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Recent experimental data from space-based instruments of the DAMPE and CALET collaborations have shown that the energy spectrum of protons has a new feature, a break in the $\sim 10$ TeV region. In this energy range, the spectrum index of the observed particles varies from $-2.6$ to $-2.9$. The purpose of this work is to establish the local sources's position and age that determine this break, the index of the proton generation spectrum in them, as well as the astrophysical interpretation of the results obtained in the DAMPE and CALET experiments. Within the framework of the model of nonclassical diffusion of cosmic rays developed by the authors, which has break due to the propagation of particles in a sharply inhomogeneous (fractal type) galactic medium, it is shown that break in this energy range is formed by tevatron located at a distance of $\sim 120$ pc from the Earth. These source, whose age is $\sim 5 \cdot 10^5$ years, generate particles with a spectrum index $\sim 2.7$. The power-law behavior of the proton spectrum before and after the break, soft spectrum of particles generation in the source, first obtained in the DAMPE and CALET experiments, should be considered as an indication of the need to revise the standard paradigm accepted today about the sources of cosmic rays, mechanisms of particle acceleration in them and particles propagation in the Galaxy., Comment: 13 pages, 5 figures, 1 table, The 4th International Symposium on Cosmic Rays and Astrophysics (ISCRA-2023)

The paper discusses an approach that made it possible to estimate the distance to the nearest pevatrons, which form a knee in the spectrum of the cosmic ray nucleon component of about $4$ PeV. It is based on the spectra of nucleons and electrons obtained by the authors in the framework of the superdiffusion model of nonclassical cosmic rays diffusion, which have a knee, on the assumption that nucleons and electrons are accelerated by the same type sources and their propagation in an inhomogeneous turbulent galactic medium is characterized by the same diffusion coefficient, and also on the knee in the spectrum of the electronic component in the region of $0.9$ TeV, established in the DAMPE experiment. It is shown that pevatrons, which form a knee in the spectrum of the cosmic ray nucleon component of about $4$ PeV, are located at distances of the order of $0.75$ kpc from the Earth., Comment: 12 pages, 3 figures, 2 tables, The 4th International Symposium on Cosmic Rays and Astrophysics (ISCRA-2023)

The physical motivations, present status, main results in study of cosmic rays and in the field of gamma-ray astronomy as well future plans of the TAIGA-1 (Tunka Advanced Instrument for cosmic ray physics and Gamma Astronomy) project are presented. The TAIGA observatory addresses ground-based gamma-ray astronomy and astroparticle physics at energies from a few TeV to several PeV, as well as cosmic ray physics from 100 TeV to several EeV. The pilot TAIGA-1 complex is located in the Tunka valley, ~50 km west from the southern tip of the lake Baikal., Comment: Submission to SciPost Phys. Proc., 10 pages, 2 figures

The corrected dependence of the mean depth of the EAS maximum $X_{max}$ on the energy was obtained from the data of the Tunka-133 array for 7 years and the TAIGA-HiSCORE array for 2 years. The parameter $\langle\ln A\rangle$, characterizing the mean mass compositon was derived from these results. The differential energy spectrum of primary cosmic rays in the energy range of $2\cdot 10^{14}$ - $2\cdot 10^{16}$\,eV was reconstructed using the new parameter $Q_{100}$ the Cherenkov light flux at the core distance 100 m.}, Comment: 6 pages, 3 figures, Submitted to SciPost Phys.Proc

The Tunka-Grande experiment is a scintillation array with about 0.5 sq.km sensitive area at Tunka Valley, Siberia, for measuring charged particles and muons in extensive air showers (EASs). Tunka-Grande is optimized for cosmic ray studies in the energy range 10 PeV to about 1 EeV, where exploring the composition is of fundamental importance for understanding the transition from galactic to extragalactic origin of cosmic rays. This paper attempts to provide a synopsis of the current results of the experiment. In particular, the reconstruction of the all-particle energy spectrum in the range of 10 PeV to 1 EeV based on experimental data from four observation seasons is presented., Comment: 7 pages, 3 figures, submission to SciPost Phys. Proc

A wide-angle Cerenkov array TAIGA-HiSCORE (FOV $\sim$0.6 sr), was originally created as a part of TAIGA installation for high-energy gamma-ray astronomy and cosmic ray physics. Array now consist on nearly 100 optical stations on the area of 1 km$^2$. Due to high accuracy and stability ($\sim$1 ns) of time synchronization of the optical stations the accuracy of EAS arrival direction reconstruction is reached 0.1$^\mathrm{o}$. It was proven that the array can also be used to search for nanosecond events of the optical range. The report discusses the method of searching for optical transients using the HiSCORE array and demonstrates its performance on a real example of detecting signals from an artificial Earth satellite. The search for this short flares in the HiSCORE data of the winter season 2018--2019 is carried out. One candidate for double repeater has been detected, but the estimated probability of random simulation of such a transient by background EAS events is not less than 10%, which does not allow us to say that the detected candidate corresponds to a real astrophysical transient. An upper bound on the frequency of optical spikes with flux density of more than $10^{-4} \mathrm{erg/s/cm}^2$ and a duration of more than 5\,ns is established as $\sim 2 \times 10^{-3}$ events/sr/hour., Comment: 15 pages, 6 figures, reported at the conference ISCRA-2021, Accepted for publication in Physics of Atomic Nuclei

Different compaction processes of the nanosized granular system, which is a prototype of an alumina nanopowder, are studied by the granular dynamics method. For all processes: compaction curves ''density vs. pressure'' of the powder compact are calculated, the elastic and the plastic parts are extracted from the total deformation, the body elastic moduli are determined within the isotropic solid approximation. The inadequacy of the isotropy approximation is established. The nanopowder yield surface is constructed in the space of stress tensor invariants. The inapplicability of the traditional associated flow rule for description of oxide nanopowders compaction processes is revealed. An alternative flow rule is suggested., Comment: 17 pages, 10 figures, 41 references

Recent balloon-borne and satellite experiments have established new features in the behavior of the spectra of cosmic rays. An analysis of all the data showed that hardening of most abundant primary cosmic ray nuclei spectra with increasing rigidity is observed in $>200$ GV region. At the same time, rigidity dependencies of secondary cosmic rays are distinctly different. The AMS-02 data show that above 200 GV the secondary cosmic rays Li, Be, B harden more than the primary He, C, O. In this paper we discuss a new scenario that self-consistently describes these new features of the cosmic ray spectra. We demonstrate that the measured by the AMS-02 changes in the slope of the cosmic ray spectra caused by the transition from the contribution of multiple distant Galactic sources, including the nuclear interactions of the particles accelerated by these sources with an interstellar medium during their wandering in the Galaxy, to the contribution of mainly local ones. We also found that the spectral universality is observed at rigidity $R> 10^5$ GV., Comment: 8 pages, 4 figures, 26th Extended European Cosmic Ray Symposium

The experimental EXCITOR setup for obtaining the intense electron beams of picosecond duration is presented in this work. Cathodes of tungsten, graphite, copper and samarium of the same shape were used in these experiments. The interelectrode gap varied from 0.5 to 6 mm. Interferometric technique to detect anode rear side displacement was used. The time evolution of the displacement and speed of the rear side of copper anode of 0.1 and 3.0 mm thickness was experimentally obtained. Simulation of the space-time characteristics evolution of the anode material is presented., Comment: Submitted to 6th International Congress Energy Fluxes and Radiation Effects (EFRE 2018), September 16-21, 2018, Tomsk, Russia. To be published in Journal of Physics: Conference Series, 10 pages, 11 figures

The paper concerns the nanopowder high-speed, $10^4$ - $10^9$ s${}^{-1}$, compaction processes modeling by a two-dimensional granular dynamics method. Nanoparticles interaction, in addition to known contact laws, included dispersive attraction, formation of a strong interparticle bonding (powder agglomeration) as well as the forces caused by viscous stresses in the contact region. For different densification rates, the "pressure vs. density" curves (densification curves) were calculated. Relaxation of the stresses after the compression stage was analyzed as well. The densification curves analysis allowed us to suggest the dependence of compaction pressure as a function of strain rate. It was found that in contrast to the plastic flow of metals, where the yield strength is proportional to the logarithm of the strain rate, the power-law dependence of applied pressure on the strain rate as $p\propto v^{1/4}$ was established for the modeled nanosized powders., Comment: 11 pages, 4 figures, 1 table, 21 references

The possibility for a self-consistent description of all the basic features of the observed cosmic ray spectra and primary composition variations in the energy range of $10^{15}\div 10^{20}$ eV within the Galactic origin scenario is examined. We assume the existence of Galactic sources that accelerate particles up to $\sim 3\cdot 10^{18}Z$ eV and take into account a highly inhomogeneous (fractal-like) distribution of matter and magnetic fields in the Galaxy that leads to extremely large free paths of particles ("L\'{e}vy flights"), along with an overwhelming contribution to the cosmic ray fluxes observed above $\sim 10^{18}$ eV from particles reaching the Solar System without scattering. Our scenario was refined on the basis of recent experimental results on primary mass composition. Model predictions, which could be verified with the improved high-precision measurements in the nearest future are discussed., Comment: 5 pages, 2 figures, 19th International Symposium on Very High Energy Cosmic Ray Interactions (22-27 August 2016). Moscow, Russia. P.N. Lebedev Physical Institute of the Russian Academy of Sciences (LPI RAS)

On the basis of the scaling approach and CORSIKA simulations data the radial scale factor of lateral distribution of electrons in extensive air showers is confirmed as potentially effective primary mass estimator, and its sensitivity to hadronic interaction model is investigated. It is shown that improved composition results both on average and event-by-event basis can be achieved taking into account the universality property of air shower development expressed by the relation between radial scale factor and longitudinal age parameter. The enhancements of such a theoretically motivated tool for the unbiased cosmic ray composition deduction in a wide primary energy range from (multi-)hybrid air shower measurements of nearest future are discussed., Comment: 4 pages, 3 figures, 19th International Symposium on Very High Energy Cosmic Ray Interactions (22 - 27 August 2016). Moscow, Russia. P.N.Lebedev Physical Institute of the Russian Academy of Sciences (LPI RAS)

Electron and phonon spectra dynamics, as well as features of structural transitions and melting of sodium under pressure within range 0 to 100 GPa are investigated. Electron and phonon spectra of crystal sodium are calculated ab initio within the density functional theory by means of the LMTART-7 software package (Savrasov-Savrasov: 1992; Savrasov: 1996; Savrasov: 2004), allowing the fully potential method of linear muffin-tin orbitals. Using the Lindemann measure and the calculated phonon spectra the theoretical values of melting points corresponding to the experimental data (Gregoryanz, et al: 2005; Gregoryanz, et al: 2008) are obtained. Features of electron and phonon spectra dynamics in the melting curve maximum vicinity and within cI2->cI4 structural transition range are discussed., Comment: 9 pages, 6 figures, contribution to the Proceedings of the International Congress on "Energy Flows and Radiation Effects", Tomsk, Russia, October 2-7, 2016 (to be published in Journal of Physics: Conference Series)

We offer a metal model suitable for the description of fast electrophysical processes in conductors under influence of powerful electronic and laser radiation of femto- and picosecond duration, and also high-voltage electromagnetic pulses with picosecond front and duration less than 1 ns. The obtained dynamic equations for metal in approximation of one quasineutral liquid are in agreement with the equations received by other authors formerly. New wide-range expressions for the electronic conduction in strong electromagnetic fields are obtained and analyzed., Comment: 12 pages, no figures, contribution to the Proceedings of XXXI International Conference on "Equation of State for Matter", Elbrus, Russia, March 1-6, 2016 (to be published in Journal of Physics: Conference Series)

The conditions for the flux growth of new Mn-Ni oxyborates with the ludwigite structure are reported. Magnetic measurement data for the samples with nickel and manganese predominance are presented. Diamagnetic anomalies of the antiferromagnetic phases are established and analyzed in the framework of a model comprising two antiferromagnetically interacting subsystems, each being antiferromagnetically ordered., Comment: 11 figures, 3 tables

We report on the crystallographic structure of the layered compound Pb3Mn7O15. Previous analysis based on laboratory X-ray data at room temperature gave contradictory results in terms of the description of the unit cell. Motivated by recent magnetic bulk measurements of this system, we re-investigated the chemical structure with high-resolution synchrotron powder diffraction at temperatures between 15 K and 295 K. Our results show that the crystal structure of stoichiometric Pb3Mn7O15 has a pronounced 2-dimensional character and can be described in the orthorhombic space group Pnma., Comment: 6 pages, 4 figures, 2 tables

The present paper is a concluding part of the series [N.B. Volkov and A.M. Iskoldsky: 1; 2; [1], [2]]. Here on the basis of the results of the above papers the experiments on the electric explosion in conductors have been discussed and the mechanism of "hot" plasma spots formation which was repeatedly observed in the experiments on a plasma focus, z-pinches, vacuum sparks and electric explosion of microwires has been proposed. To realize this mechanism, the formation of sausage-type instabilities is not necessary. Moreover, the possibility of hot spots formation in a liquid metal (in the model under discussion, the plasma-like medium is assumed incompressible and the local kinetic transport coefficients - constant) has been shown. The latter is of great interest for understanding the mechanism of initiation and operation of vacuum arc cathode spots and also for the explanation to the phenomenon of explosive electron emission which is widely employed in applied physics., Comment: LaTeX, 10 PostScript figures, (E-mail: ami@ami.e-burg.su). Accepted for publication in J.Phys.A: Math. and Gen. (1993-1994)

In the present paper which is a sequel to [N.B. Volkov and A.M. Iskoldsky The dynamics of vortex structures and states of current: 1;[1]], the dynamics of non-equilibrium phase transitions and states of current in electrophysical systems providing an external circuit and a nonlinear element the model of which has been developed in [1] (in the development of the model local kinetic transport coefficients were assumed to be constant), has been analyzed and simulated. A non-equilibrium phase transition has been shown to be induced by large-scale hydrodynamic fluctuations (vortex structures). Critical exponents of the amplitude singular behavior (the order parameters) for three types of circuits have been determined. Non-equilibrium phase transitions induced by external harmonic noise with a random or a determined phase have been studied. The detuning between an external noise frequency and natural frequencies of a nonlinear element determined by large-scale hydrodynamic fluctuations have been shown to give rise to random oscillations, which are typical of a strange attractor. When the frequencies coincide, a limit cycle appears in the system, which is characterized by the fact that the phase trajectory does not fill the phase space completely., Comment: LaTeX, 23 PostScript figures, (E-mail: ami@ami.e-burg.su)

A set of equations according to which the conducting medium consists of two fluids - laminar and vortex, has been obtained in the present paper by transforming MHD equations. In a similar way, an electronic fluid is assumed to consist of a laminar and a vortex fluid. This system allows one to study the formation and the dynamics of large-scale hydrodynamic fluctuations. From this model a model of a non-equilibrium phase transition belonging to a class of the Lorenz-type models has been developed [Lorenz E N 1963 J. Atmos. Sci. {\bf 20} 130]. Vortex structures resulting in the increase in an effective resistance of the conducting medium and the interruption of current have been shown to appear even at constant transport coefficients in a laminar electronic fluid. Critical exponents of the parameters of an order (amplitudes), which for a direct current coincide with the critical exponents in the Lorenz model, have been found. A spatial scale of the structure described by the theory is in good agreement with experiment. A further evolution of vortex structures has been shown to occur by splitting the spatial scale. A similarity, according to which the following sequence of splitting takes place: {\({k_0}{\rightarrow}{k_1}=0.5{k_0}{\rightarrow} {k_2}=2{k_0}{\rightarrow}{k_3}=2{k_2}\)}, etc. has been hypothesized., Comment: LaTeX, 3 PostScript figures,(E-mail: ami@ami.e-burg.su)

At present, there are a great number of radio meteor, ionosphere and rocket observation data for the altitude range of 80 to 100 km which indicate the existence of large scale circulation systems in the mesopause to low thermosphere range which change regularly with season and latitude. But the existing observation network and observation programs are not optimal for revealing the main factors forming the circulation mode at these altitudes. A generalized optimum monitoring mathematical model is offered for consideration. The model input data are distribution density, response function, individual measurement root mean square uncertainty and detection effectiveness function. The model makes it possible to obtain the observation distribution density, the minimal possible dispersion and optimized system effectiveness.

Kinetic model of oxygen exchange in man during muscular work