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Defined are socio-cultural features of integration of immigrants into host community at border regions. The article presents results of the author’s sociological research, organized in Belgorod and Voronezh regions in form of interviewing foreign migrants. Emphasized is, that border regions have special specifics, that require development of comprehensive state policy in relation to integration of migrants. Also the main problems of adaptation and integration of foreign labor migrants in the border areas are identified. Such are in particular the low level of trust of migrants in relation to state and municipal authorities. The study analyzes regional characteristics of foreign labor migration in border regions of Russia. It is noted, that presence of social ties with the host community is a significant factor in adaptation of migrants into new environment. Performed diagnostics of practice of integration of immigrants into border region made possible to identify the main problems that hinder processes of optimization of integration policy in relation to foreign labor migrants. One of the main directions is that, that development of state policy regarding integration of migrants into the host community is activation of new subjects of support for integration and adaptation, namely public organizations and the third sector.

Hot ion mode was recently achieved at the Globus-M2 spherical tokamak when the toroidal magnetic field was as high as 0.9 T and plasma current 0.35 MA. The injection of two neutral beams with a total power of 0.7 MW and an energy of 30 keV into a plasma with major radius 0.36 m and minor radius 0.22 m (aspect ratio 1.6) made it possible to heat the plasma ions up to 4 keV, while electron density in the plasma center was as high as 8 × 1019 m−3. The achievement of high temperatures became possible due to the good thermal insulation of the plasma.

A new model for interaction between the internal reconnections caused by sawtooth and the edge-localized modes (ELM) was presented. The experimental evidence of the coupling between sawtooth crash and ELM events were observed in the Globus-M and Globus-M2 tokamaks. The numerical analysis of magnetic equilibrium showed that internal reconnections can induce the excess current density near the separatrix during the several hundreds of μs. The excess current destabilizes the peeling-ballooning (PB) instability. The PB stability analysis showed that the penetration depth of the induced current should be in the range of ψ norm = 0.8–0.95 to trigger the instability.

In the H-mode discharges with the neutral beam heating (NBI) in the Globus-M tokamak the sawtooth oscillations are triggering the edge localised modes (ELM) onset. The triggered ELMs have the magnetic oscillation precursor less than 0.2 ms before the onset with the typical island rotation frequency. The paper discussing the peeling-ballooning (P-B) destabilisation caused by the current density profile broadening due to partial reconnection.

In the final Globus-M experimental campaign B tor and I p were raised by 25% up to 0.5 T and 250 kA, respectively, expanding available range of experimental parameters. In these experiments an overall improvement in plasma performance was observed, plasma total stored energy and neutron rate increased significantly. The energy confinement time dependence on B tor and n e was close to linear. L-H transition threshold was 5–10 times higher than threshold predicted by the scaling. Despite the small plasma-wall distance, the level of radiation losses in the main plasma volume was relatively small and decreased as B tor rised. An increase in B tor and I p led to a decrease in the sawtooth-induced losses. While a rise in the plasma current led to a decrease of fast ion losses per TAE burst at the same amplitude; frequency of bursts and their amplitude increased. Doppler backscattering, applied to study TAE localization for the first time, revealed that TAE fluctuations are localized in the region of normalized minor radii ρ = 0.5–0.75. A new movable 9-pin head probe provided data, necessary for power decay length scaling investigation. Significant power decay length contraction, stronger than predicted by Eich’s scaling, was observed.

The Globus-M2 spherical tokamak is the considerably upgraded Globus-M facility. Its technical parameters were increased as much as possible to achieve the promising range of physical parameters (sub-fusion temperatures and collisionality of much less than unity). These parameters will be achieved in a compact magnetic configuration similar to that of the Globus-M tokamak, the plasma current and toroidal magnetic field amounting to 0.5 MA and 1 T, respectively. The demand to increase the magnetic field and plasma current in the Globus-M2 resulted in the need for a complete redesign of the electromagnetic system because the plasma equilibrium requirements have changed and the mechanical and thermal loads have considerably increased as compared to the Globus-M. The vacuum vessel and the in-vessel components of the new Globus-M2 tokamak remain the same. Power supplies were upgraded to provide the required currents in the toroidal field coil and the central solenoid. The Globus-M2 tokamak was build up and preliminary tests were carried out. New auxiliary heating systems and diagnostics were developed and installed to be used in future experiments. Fist plasma was achieved at the Globus-M2 in April 2018.

Analysis of stability of the peeling-ballooning modes in the edge plasma of the Globus-M tokamak is presented. Studies were performed using the ideal 3D MHD code written in the BOUT++ framework. The edge localized modes which are frequently observed in the Globus-M plasma could be described using MHD theory. It was found that the parameters of the Globus-M edge plasma are in the range of stability for the peeling-ballooning modes. The instability modes with a toroidal number of n = 12 and typical distances between filaments of approximately ~12 cm were found to be the most unstable. This statement agrees with the Doppler backscattering measurements. It was also considered whether the plasma in the Globus-M2 tokamak will be stable against the PB instability.

A diagnostic system for plasma radiated power tomography on Globus-M was upgraded with a new linear array based on silicon photodiodes. The hardware of the diagnostic system based on a 256-channel tangential matrix array and a 24-channel linear array is described. The algorithm for 2D tomographic reconstruction of plasma emissivity is presented. It uses the Tikhonov regularization method and anisotropic diffusion functional as a side constraint. Simulated plasma emissivity profiles were used to test and assess the capabilities of the developed algorithm. Data analysis was carried out in ohmic and neutral beam heated discharges to demonstrate the performance of the tomography diagnostic in plasmas with different parameters. The presented results illustrate the proper functioning of the tomography system that allowed to reveal and study various plasma phenomena, including magnetohydrodynamic mode.

The Globus-M spherical tokamak has demonstrated practically all of the project objectives during the 15-year period of operation. The main factor limiting further progress in plasma performance is a relatively low toroidal magnetic field. The maximum toroidal magnetic field achieved on Globus-M was 0.4 T with the exception of a limited number of shots with 0.55 T, which led to damage of the toroidal field coil in 2002. The increase of the magnetic field up to 1.0 T together with the plasma current up to 0.5 MA will result in the significant enhancement of the operating parameters in the upgraded Globus-M2 machine. The experimental program will be focused on plasma heating and non-inductive current drive and will contribute to the creation of a physical and technological base for the compact fusion neutron source development. In the article a brief overview of the physical background for the machine upgrade is outlined. The current status of the project implementation is described. First experimental results on moderate magnetic field increase from 0.4 T up to 0.5 T in the existing Globus-M machine are discussed. The improvement of plasma confinement as well as enhancement of efficiency of the beam driven current is observed.