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Bulletin of the Russian Academy of Sciences: Physics最新文献

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Study of Processes at the Delay Stage of a Subnanosecond Atmospheric Pressure Discharge Developing with the Participation of Runaway Electrons 亚纳秒大气压力放电延迟阶段的过程研究--失控电子的参与
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2025-03-18 DOI: 10.1134/S1062873824710511
S. N. Ivanov, V. V. Lisenkov
{"title":"Study of Processes at the Delay Stage of a Subnanosecond Atmospheric Pressure Discharge Developing with the Participation of Runaway Electrons","authors":"S. N. Ivanov,&nbsp;V. V. Lisenkov","doi":"10.1134/S1062873824710511","DOIUrl":"10.1134/S1062873824710511","url":null,"abstract":"<p>The modeling of the development of an electron avalanche initiated by an electron emitted from a micropoint on a cathode in the form of a cone 3 μm high is carried out. The avalanche development took place in nitrogen at atmospheric pressure in a uniform electric field with a strength of <i>E</i> = 680 kV/cm. That is, under conditions when <i>E</i> is much greater than the critical electric field strength <i>E</i><sub>cr</sub> required for the transition of electrons to the continuous acceleration mode according to the classical runaway criterion. The analysis was based on the experimentally obtained voltage waveforms on the discharge gas gap. Spatial distributions of electrons in the avalanche at different stages of its development and electron energy distribution functions for different numbers of electrons in the avalanche were obtained. It is shown that by the time when the number of electrons in the avalanche is in the range of 10<sup>3</sup>–10<sup>4</sup>, the maximum energy of electrons begins to exceed 1 keV, which can be interpreted as the beginning of the transition of individual electrons from the avalanche to the runaway mode. The beginning of the exit of individual fast electrons from the avalanche can be seen in the spatial distribution of electrons. Then these fast electrons, moving to the anode, ionize the gas and leave behind a narrow track of slow electrons. It is shown that the part of runaway electrons is very small and amounts to ~10<sup>–5</sup> of the total number of electrons. Thus, the gas discharge plasma mainly consists of slow electrons despite the fact that <i>E</i> significantly exceeds <i>E</i><sub>cr</sub>.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 4 supplement","pages":"S495 - S500"},"PeriodicalIF":0.48,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Features of Electron Emission in Pulsed Forevacuum Plasma-Cathode Electron Beam Sources Based on a Cathodic Arc and a Constricted Arc Discharge
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2025-03-18 DOI: 10.1134/S1062873824710523
A. V. Kazakov, E. M. Oks, N. A. Panchenko
{"title":"Features of Electron Emission in Pulsed Forevacuum Plasma-Cathode Electron Beam Sources Based on a Cathodic Arc and a Constricted Arc Discharge","authors":"A. V. Kazakov,&nbsp;E. M. Oks,&nbsp;N. A. Panchenko","doi":"10.1134/S1062873824710523","DOIUrl":"10.1134/S1062873824710523","url":null,"abstract":"<p>Investigation of features of electron emission in pulsed forevacuum plasma-cathode electron sources based on a cathodic arc and a constricted arc discharge operating at gas pressure of 4–30 Pa (N<sub>2</sub>, O<sub>2</sub>, Ar, He) are presented. In these forevacuum electron sources, operating in isobaric mode, the increase in electron emission current (beam current), observed with increasing gas pressure, depends significantly on the type of gas used, as well as on the discharge current. The smallest increase in the emission current is observed when helium is used, and the largest increase is observed when argon is used. At gas pressure below some threshold pressure, which is dependent on the gas type (e.g. for nitrogen and oxygen below 7 Pa), increasing the discharge current leads to an increase in the electron emission efficiency, but at pressures higher than the threshold pressure, the emission efficiency decreases as the discharge current increases. Rise rate of emission current at the front of pulse increases with increasing gas pressure, and this increase in the rise rate of the emission current is more significant for the forevacuum e-beam source based on the constricted arc. The length of the accelerating gap (10–35 mm) has a significant influence on the rise rate of the emission current in the source based on the constricted arc discharge, while in the source based on the cathodic arc this influence is weaker. The observed dependences are related to ionization processes in the accelerating gap of the source and in the electron beam propagation region.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 4 supplement","pages":"S501 - S508"},"PeriodicalIF":0.48,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Highly Charged Metal Ions in Plasma of High-Current Short-Pulse Vacuum Arc
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2025-03-18 DOI: 10.1134/S1062873824710560
A. G. Nikolaev, V. D. Gridilev, G. Yu. Yushkov
{"title":"Highly Charged Metal Ions in Plasma of High-Current Short-Pulse Vacuum Arc","authors":"A. G. Nikolaev,&nbsp;V. D. Gridilev,&nbsp;G. Yu. Yushkov","doi":"10.1134/S1062873824710560","DOIUrl":"10.1134/S1062873824710560","url":null,"abstract":"<p>Highly charged beams of metal ions find many applications both in fundamental research in nuclear and atomic physics and in solving applied problems such as surface modification with ions. Now, the most effective and easy-to-implement method for producing metal ions of high charge states is the use of a high-current vacuum arc discharge of short duration. This paper presents experimental results on the generation of multiply charged metal ions based on vacuum arc plasma with a level current amplitude of about 3 kA and a level pulse duration of about 0.9 µs (full width at half maximum). Several cathode materials were investigated, such as silver, tin, lanthanum, gadolinium, and lead with atomic masses from 107.9 Da for silver to 207.2 Da for led. Also, these materials have a wide range of physical properties, such as atomic mass, melting point, heat capacity and thermal conductivity, etc. It was shown that with the specified parameters of the vacuum arc pulse, the maximum charge states for all studied materials are 11+, while the average charge is different and ranges from 7.8+ for tin to 9.6+ lanthanum. The degree of increase in the charge states of various materials is discussed.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 4 supplement","pages":"S530 - S537"},"PeriodicalIF":0.48,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Estimation of Radiation Efficiency of Cylindrical Porous Reactor for Combustion of Lean Premixed Methane–Air Mixture
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2025-03-18 DOI: 10.1134/S1062873824710493
E. V. Bazilevich, M. V. Muradova, A. V. Kulik, S. N. Mokrin, S. S. Minaev
{"title":"Estimation of Radiation Efficiency of Cylindrical Porous Reactor for Combustion of Lean Premixed Methane–Air Mixture","authors":"E. V. Bazilevich,&nbsp;M. V. Muradova,&nbsp;A. V. Kulik,&nbsp;S. N. Mokrin,&nbsp;S. S. Minaev","doi":"10.1134/S1062873824710493","DOIUrl":"10.1134/S1062873824710493","url":null,"abstract":"<p>The aim of this study was to estimate the radiation efficiency inside a cylindrical porous reactor consisting of two coaxially mounted quartz tubes. The porous medium was made of two different fractions of zirconium dioxide balls, which helped to stabilize the combustion wave for a wide range of combustible mixture flow rates, from 12.4 to 74.4 L/min. All experiments were performed using a premixed lean methane–air mixture. To estimate the radiative heat flux inside the porous reactor, the flow calorimetry method was utilized. The study found that the heat flux absorbed by water does not vary with the volume flow rate of the water. Furthermore, the experiment revealed that lower combustible mixture flow rates result in maximum radiative efficiency. This configuration of the porous reactor has the potential to be used as a heater for non-contact heating of materials through heat flow.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 4 supplement","pages":"S477 - S481"},"PeriodicalIF":0.48,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Narrow-Band Laser on the Active Medium of LiCaAlF6:Ce3+ Crystal
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2025-03-18 DOI: 10.1134/S1062873824710481
D. A. Makarova, A. S. Nizamutdinov, A. A. Shavelev, T. M. Minnebaev
{"title":"Narrow-Band Laser on the Active Medium of LiCaAlF6:Ce3+ Crystal","authors":"D. A. Makarova,&nbsp;A. S. Nizamutdinov,&nbsp;A. A. Shavelev,&nbsp;T. M. Minnebaev","doi":"10.1134/S1062873824710481","DOIUrl":"10.1134/S1062873824710481","url":null,"abstract":"<p>We described the design of a narrow-band laser based on the active medium of a LiCaAlF<sub>6</sub>:Ce<sup>3+</sup> crystal, generating in the ultraviolet range in the region of 281–316 nm. Narrowing of laser emission spectrum was achieved by integrating a Fabry–Pérot etalon into the dispersive cavity organized by to fused silica prisms. In this case, the laser emission bandwidth was 0.077 nm, the slope efficiency of laser output was 0.6%.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 4 supplement","pages":"S651 - S653"},"PeriodicalIF":0.48,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Nonlocal Condition for Electron Runaway in a Gas Diode with a Needle Cathode
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2025-03-18 DOI: 10.1134/S1062873824710602
M. A. Belyaev, M. A. Gashkov, M. I. Yalandin, N. M. Zubarev, O. V. Zubareva
{"title":"Nonlocal Condition for Electron Runaway in a Gas Diode with a Needle Cathode","authors":"M. A. Belyaev,&nbsp;M. A. Gashkov,&nbsp;M. I. Yalandin,&nbsp;N. M. Zubarev,&nbsp;O. V. Zubareva","doi":"10.1134/S1062873824710602","DOIUrl":"10.1134/S1062873824710602","url":null,"abstract":"<p>The conditions of electron runaway in an air gap with an inhomogeneous electric field caused by using a needle cathode are analyzed. Significant differences in the behavior of electrons have been revealed for different degrees of inhomogeneity of the field distribution provided by varying the radius of the needle tip. In a weakly inhomogeneous field (the radius of the tip exceeds a certain threshold), electrons are continuously accelerated throughout the gap. In a strongly inhomogeneous field (the tip radius is relatively small), electrons can reach maximum energy inside the gap and then begin to slow down in the near-anode region. The difference in the dynamics of free electrons leads to the need to use different, local or non-local, conditions for their runaway.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 4 supplement","pages":"S482 - S488"},"PeriodicalIF":0.48,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
The Influence of Sample Annealing on the Temperature Sensitivity of YF3:Tb3+, Eu3+ Temperature Sensors
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2025-03-18 DOI: 10.1134/S1062873824710365
E. I. Oleynikova, S. L. Korableva, O. A. Morozov, M. S. Pudovkin
{"title":"The Influence of Sample Annealing on the Temperature Sensitivity of YF3:Tb3+, Eu3+ Temperature Sensors","authors":"E. I. Oleynikova,&nbsp;S. L. Korableva,&nbsp;O. A. Morozov,&nbsp;M. S. Pudovkin","doi":"10.1134/S1062873824710365","DOIUrl":"10.1134/S1062873824710365","url":null,"abstract":"<p>The effect of two different post-treatment processing (annealing in air for 4 h at 400°C or annealing in NH<sub>4</sub>(HF<sub>2</sub>) for 4 h at 400°C) on the spectral characteristics of the samples was investigated. The YF<sub>3</sub>:Tb<sup>3+</sup> (1.0 mol %), Eu<sup>3+</sup> (0.5, 1.0, 2.0, and 4.0 mol %) samples were prepared using hydrothermal synthesis. The luminescence spectra of the samples in the temperature range of 80–320 K were detected in order to obtain the luminescence intensity ratio (LIR), which is a temperature-dependent parameter. The LIR function exhibited a monotonic behavior, which is advantageous for the use in luminescent thermometry. The sample with the highest temperature sensitivity was YF<sub>3</sub>:Tb<sup>3+</sup> (1.0 mol %), Eu<sup>3+</sup> (1.0 mol %). The temperature sensitivity for this sample was found to be equal to <i>S</i><sub>r</sub> = 0.44% K<sup>–1</sup> (80–150 K).</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 4 supplement","pages":"S580 - S586"},"PeriodicalIF":0.48,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638170","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Simulation of the Output Stage of Picosecond Multi-Gigawatt Electron Accelerator
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2025-03-18 DOI: 10.1134/S1062873824710572
V. E. Patrakov, S. N. Rukin, S. A. Shunailov, M. I. Yalandin
{"title":"Simulation of the Output Stage of Picosecond Multi-Gigawatt Electron Accelerator","authors":"V. E. Patrakov,&nbsp;S. N. Rukin,&nbsp;S. A. Shunailov,&nbsp;M. I. Yalandin","doi":"10.1134/S1062873824710572","DOIUrl":"10.1134/S1062873824710572","url":null,"abstract":"<p>We presented the results of numerical simulation of the output path of a picosecond electron accelerator based on a solid-state generator with a peak power of 100 GW and an output pulse duration of 100 ps and an IMA3-150E vacuum diode. The simulation is conducted in time domain and is based on vector potential form of Maxwell’s equations coupled to a nonlinear lumped element governed by Child-Langmuir law to describe the interaction of the travelling wave with the electron beam current. Particular attention is paid to pulse distortions on path discontinuities, as well as distortions associated with energy losses in the line conductors and in the transformer oil filling the line. A time-domain model of dielectric losses in transformer oil is presented based on experimental data. The simulation results include the calculation of optimal parameters of the conical transition between the generator and the diode, simulated time-domain reflectometry analysis of the vacuum diode, evaluation of the influence of path discontinuities on pulse distortion, and an estimation of the parameters of the electron beam, which amounted to: maximum energy of 2.6 MeV, current of 21 kA, current pulse duration of 115 ps.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 4 supplement","pages":"S538 - S545"},"PeriodicalIF":0.48,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638324","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Features of Degenerate Defect Modes in One-Dimensional Photonic Crystals with Two Defects
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2025-02-27 DOI: 10.1134/S1062873824709796
A. O. Kamenev, N. A. Vanyushkin, I. M. Efimov, S. S. Golik, A. H. Gevorgyan
{"title":"Features of Degenerate Defect Modes in One-Dimensional Photonic Crystals with Two Defects","authors":"A. O. Kamenev,&nbsp;N. A. Vanyushkin,&nbsp;I. M. Efimov,&nbsp;S. S. Golik,&nbsp;A. H. Gevorgyan","doi":"10.1134/S1062873824709796","DOIUrl":"10.1134/S1062873824709796","url":null,"abstract":"<p>The different cases of degenerate defect modes in one-dimensional photonic crystals with two defect layers are studied. Degenerate defect modes occur when two or more defect modes merge at a given wavelength in the photonic crystal reflection spectrum. Such defect modes have a variety of potential practical applications, including the increase of sensitivity in optical sensors. The appearance of each type of degenerate defect modes is determined by the structural features and parameters of the photonic crystal. For this reason, we have derived analytical equations containing the photonic crystal parameters describing each type of defect modes merging. Analytical expressions for the zero imaginary phase for any type of defect mode merging have been also obtained. These general relationships can be used to simplify the modeling of one-dimensional photonic crystals with two defect layers and for further analysis of degenerate defect modes.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 3 supplement","pages":"S340 - S347"},"PeriodicalIF":0.48,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143496833","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Quasi-Two-Dimensional Gold Films for Plasmonic and Optoelectronic Applications
IF 0.48
Bulletin of the Russian Academy of Sciences: Physics Pub Date : 2025-02-27 DOI: 10.1134/S1062873824710018
D. I. Yakubovsky, M. S. Mironov, A. S. Slavich, D. V. Grudinin, I. S. Kazantsev, G. A. Ermolaev, A. V. Arsenin, V. S. Volkov
{"title":"Quasi-Two-Dimensional Gold Films for Plasmonic and Optoelectronic Applications","authors":"D. I. Yakubovsky,&nbsp;M. S. Mironov,&nbsp;A. S. Slavich,&nbsp;D. V. Grudinin,&nbsp;I. S. Kazantsev,&nbsp;G. A. Ermolaev,&nbsp;A. V. Arsenin,&nbsp;V. S. Volkov","doi":"10.1134/S1062873824710018","DOIUrl":"10.1134/S1062873824710018","url":null,"abstract":"<p>Ultrathin metal films are an important element for transparent optoelectronics including displays, photovoltaics and sensors, where the use of flexible and durable electrodes is needed. Nevertheless, fabrication of ultrathin, continuous and smooth metal films is quite challenging and restricted by a variety of factors, including deposition techniques and substrate. Much effort has been expended in creating ultrathin gold and silver films as transparent conductor, but the methods developed have often been limited to the choice of substrate and its surface modification, thus transferring the already resulted ultrathin film to the target surface looks promising. Here, we introduce a facile technique for fabrication and transfer of ultrathin (&lt;10 nm) gold films onto target substrate presenting their structural morphology and electrical properties analysis, which showed high quality and low sheet resistance of the obtained gold films.</p>","PeriodicalId":504,"journal":{"name":"Bulletin of the Russian Academy of Sciences: Physics","volume":"88 3 supplement","pages":"S457 - S460"},"PeriodicalIF":0.48,"publicationDate":"2025-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143496667","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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