Geomagnetic disturbances on ground associated with particle precipitation during SC

We have examined several cases of magnetosphere compression by solar wind pressure pulses using a set of instruments located in the noon sector of auroral zone. We have found that the increase in riometric absorption (sudden commencement absorption, SCA) occurred simultaneously with the beginning of negative or positive magnetic variations and broadband enhancement of magnetic activity in the frequency range above 0.1 Hz. Since magnetic variations were observed before the step-like increase of magnetic field at equatorial station (main impulse, MI), the negative declinations resembled the so-called preliminary impulse, PI. In this paper a mechanism for the generation of PI is introduced whereby PI's generation is linked to SCA – associated precipitation and the local enhancement of ionospheric conductivity leading to the reconstruction of the ionospheric current system prior to MI. Calculation showed that PI polarity depends on orientation of the background electric field and location of the observation point relative to ionospheric irregularity. For one case of direct measurements of electric field in the place where the ionospheric irregularity was present, the sign of calculated disturbance corresponded to the observed one. High-resolution measurements on IRIS facility and meridional chain of the induction magnetometers are utilized for the accurate timing of the impact of solar wind irregularity on the magnetopause

Measurement of the neutron electric dipole moment by crystal diffraction

An experiment using a prototype setup to search for the neutron electric dipole moment by measuring spin-rotation in a non-centrosymmetric crystal (quartz) was carried out to investigate statistical sensitivity and systematic effects of the method. It has been demonstrated that the concept of the method works. The preliminary result of the experiment is $d_{\rm n}=(2.5\pm 6.5)\cdot 10^{-24}$ e$\cdot$cm. The experiment showed that an accuracy of $\sim 2.5\cdot 10^{-26}$ e$\cdot$cm can be obtained in 100 days data taking, using available quartz crystals and neutron beams.Comment: 13 pages, 4 figure

Morphological and structural features of the CdxPb1−xS films obtained by CBD from ethylenediamine-citrate bath

The calculating of ionic equilibria in the system «Pb(CH3COO)2 - CdCl2 - Na3C6H5O7 - ‎(NH3)2(CH2)2 - N2H4CS» allowed us to find conditions and concentration regions of PbS and CdS co-deposition. The determined conditions provided the CBD obtaining of CdxPb1−xS (0 ≤ x ≤ 0.033) substitutional solid solutions films with a cubic structure B1 (space group Fm ) with the grains preferred orientation (200). We established the evolution of the surface morphology of the synthesized films from cubic crystallites to hierarchical structure of globular aggregates by scanning electron microscopy. A quantitative analysis of diffraction patterns showed a decrease of microstrains in CdxPb1−xS films by a about factor of 3 with an increase of the cadmium chloride concentration in the reaction mixture from 0.005 to 0.14 mol/l. The excess of the cadmium content, established by EDX analysis, in the studied films as compared to its content in the solid solution is associated with the additional formation of the amorphous CdS phase up to 72 mol %.A Corrigendum is available for this article at https://doi.org/10.15826/chimtech.2021.8.2.12

Methodological approach to conducting a comparative analysis of economic systems at various stages of historical development

Comparative studies of economic systems have been gaining popularity in recent years. The existing methodology for comparing quantitative indicators of the functioning of the economies of different countries has a number of limitations. The presented article discusses methods for comparing the purchasing power of monetary units of the economies of different countries, and also analyzes the possibility of using them to carry out a comparative analysis of economic indicators and indicators of the development of industries in the USSR and modern Russia in order to develop proposals for improving the state economic and industrial policy. The analysis of methods of comparing the purchasing power of monetary units made it possible to substantiate the choice of approaches for comparing production, technological and financial and economic indicators of the development of industries in the USSR and the Russian Federation. Based on the selected approaches of comparing monetary units, the conversion coefficients for various historical periods were calculated: the USSR (from 1940 to 1990) and the Russian Federation (from 2000 to 2020)

A magneto-gravitational trap for precision studies of gravitational quantum states

Observation time is the key parameter for improving the precision of measurements of gravitational quantum states of particles levitating above a reflecting surface. We propose a new method of long confinement in such states of atoms, anti-atoms, neutrons and other particles possessing a magnetic moment. The Earth gravitational field and a reflecting mirror confine particles in the vertical direction. The magnetic field originating from electric current passing through a vertical wire confines particles in the radial direction. Under appropriate conditions, motions along these two directions are decoupled to a high degree. We estimate characteristic parameters of the problem, and list possible systematic effects that limit storage times due to the coupling of the two motions. In the limit of low particle velocities and magnetic fields, precise control of the particle motion and long storage times in the trap can provide ideal conditions for both gravitational, optical and hyperfine spectroscopy: for the sensitive verification of the equivalence principle for antihydrogen atoms; for increasing the accuracy of optical and hyperfine spectroscopy of atoms and antiatoms; for improving constraints on extra fundamental interactions from experiments with neutrons, atoms and antiatoms

SUSY approach to Pauli Hamiltonians with an axial symmetry

A two-dimensional Pauli Hamiltonian describing the interaction of a neutral spin-1/2 particle with a magnetic field having axial and second order symmetries, is considered. After separation of variables, the one-dimensional matrix Hamiltonian is analyzed from the point of view of supersymmetric quantum mechanics. Attention is paid to the discrete symmetries of the Hamiltonian and also to the Hamiltonian hierarchies generated by intertwining operators. The spectrum is studied by means of the associated matrix shape-invariance. The relation between the intertwining operators and the second order symmetries is established and the full set of ladder operators that complete the dynamical algebra is constructed.Comment: 18 pages, 3 figure