Physics of Atomic Nuclei最新文献

{"title":"Generation of the Resonant Magnetic Fields in the T-15MD Tokamak","authors":"P. V. Savrukhin,&nbsp;E. A. Shestakov,&nbsp;V. I. Tepikin","doi":"10.1134/S1063778825130113","DOIUrl":"10.1134/S1063778825130113","url":null,"abstract":"<p>Requirements for generation of the resonant magnetic fields in tokamaks for controlling magnetohydrodynamic (MHD) plasma perturbations, stabilizing edge localized modes (ELM), and suppressing accelerated electron beams are considered. A preliminary design of a system for generating external resonant magnetic fields on the T-15MD tokamak is considered. The design is based on a system of 48 multipole coils located inside a vacuum vessel (16 windings around the equatorial plane, 16 windings in the upper cone, and 16 windings in the lower cone) to create resonant magnetic fields with poloidal and toroidal harmonics <i>m</i> = 1–8, <i>n</i> = 1–4.</p>","PeriodicalId":728,"journal":{"name":"Physics of Atomic Nuclei","volume":"88 1 supplement","pages":"S13 - S20"},"PeriodicalIF":0.4,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Statistical Analysis of Similarity of Profiles of Plasma Parameters at Quasi-Stationary Stage of Discharges in Globus-M2 Tokamak","authors":"G. S. Kurskiev,&nbsp;P. A. Sdvizhenskii,&nbsp;N. S. Zhiltsov,&nbsp;E. E. Tkachenko,&nbsp;N. V. Teplova,&nbsp;G. A. Troshin,&nbsp;A. K. Kryzhanovsky,&nbsp;A. B. Kukushkin,&nbsp;A. V. Sokolov,&nbsp;V. V. Voloshinov","doi":"10.1134/S106377882513006X","DOIUrl":"10.1134/S106377882513006X","url":null,"abstract":"<p>The similarity of spatial profiles of electron temperature <i>T</i>_e and electron density <i>n</i>_e at the quasi-stationary stage of electric current in plasma in 21 discharges in the Globus-M2 tokamak have been statistically analyzed. The analysis is similar to that carried out earlier with JET tokamak data. The existence of universal profiles of <i>T</i>_e and <i>n</i>_e depending on the normalized minor radius of the plasma column ρ has been shown. The discharge universal profiles (DUPs) are obtained by dividing the space-time-dependent profile by the space-averaged value of this parameter in the region ρ ≤ ρ_max = 0.5–1 and subsequent averaging over time at the quasi-stationary stage of each discharge. The machine universal profiles (MUPs) are obtained by additional averaging over time of all discharges. It has been shown that, in all considered discharges, the time-averaged <span>({{{{tilde {sigma }}}}_{{{{T}_{{text{e}}}}}}})</span>, the relative root-mean-square deviations of the <i>T</i>_e profile from the DUP and MUP, at ρ_max = 0.8 on radii of ρ = 0.1–0.7 do not exceed 10%, and at ρ = 0.9, accuracy decreases. Similar values of spatially averaged <span>({{{{tilde {sigma }}}}_{{{{T}_{{text{e}}}}}}})</span> exceed 10% only at one of 136 time points of all considered discharges. A similar picture has been observed for <i>n</i>_e profiles. A comparison of the MUP for <i>T</i>_e in JET and Globus-M2 has shown some difference in profiles, maximal at small ρ. Using the SvF method of balanced identification, the accuracy of the representation of <i>T</i>_e(ρ, <i>t</i>) as the product of two functions of only one variable, time and coordinate, has been found. The results illustrate the high degree of plasma self-organization in tokamaks.</p>","PeriodicalId":728,"journal":{"name":"Physics of Atomic Nuclei","volume":"88 1 supplement","pages":"S29 - S40"},"PeriodicalIF":0.4,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142673","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling of the Sputtering Rate of the Tokamak First Wall by Atoms of Hydrogen Isotopes in the Near-Wall Plasma","authors":"R. I. Khusnutdinov,&nbsp;N. E. Efimov,&nbsp;I. A. Nikitin,&nbsp;Yu. M. Gasparyan,&nbsp;A. B. Kukushkin","doi":"10.1134/S1063778825130046","DOIUrl":"10.1134/S1063778825130046","url":null,"abstract":"<p>A method for calculating sputtering of the tokamak first wall by fast charge-exchange neutral atoms of hydrogen isotopes in the near-wall plasma has been proposed. The application of the method has been shown by the example of sputtering of the assumed first-wall materials under the near-wall plasma conditions in the ITER tokamak. Using the BM1D2V code based on the ballistic model of hydrogen recycling kinetics in the tokamak main vacuum chamber, the velocity distribution function (VDF) of neutral atoms and molecules of hydrogen isotopes in the near-wall plasma has been calculated. Using the calculated VDFs, the sputtering rate of beryllium, tungsten, and boron from the surface of the first wall of the tokamak vacuum chamber in a typical ITER divertor operating mode has been estimated. The reflection coefficients of atoms of hydrogen isotopes from the first wall used in the ballistic model and the sputtering coefficients have been calculated using the SDTrimSP code.</p>","PeriodicalId":728,"journal":{"name":"Physics of Atomic Nuclei","volume":"88 1 supplement","pages":"S101 - S111"},"PeriodicalIF":0.4,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142675","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anisotropy of the Critical Current in Technical Superconductors: Methods of Analysis and Application Examples","authors":"V. V. Guryev,&nbsp;I. V. Kulikov,&nbsp;S. V. Shavkin","doi":"10.1134/S1063778825130034","DOIUrl":"10.1134/S1063778825130034","url":null,"abstract":"<p>The study of critical current anisotropy with respect to the direction of the external magnetic field is fundamental for optimizing the design of superconductor-based devices, particularly magnetic systems in controlled fusion facilities. This article provides a concise critical overview of modern methods for analyzing the angular dependence of the critical current in technical superconductors, with a focus on second-generation high-temperature superconducting (HTS) tapes. These methods are grounded in three previously proposed models: scaling, vortex path, and anisotropic pinning. Experimental results of angular dependence studies for HTS-2 tapes with varying chemical compositions are presented. Several distinctive features are highlighted, including the nontrivial effect of rare earth element substitution in the HTS composition on the pinning landscape, peak asymmetry, and critical current dependence on the Lorentz force direction. The analytical methods discussed are then applied to the experimental data. The quality of model approximations was evaluated using the coefficient of determination, adjusted for the number of fitting parameters. The analysis reveals fundamental differences in the interpretation of features of angular dependences depending on the chosen model. It is concluded that no universal approach exists to reasonably interpret observed features while linking them to the defect structure of HTS materials. This highlights a significant gap in current understanding of superconducting electromagnetic behavior and underscores the need for further research.</p>","PeriodicalId":728,"journal":{"name":"Physics of Atomic Nuclei","volume":"88 1 supplement","pages":"S79 - S91"},"PeriodicalIF":0.4,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"TOREQ—A Code for Solving the Grad–Shafranov Equation in Plasma with a Fixed Boundary","authors":"Yu. V. Gott","doi":"10.1134/S1063778825130022","DOIUrl":"10.1134/S1063778825130022","url":null,"abstract":"<p>A simple TOREQ (Toroidal Equilibrium) code for solving the Grad–Shafranov equation, applicable for a tokamak with any aspect ratio, any (positive and negative) triangularity, any elongation with a fixed D-shaped or with X-point boundary, and with any arbitrary functions on the right-hand side of the equation has been described. The results of calculations of equilibrium parameters with published data have been compared.</p>","PeriodicalId":728,"journal":{"name":"Physics of Atomic Nuclei","volume":"88 1 supplement","pages":"S92 - S100"},"PeriodicalIF":0.4,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling of Stable Equilibrium Magnetic Configurations for the First Experiments on the Tokamak T-15MD","authors":"D. Yu. Sychugov,&nbsp;D. V. Ryzhakov,&nbsp;V. F. Andreev,&nbsp;A.V. Gorbunov,&nbsp;N. A. Kirneva,&nbsp;D. A. Kislov,&nbsp;G. E. Notkin,&nbsp;A. V. Sushkov,&nbsp;K. N. Tarasyan,&nbsp;D. A. Shelukhin,&nbsp;E. N. Khairutdinov","doi":"10.1134/S1063778825130125","DOIUrl":"10.1134/S1063778825130125","url":null,"abstract":"<p>Two experimental campaigns were carried out at the T-15MD tokamak in 2023. The main goal of the experiments was to obtain discharges with a plasma current in the range of hundreds of kiloamperes and a duration of about several seconds. To obtain equilibrium magnetic configurations and ensure stable discharge scenarios, a series of calculations using the TOKSСEN code was carried out before the start of the experiments and during the campaign. Taking into account the calculations carried out during the experiments, stable configurations of the plasma cord with a current of up to 250 kA and a duration of up to 2 s were realized.</p>","PeriodicalId":728,"journal":{"name":"Physics of Atomic Nuclei","volume":"88 1 supplement","pages":"S1 - S12"},"PeriodicalIF":0.4,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling of Electron Cyclotron Absorption of Injected Radiation in Plasma at the Initial Stage of Discharge in Tokamaks","authors":"P. V. Minashin,&nbsp;D. R. Filipenko,&nbsp;A. B. Kukushkin","doi":"10.1134/S1063778825130071","DOIUrl":"10.1134/S1063778825130071","url":null,"abstract":"<p>A new ray tracing code, Fast_mp_ECH_startup, for calculating the multipass electron cyclotron (EC) absorption of injected radiation in plasma at the initial stage of discharge in tokamaks has been presented. For conditions close to the initial stage of discharge in tokamak reactors, the EC absorption efficiency calculated by the new code has been compared with calculations using the ray-tracing code GENRAY and with calculations based on the model of isotropic and homogeneous mixing of the injected radiation after one or more reflections from the vacuum chamber wall.</p>","PeriodicalId":728,"journal":{"name":"Physics of Atomic Nuclei","volume":"88 1 supplement","pages":"S112 - S120"},"PeriodicalIF":0.4,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Heat Flux Testing of the Vertical Divertor Target under Simulated Separatrix Sweeping Conditions","authors":"R. V. Rulev,&nbsp;I. V. Mazul,&nbsp;P. Yu. Piskarev,&nbsp;V. E. Kuznetsov,&nbsp;V. V. Levichev,&nbsp;M. S. Kolesnik,&nbsp;V. V. Ruzanov,&nbsp;V. N. Tanchuk","doi":"10.1134/S1063778825130095","DOIUrl":"10.1134/S1063778825130095","url":null,"abstract":"<p>The problem of high heat fluxes on tokamak reactor divertor targets, which hinder the development of durable divertor targets with extended operational lifetimes, is considered. Potential approaches to enhance the allowable heat flux on the high-heat-flux components of the divertor are outlined. In order to verify the operability of one of the approaches, thermal cycling tests of the mockup were performed at the Tsefey-M facility. Thermal analyses carried out prior to the thermal cycling tests, as well as the experimental results themselves, are presented to enable a qualitative comparison. The method under study demonstrated its effectiveness, potentially enabling an increase in the permissible heat flux on the divertor up to 30 MW/m² or more.</p>","PeriodicalId":728,"journal":{"name":"Physics of Atomic Nuclei","volume":"88 1 supplement","pages":"S57 - S66"},"PeriodicalIF":0.4,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fiber-Optic Current Sensor Concept for the T-15MD Tokamak","authors":"G. A. Sarancha,&nbsp;A. S. Drozd,&nbsp;M. S. Kudashev,&nbsp;D. S. Sergeev","doi":"10.1134/S1063778825130101","DOIUrl":"10.1134/S1063778825130101","url":null,"abstract":"<p>Classic methods for plasma current measurement in tokamaks based on Faraday’s law of induction (Rogowski coil) or the Hall effect (Hall sensor) have a number of disadvantages that can be most acute in fusion reactor steady-state operating regimes (strong stray fields, operation in a long pulse with a constant plasma current). To ensure reliability of the measurements, the use of current sensors based on other physical principles may be required. Such a sensor is a fiber-optic current sensor (FOCS) based on the magneto-optic effect (Faraday effect). An analysis of international experience in FOCS application for plasma current measurements (JET, EAST, Tore-Supra tokamaks, etc.) was carried out in this work. Based on analysis, the concept of an improved FOCS measurement scheme for the T-15MD tokamak was proposed. The proposed FOCS reflective (double-pass) circuit, operating on the interferometer principle with probing at an intermediate frequency, will make it possible to carry out measurements over the entire designed range of plasma currents (up to 2 MA) with an error of 0.5 kA and a time resolution of 100 μs.</p>","PeriodicalId":728,"journal":{"name":"Physics of Atomic Nuclei","volume":"88 1 supplement","pages":"S21 - S28"},"PeriodicalIF":0.4,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142672","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Damage of the Tungsten Surface Layer under Irradiation by Steady-State Ion and Pulsed Beam-Plasma Helium Fluxes","authors":"I. V. Borovitskaya,&nbsp;V. N. Pimenov,&nbsp;S. N. Korshunov,&nbsp;A. N. Mansurova,&nbsp;S. A. Maslyaev,&nbsp;A. S. Demin,&nbsp;E. V. Morozov,&nbsp;N. A. Epifanov,&nbsp;A. B. Mikhailova,&nbsp;S. V. Latyshev,&nbsp;G. G. Bondarenko,&nbsp;A. I. Gaidar,&nbsp;E. V. Matveev,&nbsp;I. S. Monakhov","doi":"10.1134/S1063778825130010","DOIUrl":"10.1134/S1063778825130010","url":null,"abstract":"<p>Comparative studies of tungsten surface damageability under irradiation with steady-state helium ion fluxes and pulsed helium ion and helium plasma fluxes in the ion-beam accelerator (ILU) and in the Vikhr Plasma Focus (PF) installation have been carried out. The parameters of irradiation with steady-state He⁺ ion fluxes in the ILU: helium ion energy of 30 keV; fluences of 1.0 × 10¹⁸ and 2.0 × 10¹⁸ cm^–2; and target temperature during irradiation not exceeding ~500 K. For irradiation with pulsed fluxes of helium ions and helium plasma in the Vikhr PF installation, the samples were placed in the cathode zone of the Vikhr PF chamber at a distance of 2, 4, and 6 cm from the anode. Parameters of irradiation of samples in the Vikhr PF: duration of ion and plasma exposure of 10–30 and 50–200 ns, respectively; power density of plasma in the range of ∼10⁷–10⁹ W/cm² and ions in the range of ~10⁹–10¹⁰ W/cm²; number of pulses <i>N</i> = 5, 15, and 30; helium ion energy of ~100 keV; and plasma temperature of ~1 keV. Under irradiation with steady-state He⁺ ion fluxes with a fluence of 10¹⁸ cm^–2, formation of blisters with peripheral rupture of caps characteristic of brittle materials is observed. An increase in the irradiation fluence by a factor of two leads to a change in the mechanism of surface failure; i.e., exfoliation of layers (flaking) is observed. During irradiation of samples in the Vikhr PF installation, melting of the surface layer occurs, resulting in a wavy surface relief with the appearance of cracks and craters, i.e., traces of helium gas release and unopened blisters. The sizes of craters are ∼1–2 µm, which is comparable to the dimensions of blisters observed after He⁺ ion implantation in the ILU accelerator. Numerical modeling of the impact of a fast helium ion beam on tungsten in the Vikhr PF installation has been performed. Using methods of X-ray diffraction analysis, the following effects are observed: a decrease in lattice parameters under all modes of ion and plasma flux exposure; varying degrees of changes in the size of the coherent scattering region (CSR) and the magnitude of lattice microstrain and texture. A decrease in the microhardness of tungsten samples after treatment with helium plasma and He⁺ ions in the Vikhr PF installation is detected, which may result from the influence of two competing factors: annealing of defects under intense thermal loads (reduces <i>H</i>_μ ) and thermal stresses arising during the crystallization and cooling of the melted surface layer (increases <i>H</i>_μ ). The mechanisms of the observed phenomena are discussed.</p>","PeriodicalId":728,"journal":{"name":"Physics of Atomic Nuclei","volume":"88 1 supplement","pages":"S67 - S78"},"PeriodicalIF":0.4,"publicationDate":"2025-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145142674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}