Low-energy Flux Research Articles

Deciphering competing interactions of Kitaev–Heisenberg-Γ system in clusters: I. Static properties

Recently, the Kitaev-Heisenberg-Γ system has been used to explore various aspects of Kitaev spin liquid physics. Here, we consider a few small clusters of up to twelve sites and study them in detail to unravel many interesting findings due to the competition between all possible signs and various magnitudes of these interactions under the influence of an external magnetic field. When Heisenberg interaction is taken anti-ferromagnetic, one obtains plateaus in correlation functions where, surprisingly, the exact groundstate reduces to the eigenstate of Heisenberg interaction as well. On the other hand, for ferromagnetic Heisenberg interaction, its competition with Kitaev interaction results in non-monotonicity in the correlation functions. We discuss, in detail, the competing effects on low energy spectrum, flux operator, magnetization, susceptibility, and specific heat. Finally, we discuss how our findings could be helpful to explain some of the recent experimental and theoretical findings in materials with Kitaev interactions.

CYGν\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\ u $$\\end{document}S: detecting solar neutrinos with directional gas time projection chambers

Cygnus is a proposed global network of large-scale gas time projection chambers (TPCs) with the capability of directionally detecting nuclear and electron recoils at ≳\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gtrsim $$\\end{document}keV energies. The primary focus of Cygnus so far has been the detection of dark matter, with directional sensitivity providing a means of circumventing the so-called “neutrino fog”. However, the excellent background rejection and electron/nuclear recoil discrimination provided by the 3-dimensional reconstruction of ionisation tracks could turn the solar neutrino background into an interesting signal in its own right. For example, directionality would facilitate the simultaneous spectroscopy of multiple different flux sources. Here, we evaluate the possibility of measuring solar neutrinos using the same network of gas TPCs built from 10 m3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^3$$\\end{document}-scale modules operating under conditions that enable simultaneous sensitivity to both dark matter and neutrinos. We focus in particular on electron recoils, which provide access to low-energy neutrino fluxes like pp, pep, 7\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^7$$\\end{document}Be, and CNO. An appreciable event rate is already detectable in experiments consisting of a single 10 m3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^3$$\\end{document} module, assuming standard fill gases such as CF4\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$_4$$\\end{document} mixed with helium at atmospheric pressure. With total volumes around 1000 m3\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$^3$$\\end{document} or higher, the TPC network could be complementary to dedicated neutrino observatories, whilst entering the dark-matter neutrino fog via the nuclear recoil channel. We evaluate the required directional performance and background conditions to observe, discriminate, and perform spectroscopy on neutrino events. We find that, under reasonable projections for planned technology that will enable 10–30-degree angular resolution and ∼10\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\sim 10$$\\end{document}% fractional energy resolution, Cygnus could be a competitive directional neutrino experiment.

МГД-волны в области предфронта межпланетных ударных волн 6 и 7 сентября 2017 г.

We analyze strong space weather disturbances during first ten days of September 2017, using the geomagnetic Dst index, parameters of normals to interplanetary shock fronts, direct measurements of interplanetary magnetic field, solar wind, and cosmic ray parameters. By applying spectral analysis methods to interplanetary medium data, we analyze MHD waves at the pre-front of two interplanetary shocks responsible for geomagnetic disturbances on September 6 and 7, 2017. The main results are as follows: the contribution of three branches of MHD waves (Alfvén, fast and slow magnetosonic) to the observed spectrum of the interplanetary magnetic field modulus has been established. We have confirmed the conclusion that the generation of Alfvén waves and fast magnetosonic waves is due to the presence of low-energy proton fluxes (Ep~1 MeV) at the pre-front of interplanetary shocks. We have also discovered a predominant contribution of slow magnetosonic waves to the observed spectrum of the interplanetary magnetic field modulus, but its reason is yet unknown. It is noted that different orientations of the normals to the interplanetary shock fronts and to the direction of the interplanetary magnetic field average vector on spacecraft located fairly close to each other may indicate waviness of the shock front structure.

MHD waves at the pre-front of interplanetary shocks on September 6 and 7, 2017

We analyze strong space weather disturbances during first ten days of September 2017, using the geomagnetic Dst index, parameters of normals to interplanetary shock fronts, direct measurements of interplanetary magnetic field, solar wind, and cosmic ray parameters. By applying spectral analysis methods to interplanetary medium data, we analyze MHD waves at the pre-front of two interplanetary shocks responsible for geomagnetic disturbances on September 6 and 7, 2017. The main results are as follows: the contribution of three branches of MHD waves (Alfvén, fast and slow magnetosonic) to the observed spectrum of the interplanetary magnetic field modulus has been established. We have confirmed the conclusion that the generation of Alfvén waves and fast magnetosonic waves is due to the presence of low-energy proton fluxes (Ep~1 MeV) at the pre-front of interplanetary shocks. We have also discovered a predominant contribution of slow magnetosonic waves to the observed spectrum of the interplanetary magnetic field modulus, but its reason is yet unknown. It is noted that different orientations of the normals to the interplanetary shock fronts and to the direction of the interplanetary magnetic field average vector on spacecraft located fairly close to each other may indicate waviness of the shock front structure.

Constraining the low-energy cosmic ray flux in the center molecular zone from MeV nuclear deexcitation line observations

Constraining the low-energy cosmic ray flux in the center molecular zone from MeV nuclear deexcitation line observations

Plasma sources sputtering nanoscale contaminants with low-energy ion flux on front-end mirrors in ITER optical diagnostics

New plasma sources are proposed to clean optical mirrors in diagnostic instruments of the ITER experiment considering RF discharges operating at low pressures (1–10 Pa) in inert gases. There are nearly twenty optical diagnostics where the front-end optical mirrors may require plasma cleaning. The mirrors vary in size and would need up to 400 W in the discharge to form ion fluxes capable of removing Be- and W-containing contaminants to restore the optical performance with tolerable damage to the mirror. The plasma sources suggested to clean contaminants include a vacuum matching circuit placed close to the mirror and a quarter wavelength band stop notch filter when mirror water cooling is needed. Long-term operation stability and cleaning homogeneity may employ a driving frequency variation to tune the circuit and a phase shift for RF voltages to clean two mirrors simultaneously. In this paper, the plasma sources based on 40 MHz RF discharge to clean first mirrors are studied experimentally for two ITER optical instruments: the Edge Thomson Scattering and the Visible Spectroscopy Reference System. Frequency tuning and phase shifting are studied in realistic configurations prototyping diagnostic port plug geometries.

Féeton (B-L gauge boson) dark matter for the 511-keV gamma-ray excess and the prediction of low-energy neutrino flux* *Supported by the Talent Scientific Start-Up Project of China, the Natural Science Foundation of China (12175134, 12375101, 12090060, 12090064, 12247141), the SJTU Double First Class start-up fund(WF220442604), and the World Premier International Research Center Initiative (WPI Initiative), MEXT, Japan

The féeton is the gauge boson of the gauge theory. If the gauge coupling constant is extremely small, the féeton becomes a candidate for dark matter. We show that its decay to a pair of an electron and a positron explains the observed Galactic 511-keV gamma-ray excess in a consistent manner. This féeton dark matter decays mainly into pairs neutrino and anti-neutrino. Future low-energy experiments with improved directional capability will enable capturing these neutrino signals. The seesaw-motivated parameter space predicts a relatively short féeton lifetime that is comparable to the current cosmological constraint.

Accretion Flow Properties of EXO 1846-031 during Its Multi-peaked Outburst after Long Quiescence

We study the recent outburst of the black hole candidate EXO 1846-031, which went into an outburst in 2019 after almost 34 yr in quiescence. We use archival data from the Swift/XRT, MAXI/GSC, NICER/XTI, and NuSTAR/FPM satellites/instruments to study the evolution of the spectral and temporal properties of the source during the outburst. The low-energy (2–10 keV) X-ray flux of the outburst shows multiple peaks, making it a multipeak outburst. Evolving type-C quasi-periodic oscillations are observed in the NICER data in the hard, hard-intermediate, and soft-intermediate states. We use the physical two-component advective flow (TCAF) model to analyze the combined spectra of multiple satellite instruments. According to the TCAF model, the accreting matter is divided into Keplerian and sub-Keplerian parts, and the variation in the observed spectra in different spectral states arises out of the variable contributions of these two types of accreting matter in the total accretion rate. Studying the evolution of the accretion rates and other properties of the accretion flow obtained from the spectral analysis, we show that the multiple peaks in the outburst flux arise out of the variable supply of accreting matter from the pile-up radius. We determine the probable mass of the black hole to be from the spectral analysis with the TCAF model. We also estimate the viscous timescale of the source in this outburst to be ∼8 days from the peak difference of the Keplerian and sub-Keplerian mass-accretion rates.

Taxonomic Re-Classification and Expansion of the Phylum Chloroflexota Based on over 5000 Genomes and Metagenome-Assembled Genomes.

The phylum Chloroflexota (formerly Chloroflexi) encompasses metabolically diverse bacteria that often have high prevalence in terrestrial and aquatic habitats, some even with biotechnological application. However, there is substantial disagreement in public databases which lineage should be considered a member of the phylum and at what taxonomic level. Here, we addressed these issues through extensive phylogenomic analyses. The analyses were based on a collection of >5000 Chloroflexota genomes and metagenome-assembled genomes (MAGs) from public databases, novel environmental sites, as well as newly generated MAGs from publicly available sequence reads via an improved binning approach incorporating covariance information. Based on calculated relative evolutionary divergence, we propose that Candidatus Dormibacterota should be listed as a class (i.e., Ca. Dormibacteria) within Chloroflexota together with the classes Anaerolineae, Chloroflexia, Dehalococcoidia, Ktedonobacteria, Ca. Limnocylindria, Thermomicrobia, and two other classes containing only uncultured members. All other Chloroflexota lineages previously listed at the class rank appear to be rather orders or families in the Anaerolineae and Dehalococcoidia, which contain the vast majority of genomes and exhibited the strongest phylogenetic radiation within the phylum. Furthermore, the study suggests that a common ecophysiological capability of members of the phylum is to successfully cope with low energy fluxes.

Higher energy flux may improve short-term appetite control in adolescents with obesity: the NEXT study.

Recent evidence suggests better appetite control in states of high-energy flux (HEF) in adults and lean children. Nevertheless, it is unknown whether this extends to youth with obesity. This study compares the effects of low, moderate or HEF on short-term appetitive control in adolescents with obesity. Sixteen adolescents with obesity (12-16 years, Tanner stages 3-5, 11 females) randomly completed three conditions: (i) low-energy flux (LEF); (ii) moderate energy flux (MEF; + 250 kcal) and (iii) HEF (HEF; + 500 kcal). Energy flux was achieved in MEF and HEF through elevated energy intake (EI) and concomitant increase in energy expenditure using cycling exercise (65 % VO2peak). Ad libitum EI, macronutrient intake and relative EI were assessed at dinner, subjective appetite sensations taken at regular intervals and food reward measured before dinner. Ad libitum EI at dinner was greater in LEF compared with HEF (P = 0·008), and relative EI (REI) was higher in LEF compared with MEF (P = 0·003) and HEF (P < 0·001). The absolute consumption of carbohydrates was lower in LEF compared with MEF (P = 0·047) and HEF (P < 0·001). Total AUC for hunger and desire to eat was lower in HEF compared with LEF (P < 0·001) and MEF (P = 0·038). Total AUC for prospective food consumption was lower on HEF compared with LEF (P = 0·004). Food choice sweet bias was higher in HEF (P = 0·005) compared with LEF. To conclude, increasing energy flux may improve short-term appetite control in adolescents with obesity.

BGO quenching effect on spectral measurements of cosmic-ray nuclei in DAMPE experiment

The Dark Matter Particle Explorer (DAMPE) is a satellite-borne detector designed to measure high energy cosmic-rays and γ-rays. As a key sub-detector of DAMPE, the Bismuth Germanium Oxide (BGO) imaging calorimeter is utilized to measure the particle energy with a high resolution. The nonlinear fluorescence response of BGO for large ionization energy deposition, known as the quenching effect, results in an under-estimate of the energy measurement for cosmic-ray nuclei. In this paper, various models are employed to characterize the BGO quenching factors obtained from the experimental data of DAMPE. Applying the proper quenching model in the detector simulation process, we investigate the tuned energy responses for various nuclei and compare the results based on two different simulation softwares, i.e. GEANT4 and FLUKA. The BGO quenching effect results in a decrease of the measured energy by approximately 2.5% (5.7%) for carbon (iron) at ∼10 GeV/n and <1% above 1 TeV/n, respectively. Accordingly, the correction of the BGO quenching effect leads to an increase of the low-energy flux measurement of cosmic-ray nuclei.

Plasma low-energy ion flux induced vertical graphene synthesis

Vertical graphene (VG) is a promising material for energy-storage, sensor, and electronic applications, owing to excellent structural, mechanical, and electrical properties. An existing method for synthesizing VG is plasma-enhanced chemical vapor deposition under high plasma ion-energy interaction on carbon surface. However, since this method can cause substrate damage, device performance degradation, and internal defects in VG, a new synthesis method using low-ion-energy is required. Accordingly, it is necessary to understand how the plasma low-ion energy contributes to the nucleation and growth of VG by interaction with the surface, but the reported studies are limited to the high-ion-energy region. Here, we report on the effects of low-energy ion flux in plasma-induced growth of vertical graphene and found the key plasma parameter for the VG growth and nucleation in a low-ion-energy environment and successfully controlled the nucleation of VG. VG deposition and plasma parameter measurements were performed in a radiofrequency inductively coupled plasma. In the low-energy region, the growth rate and nucleation of VG depended strongly on ion density, and insufficient ion flux formed highly disordered carbon. Based on these findings, VG nucleation was controlled by tailoring the ion energy and density under conditions where disordered carbon was formed.

Diffusion-assisted growth of periodic patterns on metal surfaces

Periodic patterns formed on various solid surfaces could seriously affect the properties of materials. Understanding the underlying mechanism is a key step to apply and control pattern formation in many fields. In this work, periodic patterns induced by low-energy plasma exposures on tungsten surfaces are observed and related new formation mechanisms are developed. Results from experiments and computer simulations demonstrate that atom diffusion accelerated by low energy and high flux exposures is the dominant mechanism for pattern formation. Furthermore, a similar pattern formation has been confirmed by plasma exposure experiments on molybdenum. Based on this mechanism, patterns with controllable shape have been successfully prepared on tungsten surface by adjusting plasma exposure parameters, which may provide a new understanding of pattern formation and related surface damage in tungsten induced by plasma exposures.

Microstructural evolution of Ti2ZrHfV0.5Mo0.2 refractory multi-principal alloy under low-energy, high-flux He ion irradiation

The irradiation response of refractory multi-principal element alloys (RMPEAs) has gained increasing attention for the potential applications in future fusion devices. In controlled fusion reactors, plasma-facing materials have to suffer continuous low-energy high flux helium (He) ion irradiations. During high flux He irradiation, vacancy-interstitial pairs can be generated through trap mutation mechanism even without cascade collision. To simplify the model, Ti2ZrHfV0.5Mo0.2 RMPEA was irradiated with 50 eV He+ (less than the minimum He displacement energy of the alloy EdTi = 67 eV) under 1200 K to various fluences of 5 × 1024 - 1 × 1026 ions/m2, and the microstructural evolution was investigated. In the irradiated RMPEA, the intense sputtering of Ti, the growth and degradation of fuzz mainly composed of Zr, Hf elements on the surface, as well as the formation of V, Mo enriched band and high density large He cavities in the subsurface layer were observed. Although the sputtering threshold energy for He of V is similar to that of Ti (ETi = 24 eV, EV = 29 eV), V showed anomalous enrichment in the subsurface layer. Moreover, unlike the W fuzz growth process, the adatoms used to form fuzz in Ti2ZrHfV0.5Mo0.2 were derived from the Zr, Hf atoms diffusing through the vacancy-solute exchange mechanism, rather than from the atoms formed by the loop-punching mechanism. The anomalous enrichment of V atoms and the different fuzz growth mechanism were attributed to (i) different migration rates for different species of atoms in the alloy under vacancy diffusion mechanism and (ii) the formation of AB2 (A = Ti, Zr, Hf; B = V, Mo) phase blocking the continued formation of prismatic dislocation loops mainly composed of V and Mo.

Enhancements of relativistic electron flux at geostationary orbit during high-intensity, long-duration, continuous AE activity (HILDCAA) from 2015 to 2017

This work characterizes the enhancements of relativistic electron flux (MeV) in the geostationary orbit (GEO) in High Intensity, Long Duration, Continuous AE Activity (HILDCAA) occurred during declining phase of solar cycle 24. We employed the relativistic electron (0.8 - 2.0 MeV) flux and low-energy electron (40 - 130 keV) flux measured by GOES-13 and POES satellites, respectively. Typically, the relativistic electron flux increases, while the low-energy electron flux decreases in the long recovery phase of moderate storms. The enhancements of E > 0.8 MeV and > 2.0 MeV occurred promptly and ∼1.0 day after the HILDCAA onset, respectively. A case study of short HILDCAA events shows that low solar wind dynamic pressure and long-lasting high amplitude Alfvén waves are efficient triggers of the relativistic electron enhancement at GEO. Large convection from magnetic reconnection in HILDCAA would induce substorms that injected more seed electrons for the acceleration. The peaks of the E > 2.0 MeV flux are more delayed than of the E > 0.8 MeV. After the onset of short- and prolonged-period HILDCAA, the peak flux of E > 0.8 MeV occurred about 2 and 4 days, respectively, and of E > 2.0 MeV occurred about 2 and 5 days, respectively.

Terrestrial-origin skyshine at sea level

Low-energy continuous gamma radiation with a maximum energy distribution at ∼70 keV reaches the Earth's surface from the upper hemisphere. In addition to components resulting from cosmic-origin low-energy gamma radiation, there is also a prominent contribution arising from gamma photons emitted by environmental radionuclides, which are backscattered by air above ground (commonly referred as “skyshine” radiation). Since both components are covering the same energy region of gamma radiation (mainly 30 keV–350 keV), it is not simple to determine the separate contributions of each radiation component to the total gamma flux. The efficient way to solve this long-standing problem is to study the backscattering of gamma radiation on the atmospheric air by Monte Carlo simulations. In this work, the simulations were performed in order to obtain air-backscattered spectra, as well as gamma photon fluxes which can be expected for specified activity concentrations of natural radionuclides (40K, 226Ra, 232Th) distributed in the ground. The simulation results were compared with experimental measurements of low-energy photon flux in the open area from the upper hemisphere. Furthermore, the influence of height above ground and distance from the shore on the skyshine intensity reduction is explored.

A Carbon Nanodot Based Near-Infrared Photosensitizer with a Protein-Ruthenium Shell for Low-Power Photodynamic Applications.

Near-infrared (NIR) light-activated photosensitization represents an encouraging therapeutic method in photodynamic therapy, especially for deep tissue penetration. In this context, two-photon activation, i.e., utilization of photons with relatively low energy but high photon flux for populating a virtual intermediate state leading to an excited state, is attractive. This concept would be highly advantageous in photodynamic therapy due to its minimal side effects. Herein, we propose that the combination of plasma protein serum albumin (HSA) containing several Ru complexes and NIR two-photon excitable carbon nanodots (Cdots), termed HSA-Ru-Cdots, provides several attractive features for enhancing singlet oxygen formation within the mitochondria of cancer cells stimulated by two-photon excitation in the NIR region. HSA-Ru-Cdot features biocompatibility, water solubility, and photostability as well as uptake into cancer cells with an endosomal release, which is an essential feature for subcellular targeting of mitochondria. The NIR two-photon excitation induced visible emission of the Cdots allows fluorescence resonance energy transfer (FRET) to excite the metal-to-ligand charge transfer of the Ru moiety, and fluorescence-lifetime imaging microscopy (FLIM) has been applied to demonstrate FRET within the cells. The NIR two-photon excitation is indirectly transferred to the Ru complexes, which leads to the production of singlet oxygen within the mitochondria of cancer cells. Consequently, we observe the destruction of filamentous mitochondrial structures into spheroid aggregates within various cancer cell lines. Cell death is induced by the long-wavelength NIR light irradiation at 810 nm with a low power density (7 mW/cm2), which could be attractive for phototherapy applications where deeper tissue penetration is crucial.

Charged Particle Fluxes Associated With CALIPSO Low Laser Energy Shots

The cloud-aerosol lidar and infrared pathfinder satellite observation (CALIPSO) mission was launched on 28 April 2006 into a 705-km Sun-synchronous orbit. At launch, the lidar laser canisters were filled with dry air at 130 kPa. The redundant canister pressure has dropped during the mission, reaching 7.6 kPa by late December 2021. Starting on June 23, 2016, individual laser shots started to exhibit anomalously low energies in regions of enhanced energetic charged particle fluxes. Small at first (< 1 mJ), drops in laser energy up to 61 mJ have been observed. This study determines the energetic charged particle populations associated spatially with low laser energy shots and the degree to which time variations in the low laser energy shots can be explained by time variations in the energetic charged particle fluxes. Particle observations from the NOAA-19 medium energy proton and electron detector (MEPED) are traced down magnetic field lines to estimate the fluxes at CALIPSO altitudes that are associated with individual low-energy shots. Predictions of the stability of particle bounce and drift motions in the geomagnetic field are used to sort low-energy shots and fluxes into different radiation belt regions. While most of the low-energy shots occur in the inner belt, there are clear spatial associations with outer belt electrons and with galactic cosmic rays (GCRs). As canister pressure has decreased, GCRs and electrons have become more effective in causing larger laser energy drops.

Evolution of bubble in tungsten irradiated by deuterium of low energy and high flux by molecular dynamics simulations

Using molecular dynamics simulations, the Tersoff-potential was used to investigate the evolution of deuterium (D) bubbles in tungsten (W). This work documents the entire evolution process of D bubbles: formation, growth and burst. The effects of flux, temperature and incident energy of D on the evolution and position of D bubbles were discussed. Temperature and flux together affect the time required for D bubble formation, and energy has a significant effect on depth. At 300 K, single-crystal tungsten surfaces (001), (110), (111), and (112) were bombarded by D atoms with 80 eV energy and 6.24 × 1028 m−2s−1 flux. Although all D bubbles go through three stages, the pressure, volume, and the ratio of (D in D2)/D inside bubbles can tell the difference between the four surfaces. Under the same simulation conditions, the evolution of D bubbles under a surface with a higher crystal face density was found to be harder.

INSTITUTIONALIZATION OF THE TRANSITION TO THE USE OF ALTERNATIVE SOURCES OF ENERGY

The consumption of traditional energy resources by the world economy leads to their catastrophic reduction and severe environmental consequences. In addition, there are a number of alternative means of energy replenishment, which are inexhaustible sources of energy: air, solar, geothermal energy, energy of orbital motion of the Earth (gravity), and energy derived from them. With traditional energy sources, they are able to provide energy to the world economy. Institutionalization processes have embraced the social development of global and national economies. It is important not only to cover alternative energy sources, but also to study the processes of institutionalization of the transition to them, improving the institutional system, institutions and institutions for the use of alternative energy sources. Multiple and diverse studies of alternative energy sources provide large-scale development. However, insufficient development of institutional issues, processes of institutionalization of the transition to the use of alternative energy sources are becoming a deterrent. Goal. The aim of the article is to develop scientifically sound proposals for the institutionalization of the transition to the use of alternative energy sources. Method. Various research methods are used: theoretical and empirical, fundamental and applied. Results. The rapid depletion of traditional energy resources and the constant increase in their price with increasing energy needs due to economic development and the evolution of people's lifestyles lead to the creation of alternative energy sources. The advantages of alternative energy sources are: renewable, widespread in most of their species, using some low operating costs, environmental friendliness. The negative qualities of using alternative energy sources include: low energy flux density, which forces manufacturers to use large areas of power plants; instability of energy production over time; high cost of using alternative energy sources. Institutionalization of the economy (generally) is a process of formation of formal institutions that limit the behavior of economic entities and generate a number of agreements, rules of the game, stereotypes of behavior, traditions. Institutionalization aims to improve the quality of life. The most important factor in justifying the institutionalization of the use of alternative energy sources is the need to address issues that directly affect the development and use of alternative energy sources. Scientific novelty. The study highlights problems that significantly reduce the use of alternative energy sources. Therefore, scientifically sound proposals for the institutionalization of the transition to the use of alternative energy sources: organizational, financial, methodological1, educational decisions. Practical significance. The practical significance of the study lies in the possibility of using developed scientifically sound proposals in the process of planning the country's energy strategy, sectoral programs for the development of energy generation from alternative sources, planning the work of industrial consumers, producers of energy from alternative sources.