2304-9782, 2618-8686, 2405-7223 13 2 2020 1-177

RAR RUS 9-16 Herzen State Pedagogical University of Russia Gorokhovatskiy Yuriy yurig@fromru.com Herzen State Pedagogical University of Russia Demidova Natalya demidov_evg@mail.ru Herzen State Pedagogical University of Russia Temnov Dmitry tde@herzen.spb.ru Electric charge relaxation in the polyethylene with mineral inclusions of diatomite The paper considers methods for increasing stability of polyethylene’s electret state by adding diatomite particles to its composition. The results of analyzing the IR spectra, the involved materials’ temporal and temperature stability are presented. Mechanisms for improving the stability of the composite polyethylene’s electret state are discussed. 10.18721/JPM.13201 538.9 electret state polyethylene diatomite thermoactivation spectroscopy https://physmath.spbstu.ru/article/2020.48.1/ 1_9-16_13(2)2020.pdf

RAR RUS 17-26 Ryazan State University named for S.A.Yesenin Tregulov Vadim trww@yandex.ru The efficiency of solar energy conversion by the CdS/por-Si/p-Si heterostructure: the dopant effect In this paper, the effect of the distribution profile of the doping acceptor impurity concentration in the base region of the CdS/por-Si/p-Si heterostructure on the efficiency of solar energy conversion parameters has been studied. It was established that the solar energy conversion efficiency depended on the degree of a doping acceptor impurity depletion of the near-surface p-Si layer in the por-Si/p-Si heterojunction. The distribution profile of the impurity concentration in this space is formed during the growth of a porous silicon layer. This profile is controlled through changing the technological parameters of the process of a porous film growing: the current density and the duration time of the electrochemical etching. A gain in the conversion efficiency of solar energy was explained by an increase in the penetration depth of the electric field into the base region due to formation of a certain type of the impurity concentration distribution profile. In the final, this profile promotes the rapid carry-away of charge carriers generated by the light from the base region. This carry-away occurs before the carrier recombination moment involving traps. 10.18721/JPM.13202 538.91 porous silicon heterojunction photovoltaic converter solar cell capacitance–voltage characteristic https://physmath.spbstu.ru/article/2020.48.2/ 2_17-26_13(2)2020.pdf

RAR RUS 27-40 Peter the Great St. Petersburg Polytechnic University Aleksander Levchenya levchenya@yandex.ru Peter the Great St. Petersburg Polytechnic University Trunova Seraphima seraphimatr@yandex.ru 0000-0002-6308-733X Peter the Great St. Petersburg Polytechnic University Kolesnik Elizaveta kolesnik_ev@mail.ru Assessment of RANS turbulence models capabilities based on computational results for free convection developing near a suddenly heated vertical plate The results of testing several RANS turbulence models in solving a problem of free air convection temporal development near the surface of a suddenly heated infinite vertical plate have been presented in the paper. The solution results with the use of the different models were compared with the literature data obtained by direct numerical simulation. Numerical solutions were carried out using the four models, two of them based on the isotropic turbulent viscosity concept and the rest ones involved solving the transport equations of the Reynolds stress tensor components. The flow and heat transfer characteristics for different stages of boundary layer development, from laminar to turbulent, were analyzed. Based on a comparison with the literature data on direct numerical simulation, conclusions about the predictive capabilities of the RANS models considered were drawn. 10.18721/JPM.13203 532.517 convection RANS simulation time-developing direct numerical simulation boundary layer https://physmath.spbstu.ru/article/2020.48.3/ 3_27-40_13(2)2020.pdf

RAR RUS 41-52 Peter the Great St. Petersburg Polytechnic University Petrichenko Mikhail fonpetrich@mail.ru

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

Musorina Tatiana flamingo-93@mail.ru Fractional differentiation operation in the Fourier boundary problems We use the algebra of unbounded differentiation t operators acting on the ring of differentiable functions. The analytical representation of the fractional degree of the t operator is used to construct the resolvents of three boundary problems for the Fourier equation. Periodic solutions of limiting Fourier problems in the algebra of differentiation operators coincide with classical solutions. The t+2 extension is a continuous spectrum of the Fourier transform and allows us to obtain exact solutions of three limit problems for a domain of any dimension d > 1. 10.18721/JPM.13204 530.1 differential equation Abel–Liouville formula ring of operators inverse operator carrier distribution https://physmath.spbstu.ru/article/2020.48.4/ 4_41-52_13(2)2020.pdf

RAR RUS 53-71 0000-0003-0985-5964 Institute for Analytical Instrumentation of the RAS Berdnikov Alexander asberd@yandex.ru 0000-0003-3514-8577 Peter the Great St. Petersburg Polytechnic University Solovyev Konstantin k-solovyev@mail.ru

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

0000-0002-6162-9481 Peter the Great St. Petersburg Polytechnic University Krasnova Nadezhda n.k.krasnova@mail.ru Chains of fundamental mutually homogeneous functions with a common real eigenvalue This work continues our studies in properties of the mutually homogeneous functions (MHF) being a generalization of Euler homogeneous functions. MHF can be used in the synthesis of electric and magnetic fields for electron systems and ion-optical ones with special properties. A chain of functions corresponding to multiple real eigenvalues of the matrix of basic functional relations for MHF has been considered. Functional relations answering such functions were derived. General formulas for the solutions of the obtained functional relations were derived. The obtained functions were shown to be a refinement of the associated homogeneous functions introduced by Gel’fand. Typical differential and integral properties of the obtained functions were investigated, and a generalization of the Euler theorem was proved (Euler criterion) for differentiable functions. 10.18721/JPM.13205 517.51; 517.28; 517.983; 537.213, 537.8 functional equation homogeneous function associated homogeneous function mutually homogeneous functions https://physmath.spbstu.ru/article/2020.48.5/ 5_53-71_13(2)2020.pdf

RAR RUS 72-88 0000-0003-0985-5964 Institute for Analytical Instrumentation of the RAS Berdnikov Alexander asberd@yandex.ru 0000-0003-3514-8577 Peter the Great St. Petersburg Polytechnic University Solovyev Konstantin k-solovyev@mail.ru

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

0000-0002-6162-9481 Peter the Great St. Petersburg Polytechnic University Krasnova Nadezhda n.k.krasnova@mail.ru General formulas for chains of fundamental mutually homogeneous functions with a common pair of complex conjugate eigenvalues This work continues our studies in properties of mutually homogeneous functions (MHFs), being a generalization of Euler homogeneous functions and can be used in the synthesis of electric and magnetic fields of electron and ion-optical systems with special properties. MHFs corresponding to multiple pairs of complex conjugate eigenvalues of the matrix of basic functional equations have been considered in addition to MHF chains corresponding to multiple real eigenvalues of the matrix of basic functional relations. Functional equations characterizing such functions were deduced, general formulas for the MHFs with complex conjugate multiple eigenvalues were derived. 10.18721/JPM.13206 517.51; 517.28; 517.983; 537.213, 537.8 functional equation homogeneous function associated homogeneous function mutually homogeneous functions https://physmath.spbstu.ru/article/2020.48.6/ 6_72-88_13(2)2020.pdf

RAR RUS 88-98 Institute for High Energy Physics named by A.A.Logunov of NRC «Kurchatov Institute» Maisheev Vladimir maisheev@ihep.ru Institute for High Energy Physics named by A.A.Logunov of NRC «Kurchatov Institute» Sandomirskiy Yury Yury.Sandomirskiy@ihep.ru Institute for High Energy Physics named by A.A.Logunov of NRC «Kurchatov Institute» Chesnokov Mikhail Michail.Chesnokov@ihep.ru Institute for High Energy Physics named by A.A.Logunov of NRC «Kurchatov Institute» Chesnokov Yury chesnokov@ihep.ru Institute for High Energy Physics named by A.A.Logunov of NRC «Kurchatov Institute» Yanovich Andrey yanovich@ihep.ru Devices for steering particle beams in the accelerators based on crystals curved by scratching the grooves on the surface An interesting method of bending silicon crystal plates by scratching the grooves on the surface mechanically has been presented in the paper. This method appears to have considerable promise for both the U70 accelerator at the Institute for High Energy Physics and the devices at the Large Hadron Collider (LHC). Using the method mentioned above, specific devices were made: a crystalline undulator for 3 GeV positrons, short crystalline deflectors for extraction of 70 GeV proton beam from the U70 accelerator, and multistrip crystals for collimating the 6500 GeV proton beam into the LHC. 10.18721/JPM.13207 621.384.663 Large Hadron Collider beam collimation crystal undulator multistrip crystal https://physmath.spbstu.ru/article/2020.48.7/ 7_89-98_13(2)2020.pdf

RAR RUS 99-115 Peter the Great St. Petersburg Polytechnic University Tsybin Oleg otsybin@rphf.spbstu.ru Peter the Great St. Petersburg Polytechnic University Makarov Sergey makarov@cee.spbstu.ru Peter the Great St. Petersburg Polytechnic University Dyubo Dmitry doobinator@rambler.ru Military Space Academy named after A.F. Mozhaysky Kuleshov Yuri vka@mil.ru Military Space Academy named after A.F. Mozhaysky Goncharov Pavel vka@mil.ru Military Space Academy named after A.F. Mozhaysky Martynov Viktor vka@mil.ru Military Space Academy named after A.F. Mozhaysky Shunevich Nikolay vka@mil.ru An electrically powered ion accelerator with contact ionization for perspective electrically powered thrusters A number of characteristics of ionic and ion-plasma accelerators laboratory samples designed for electrically powered spacecraft propulsion have experimentally been studied. A large-sized vacuum chamber (2.4 m3, 10–3 Pa) made at the Military Space Academy named after A.F. Mozhaysky provided the necessary physical and technological processes, methods and means of measurement, parameters and operation modes of the ionic accelerators with contact ionization. The samples’ design features, physical processes and operating parameters were theoretically analyzed, including the use of computer simulation. The implemented and tested measuring methods, technologies and ion-physical laboratory samples’ characteristics were found to correspond to the tasks of developing the promising electrically powered spacecraft propulsion. 10.18721/JPM.13208 621.455.4; 621.455.34 vacuum chamber experimental studies computer simulation ionization ion beam ion accelerator electrically powered spacecraft propulsion https://physmath.spbstu.ru/article/2020.48.8/ 8_99-115_13(2)2020.pdf

RAR RUS 116-125 St.Petersburg National Research University of Information Technologies, Mechanics and Optics Koreshev Sergey koreshev@list.ru St. Petersburg National Research University of Information Technologies, Mechanics and Optics Smorodinov Denis smorodinov.denis@gmail.com St. Petersburg National Research University of Information Technologies, Mechanics and Optics Frolova Marina marrain6@yandex.ru St. Petersburg National Research University of Information Technologies, Mechanics and Optics Starovoitov Sergei s.starovoitov95@gmail.com Imaging properties of computer-generated holograms: the phase distribution effect in the object’s space In the paper, the influence of phase distribution over the objects’ space on resolution and depth of field of computer-generated holograms has been investigated. The study was carried out through mathematical simulation of real physical processes of synthesis and reconstruction of binary transparent holograms. The possibility of a significant increase (up to several times) in the resolution and depth of field of the reconstructed image because of using phase-shift masks was found. Moreover, this increase was achieved due to representation of the object wave in hologram synthesis as a superposition of object waves emanating light from two identical objects located at different, strictly fixed distances from the hologram synthesis plane. 10.18721/JPM.13209 535.417; 535.317; 778.38 synthesized hologram binarization threshold processing depth of field phase mask https://physmath.spbstu.ru/article/2020.48.9/ 9_116-125_13(2)2020.pdf

RAR RUS 126-141 Concern CSRI “Elektropribor” Kostromitin Aleksey kostromitin.aleksei@yandex.ru 0000-0001-5988-1429 Peter the Great St. Petersburg Polytechnic University Liokumovich Leonid leonid@spbstu.ru Skliarov Philip 0000-0001-8448-2024 Peter the Great St. Petersburg Polytechnic University Kotov Oleg kotov@rphf.spbstu.ru The fiber-optic interferometric schemes with multiplexed sensitive elements: an analysis of output optical power level A concept for calculation of element parameters and analyzing the output power in the fiberoptic interferometric schemes with time-division multiplexing of the sensitive elements (TDM) has been put forward in the paper. The calculation procedure of element parameters allows ensuring the equality of the optical power from all multiplexed sensitive elements, as well as evaluating the effect of deviation of the optical scheme parameters from the calculated ones. Using two optical schemes as an example, the implementation of this calculation concept, the sequence of obtaining mathematical expressions, and examples of calculation results were presented. The proposed calculation method could be successfully applied in the design of interferometric meters with multiplexing of fiber-optic sensitive elements. 10.18721/JPM.13210 535.3, 535-15, 535.417 fiber-optic sensor fiber-optic splitter optical power optical loss time-division multiplexing https://physmath.spbstu.ru/article/2020.48.10/ 10_126-141_13(2)2020.pdf

RAR RUS 142-151 Peter the Great St. Petersburg Polytechnic University Borisov Vladislav vl-borisof@yandex.ru

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

0000-0003-0309-5917 Peter the Great St. Petersburg Polytechnic University Berdnikov Yaroslav berdnikov@spbstu.ru Peter the Great St. Petersburg Polytechnic University Berdnikov Alexander alexber@phmf.spbstu.ru

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

0000-0002-3395-0454 Peter the Great St. Petersburg Polytechnic University Kotov Dmitry dmitriy.kotov@gmail.com Peter the Great St. Petersburg Polytechnic University Mitrankov Yuriy mitrankovy@gmail.com

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

Production of K*-mesons in the copper-gold nuclei collisionsat √(s_NN) = 200 GeV This paper presents invariant transverse momentum spectra and nuclear modification factors of K*(892)-mesons measured in the Cu + Au collisions at √(s_NN ) = 200 GeV. The measurements were performed in five centrality bins in the range of transverse momentum from 2.00 to 5.75 GeV/c in the PHENIX experiment at the RHIC. Nuclear modification factors were compared with previously obtained PHENIX data in Cu + Cu collisions at √(s_NN ) = 200 GeV. The nuclear modification factors of K*-mesons in Cu + Cu and Cu + Au collisions at the same values of a number of participants Npartwere found to have similar values (within uncertainties). 539.126.3 10.18721/JPM.13211 quark gluon plasma jet quenching heavy ion collision strangeness nuclear modification factor https://physmath.spbstu.ru/article/2020.48.11/ 11_142-151_13(2)2020.pdf

RAR RUS 152-159 Peter the Great St. Petersburg Polytechnic University Mitrankova Mariia mashalario@gmail.com 0000-0003-0309-5917 Peter the Great St. Petersburg Polytechnic University Berdnikov Yaroslav berdnikov@spbstu.ru Peter the Great St. Petersburg Polytechnic University Berdnikov Alexander alexber@phmf.spbstu.ru

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

Peter the Great St. Petersburg Polytechnic University Mitrankov Yuriy mitrankovy@gmail.com

Russia, 195251, St.Petersburg, Polytechnicheskaya, 29

0000-0002-3395-0454 Peter the Great St. Petersburg Polytechnic University Kotov Dmitry dmitriy.kotov@gmail.com Measurement of φ-meson’s nuclear modificatiion factors in the collisions of proton beams with aluminum nuclei at an energy of 200 GeV The φ-mesons production in the relativistic collisions of proton beams with aluminum nuclei (p + Al, small system) at √(s_NN) energy of 200 GeV has been studied. The PHENIX experiment was carried out at the RHIC. The φ-mesons’ invariant transverse momentum spectra and their nuclear modification factors were measured in four centrality bins of the range of transverse momentum (%): 0 – 20, 20 – 40, 40 – 72, 0 – 72. The obtained results were compared with similar data on the π0-mesons production. The experimental data analysis led to the conclusion that the φ-mesons’ nuclear modification factors were equal to one (within the measurement uncertainties) over all available ranges of centrality and transverse momenta. The findings of the work testified that quark-gluon plasma did not produce in the performed collisions. 10.18721/JPM.13212 539.12 quark-gluon plasma cold nuclear matter effect,nuclear modification factor relativistic ion collision https://physmath.spbstu.ru/article/2020.48.12/ 12_152-159_13(2)2020.pdf

RAR RUS 160-174 0000-0003-0376-4463 Institute for Problems of Mechanical Engineering RAS Frolova Ksenia fkp@ipme.ru Determination of the effective Young's modulus of medium with microstructure typical for hydrogen degradation The paper aims at calculation of the effective elastic properties of metals with a microstructure typical for hydrogen-enhanced degradation. For the purpose of this study, we use the Maxwell homogenization scheme and explicit expression for compliance contribution tensor to determine the overall Young's moduli. The model introduces oblate spheroids to describe intergranular microcracks and spheres to describe pores. Within the frame of the paper, we consider random orientations of the microcracks, certain preferential orientation accompanied by random scatter with the scattering parameter and random orientations of the spheroids’ axes in the same plane. The dependences of the effective Young's moduli on the porosity and aspect ratio of the spheroid have been studied. 10.18721/JPM.13213 539.3 effective Young's modulus Maxwell homogenization scheme hydrogen degradation spheroidal inhomogeneity https://physmath.spbstu.ru/article/2020.48.13/ 13_160-174_13(2)2020.pdf