The spin studies at Nuclotron require fast and precise determination of the deuteron and proton beam polarization. For these purposes new powerful VME-based data acquisition (DAQ) system has been ...designed for the Deuteron Spin Structure setup placed at the Nuclotron Internal Target Station. The DAQ system is built using the netgraph-based data acquisition and processing framework ngdp. The software dealing with VME hardware is a set of netgraph nodes in form of the loadable kernel modules, so works in the operating system kernel context. The specific for current implementation nodes and user context utilities are described. The online events representation by ROOT classes allows us to generalize code for histograms filling and polarization calculations. The DAQ system was successfully used during 53rd and 54th Nuclotron runs, and their suitability for online polarimetry is demonstrated.
The possibility to use the
pp
-,
pd
- and
dd
-elastic scattering for the polarimetry at NICA using the existing experimental data is discussed. The first results of the simulation of these processes ...at the total energy up to 27 GeV for the segmented scintillation counter are presented.
Properties of the perovskite ferroelectrics Na
0.5
Bi
0.5
TiO
3
(NBT), K
0.5
Bi
0.5
TiO
3
(KBT) and their solid solutions are reviewed. Consideration of the NBT behavior draws attention to phenomena ...of the ion ordering, coexistence of several phase regions within a crystal lattice, phase transition diffusion and to a quite new phenomenon: existence of the isotropization points (temperatures) in the AFE-phase-temperature interval. In the KBT the isotropic points are absent. NBT, KBT, and their solid solutions are considered as possible useful materials for technical (in particular, for piezoelectric) applications. There are also some other A
0.5
+
Bi
0.5
B
4+
O
3
perovskites which are interesting for future research.
The potential well formed by the repulsive continuous potentials of three neighboring 111 chains in a silicon crystal, for a positively charged particle, exhibits the symmetry of an equilateral ...triangle, described by the
group. In this case, the previously developed procedure for finding the eigenvalues of the transverse motion energy of channeled positively charged particles (positrons or protons) and the corresponding eigenfunctions of the Hamiltonian, implemented on a square spatial grid, leads to artifacts in numerical modeling. We present a modification of the modeling algorithm based on a hexagonal grid, which takes into account the symmetry of the problem. The results of both approaches are compared, demonstrating the absence of artifacts when using a hexagonal grid. Using numerical methods, all discrete energy levels of the transverse motion of channeled positrons with a longitudinal motion energy of 2, 2.5, 3, 3.5, and 4 GeV in the discussed potential well are found. The developed procedure can be used in studies of manifestations of dynamic tunneling and quantum chaos in channeling.
The article is devoted to the study of migration of the USSR population in the pre-war years (1939-1940). Along with the analysis of the number of migrants and direction of migration flows, the ...authors also demonstrate the increasing control functions of the state in the field of population movement in the USSR. Based on the analysis of a wide range of historical sources, many of which are being introduced into scientific circulation for the first time ever, the authors have developed an original classification of the pre-war migration.
The article is devoted to the USSR population in the pre-war years, determines its components with population migration being one of them. The article concludes that the socio-economic causes of migration are interrelated with the political (mainly foreign policy) ones. The pre-war migration is also characterized by a latent nature, a combination of planned and spontaneous movements with the desire of the state to take the latter under control. The practice of forced displacement of the population, including from the annexed territories continued during the period under study.
An important part of the USSR migration were military mobilizations, forced deportations of large groups of population, recruitment of labour, and agricultural resettlement. At the same time, spontaneous relocations outside the state control played a significant role in forming migration flows.
The movement of charged particles in a crystal can be both regular and chaotic. At the quantum level, chaos manifests itself in the statistical properties of the set of energy levels. Systems, in ...which regions of regular motion are separated in the phase space by a region of dynamic chaos, are of particular interest. The statistics of the energy levels of such systems substantially depends on the possibility of tunneling between phase-space domains that are dynamically isolated from each other. Consideration of this effect leads to the Podolskiy–Narimanov distribution function. In this study, we estimate the matrix elements of such tunneling transitions in the problem of the transverse motion of positrons with energies of 20 and 40 GeV, which are transmitted in the axial channeling mode in the 100 direction of a silicon crystal. The Podolskiy–Narimanov distribution parameter is found on the basis of this estimate, and it is shown that the former actually describes the statistics of the distances between neighboring energy levels of the transverse motion.
The motion of charged particles in the crystal can be both regular and chaotic. Within the quantum approach, chaos manifests itself in the statistical properties of the set of energy levels. The ...systems in which regions of regular motion are separated by that of chaotic motion in phase space are of special interest. The statistics of levels of these systems is greatly influenced by the possibility of tunneling between phase-space regions dynamically isolated from each other. Matrix elements for such tunneling transitions are estimated in the present paper. To do this, all transverse-motion energy levels of 20 GeV positrons moving in the axial-channeling mode along the Si crystal 100 direction, as well as the Hamiltonian eigenfunctions corresponding to these states, are calculated numerically. The superposition of these eigenfunctions that correspond to classical orbits localized in symmetric but dynamically isolated regions of phase space are found. The energy-level splitting makes it possible to estimate the tunneling-transition matrix elements.
The main trends in the genesis of epidemiological transition are discussed. The geographical scope of this article is limited to a typical provincial region of Russia, Western Siberia. Based on the ...analysis of changes in the structure of the causes of mortality in their historical retrospective, several attempts at epidemiological transition that ended with a false start have been identified.
The spectral method applicability to the problem of the charged particles axial channeling is studied. The quantum state characteristics for the electron motion near the atomic string 110 direction ...of the silicon crystal are obtained using this method of Schrödinger equation numerical solution. The full set of eigenenergies and eigenfunctions for the electron with longitudinal energy of 5 MeV is computed. The results obtained illustrate the difference in the wave function morphology for regular and chaotic cases.
The dp breakup reaction has been investigated by the scintillation detectors placed at the vicinity of Internal Target Station (ITS) of Nuclotron. Data have been obtained at the angles of 19° - 54° ...in the laboratory frame at the deuteron energy of 300 - 500 MeV in a various detector configurations in which the sensitivity to the three nucleon correlations and relativistic effects are assumed. Preliminary results of the five fold differential cross section for particular detector configurations of the dp breakup reaction at 400 MeV of deuteron energy have been obtained.
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