization field, inducted by the external atomic pe...

The collapse of a wave function has recently reemerged as a subject of extensive discussion in the quantum mechanical literature. In the present paper, wave function collapses occurring during the irreversible evolution of complex quantum systems, including those involved in measurement procedures, are described.

The statistical method for ab initio calculations of the electron impact ionization cross sections of multielectron ions and related ionization rates is developed. It is created based on an idea of collective excitations of atomic electrons alike in condensed medium. The Thomas–Fermi model density distribution of atomic electrons is assumed and their collective oscillations are described by the local plasma frequency model. Using a proposed statistical approach the calculations of the total single electron impact ionization cross sections of multielectron ions for several chosen chemical elements from argon up to uranium, taken in the various charge states, are performed and compared with available experimental and theoretical data, demonstrating a satisfactory agreement.