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Simulation of the Outflow of Supersonic Jets into a Rarefied Medium in Pulse Modes 脉冲模式下超音速射流进入稀薄介质的模拟
IF 0.4 4区 工程技术
Instruments and Experimental Techniques Pub Date : 2025-02-03 DOI: 10.1134/S0020441224701550
A. E. Zarvin, V. V. Kalyada, A. S. Yaskin, K. A. Dubrovin, E. D. Dering, V. E. Khudozhitkov
{"title":"Simulation of the Outflow of Supersonic Jets into a Rarefied Medium in Pulse Modes","authors":"A. E. Zarvin,&nbsp;V. V. Kalyada,&nbsp;A. S. Yaskin,&nbsp;K. A. Dubrovin,&nbsp;E. D. Dering,&nbsp;V. E. Khudozhitkov","doi":"10.1134/S0020441224701550","DOIUrl":"10.1134/S0020441224701550","url":null,"abstract":"<p>The use of electromagnetic valves for generating pulsed flow modes of a high-density supersonic jet in the second and submillisecond ranges is analyzed. It has been shown that “slow” second-range valves do not allow achieving a quasi-stationary mode with a high gas flow rate compared to a stationary outflow; submillisecond-range “fast” valves generate gas pulses with parameters necessary to simulate high-flow conditions at background gas pressures that do not overload the high-vacuum pumping system. It is found that the submillisecond valve provides the ability to simulate instantaneous flow rates of up to several tens of grams of a product per second in a pulse at pressures in the prechamber of up to 2 MPa and a pressure in the surrounding space of 1–3 Pa. A set of sonic and supersonic nozzles has been implemented with an electromagnetic valve device and power-supply and control systems that provide the gas outflow from the nozzle prechamber during a controlled period of time from 0.3 to 1.5 ms with a given duty cycle varying from several tens to thousands. The generated gas pulses have a trapezoidal shape with a quasi-stationary core.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":"67 5","pages":"1051 - 1058"},"PeriodicalIF":0.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108301","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Development of an MDSPlus-based Data Acquisition and Management System for Tokamak Devices 基于mdspls的托卡马克设备数据采集与管理系统的开发
IF 0.4 4区 工程技术
Instruments and Experimental Techniques Pub Date : 2025-02-03 DOI: 10.1134/S0020441224701422
Shuangbao Shu, Ziqiang Yang, Shurui Zhang, Jiyao Wang, Yong Wang
{"title":"Development of an MDSPlus-based Data Acquisition and Management System for Tokamak Devices","authors":"Shuangbao Shu,&nbsp;Ziqiang Yang,&nbsp;Shurui Zhang,&nbsp;Jiyao Wang,&nbsp;Yong Wang","doi":"10.1134/S0020441224701422","DOIUrl":"10.1134/S0020441224701422","url":null,"abstract":"<p>In Tokamak experiments, the MDSPlus database is commonly used for data management. It collects and stores data from each subsystem. However, the complexity and high coupling of the system make it vulnerable to failure. If one module malfunctions, it can cause the entire system to collapse, hindering future maintenance and expansion. To address this issue, this paper proposes a data acquisition and management system based on the PCI-1706 multi-channel synchronous data acquisition cards and the MDSPlus database, along with a data Scope program. The data acquisition system employs a multi-process design to achieve synchronization among multiple channels by using an external clock and trigger signal. Meanwhile, the data management system utilizes MDSPlus, and a client Scope program is developed to enable remote data access and analysis. The reflection memory card is employed to establish a network for data interaction between the server and the acquisition machine, enhancing storage speed. Experimental tests have confirmed the multi-card and multi-channel synchronous acquisition functions of the data acquisition system, as well as the remote data access capability of the Scope program. This system exhibits advantages such as low cost, simple structure, stable operation, and easy maintenance. It proves to be effective in Tokamak device experiments and can also serve as a reference for other data management systems.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":"67 5","pages":"892 - 901"},"PeriodicalIF":0.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Measuring Magnetization Curves of Ferrofluids: Comparison of the Differential Sweep Method and a Vibrating-Sample Magnetometer 铁磁流体磁化曲线的测量：差示扫描法与振动样品磁强计的比较
IF 0.4 4区 工程技术
Instruments and Experimental Techniques Pub Date : 2025-02-03 DOI: 10.1134/S0020441224701574
A. V. Lebedev
{"title":"Measuring Magnetization Curves of Ferrofluids: Comparison of the Differential Sweep Method and a Vibrating-Sample Magnetometer","authors":"A. V. Lebedev","doi":"10.1134/S0020441224701574","DOIUrl":"10.1134/S0020441224701574","url":null,"abstract":"<p>A setup design is proposed for measuring magnetization curves by the differential sweep method. On the described setup, a number of magnetization curves were measured for both classical magnetic fluids and samples obtained by their solidification. The measurement results are compared with the results obtained using a vibrating-sample magnetometer. It is shown that the vibrating-sample magnetometer gives significantly lower values compared to the differential method when measuring the magnetization of a magnetic fluid. When measuring the magnetization of a cured magnetic-fluid sample, a complete coincidence of the results obtained by both measurement methods is observed. The discovered phenomenon is explained by the aggregation of particles in the magnetic fluid under the influence of a magnetic field. Estimations of the relative delay in the movement of aggregates are consistent with the observed divergence in the magnetization magnitude.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":"67 5","pages":"989 - 994"},"PeriodicalIF":0.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108300","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Investigation of the Spectral Composition of X-Ray Radiation from Femtosecond Laser Plasma by Thermoluminescent Detectors 热释光探测器对飞秒激光等离子体x射线辐射光谱组成的研究
IF 0.4 4区 工程技术
Instruments and Experimental Techniques Pub Date : 2025-02-03 DOI: 10.1134/S002044122470163X
G. H. Salakhutdinov, K. A. Ivanov, I. G. Grigoryeva, V. V. Kushin, A. A. Rupasov, I. N. Tsymbalov, A. B. Savelyev-Trofimov, I. A. Busygina, P. Yu. Naumov
{"title":"Investigation of the Spectral Composition of X-Ray Radiation from Femtosecond Laser Plasma by Thermoluminescent Detectors","authors":"G. H. Salakhutdinov,&nbsp;K. A. Ivanov,&nbsp;I. G. Grigoryeva,&nbsp;V. V. Kushin,&nbsp;A. A. Rupasov,&nbsp;I. N. Tsymbalov,&nbsp;A. B. Savelyev-Trofimov,&nbsp;I. A. Busygina,&nbsp;P. Yu. Naumov","doi":"10.1134/S002044122470163X","DOIUrl":"10.1134/S002044122470163X","url":null,"abstract":"<p>A technique based on thermoluminescent LiF(Mg,Ti) lithium fluoride detectors has been developed to study the spectral composition of  X-ray radiation of femtosecond laser plasma in a wide range of photon energies from 1 keV to almost 1 MeV. This technique has been experimentally tested together with matrix-type semiconductor detectors. The plasma parameters have been measured under the action of a femtosecond pulse with a peak intensity of ~10<sup>18</sup> W/cm<sup>2</sup> on a metal (copper) target, and good agreement is demonstrated between data from different detector types in terms of determining both the spectrum shape and the coefficient of the laser-pulse energy conversion into an X-ray flux. The temperature of hot electrons has been estimated, and its value exceeds 100 keV. The X-ray flux of copper <i>K</i>-lines, which exceeds 10<sup>9</sup> per shot, has been determined. The advantages and drawbacks of techniques for measuring spectra in problems of laser-plasma interaction are considered.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":"67 5","pages":"971 - 976"},"PeriodicalIF":0.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108297","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Application of a Laser-Plasma Accelerator to Study Single Event Effects in a Microelectronic Device 激光等离子体加速器在微电子器件单事件效应研究中的应用
IF 0.4 4区 工程技术
Instruments and Experimental Techniques Pub Date : 2025-02-03 DOI: 10.1134/S0020441224701641
K. V. Safronov, V. A. Flegentov, S. A. Gorokhov, N. N. Shamaeva, A. S. Tishchenko, D. O. Zamuraev, A. L. Shamraev, S. F. Kovaleva, N. A. Fedorov, S. M. Dubrovskikh, A. S. Pilipenko, A. S. Kustov, E. A. Shibakov, A. V. Potapov
{"title":"Application of a Laser-Plasma Accelerator to Study Single Event Effects in a Microelectronic Device","authors":"K. V. Safronov,&nbsp;V. A. Flegentov,&nbsp;S. A. Gorokhov,&nbsp;N. N. Shamaeva,&nbsp;A. S. Tishchenko,&nbsp;D. O. Zamuraev,&nbsp;A. L. Shamraev,&nbsp;S. F. Kovaleva,&nbsp;N. A. Fedorov,&nbsp;S. M. Dubrovskikh,&nbsp;A. S. Pilipenko,&nbsp;A. S. Kustov,&nbsp;E. A. Shibakov,&nbsp;A. V. Potapov","doi":"10.1134/S0020441224701641","DOIUrl":"10.1134/S0020441224701641","url":null,"abstract":"<p>Bit flip errors were detected in microcontroller memory cells after irradiation by laser accelerated proton beams. The protons with energies of up to 6 MeV originated from the back surface of 6-μm-thick aluminum foils under the action of laser pulses from 200 TW femtosecond facility. It was established that the failures were caused by single event effects and cross section of the effects was estimated. The experiment demonstrates for the first time the possibility of using laser-plasma accelerators to study single event effects from low-energy protons.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":"67 5","pages":"952 - 957"},"PeriodicalIF":0.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108299","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Method of Optimizing the Distribution of Capacitor Capacities in a Voltage Multiplier Based on the Criterion of Mass-Power Characteristics 基于质量-功率特性准则的电压倍增器电容容量优化分配方法
IF 0.4 4区 工程技术
Instruments and Experimental Techniques Pub Date : 2025-02-03 DOI: 10.1134/S0020441224701549
Ya. E. Zharkov, A. S. Kirillov, S. I. Moshkunov, A. B. Prokofiev, V. Y. Khomich
{"title":"Method of Optimizing the Distribution of Capacitor Capacities in a Voltage Multiplier Based on the Criterion of Mass-Power Characteristics","authors":"Ya. E. Zharkov,&nbsp;A. S. Kirillov,&nbsp;S. I. Moshkunov,&nbsp;A. B. Prokofiev,&nbsp;V. Y. Khomich","doi":"10.1134/S0020441224701549","DOIUrl":"10.1134/S0020441224701549","url":null,"abstract":"<p>This article describes a method for optimizing the distribution of capacitances of a voltage multiplier. This action is necessary to reduce the weight of the device without reducing the output power at the load. The simulation was carried out for the case of an input voltage of 950 V, an output voltage of 10 kV, a frequency of 750 kHz, and a capacitance range from 1 to 25 nF. A comparison was made for constant and variable capacity. It is shown that using the dependence of capacitance on capacitor number allows for reducing mass of the device by 7% compared with a constant distribution. The main elements of a voltage multiplier are diodes and capacitors. A diode and a capacitor connected in parallel form a stage that increases the voltage amplitude. A pair of series connected steps form a cascade. In addition to increasing the output voltage, the first stage cuts off the negative components of a signal, and the second one cuts off the positive one.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":"67 5","pages":"919 - 928"},"PeriodicalIF":0.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108173","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Prototype Readout Electronics for Capacitive Detectors 电容式检测器的原型读出电子器件
IF 0.4 4区 工程技术
Instruments and Experimental Techniques Pub Date : 2025-02-03 DOI: 10.1134/S002044122470146X
E. V. Atkin, D. D. Normanov, S. I. Yamaliev, A. R. Serazetdinov, A. A. Solin, E. A. Usenko
{"title":"Prototype Readout Electronics for Capacitive Detectors","authors":"E. V. Atkin,&nbsp;D. D. Normanov,&nbsp;S. I. Yamaliev,&nbsp;A. R. Serazetdinov,&nbsp;A. A. Solin,&nbsp;E. A. Usenko","doi":"10.1134/S002044122470146X","DOIUrl":"10.1134/S002044122470146X","url":null,"abstract":"<p>This article presents the description of a prototype readout electronics for capacitive detectors based on an application-specific integrated circuit (ASIC) designed specifically for the readout and pre-processing of signals from the flat resistive chambers of the SPD (spectrometer with pixel detectors) experiment at the NICA collider under construction at JINR (Joint Institute for Nuclear Research) in Dubna. The eight-channel ASIC is optimized to work with detectors featuring a characteristic impedance of the readout electrodes in the range of 35–110 Ω, with an equivalent input noise charge of no more than 2500 electrons. The ASIC includes adjustments for the threshold by the input charge in the range of 10–450 fC, hysteresis of the threshold characteristic in the range of 0–12%, and signal extension time in the range of 0.5–100 ns. The circuit was optimized to reduce jitter on the front edge (less than 10 ps) and power consumption (less than 25 mW per channel).</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":"67 5","pages":"935 - 941"},"PeriodicalIF":0.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108127","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Energy Resolution of a Spectrometer with an Oriented Crystal Converter 定向晶体转换器光谱仪的能量分辨率
IF 0.4 4区 工程技术
Instruments and Experimental Techniques Pub Date : 2025-02-03 DOI: 10.1134/S0020441224701483
V. A. Baskov
{"title":"Energy Resolution of a Spectrometer with an Oriented Crystal Converter","authors":"V. A. Baskov","doi":"10.1134/S0020441224701483","DOIUrl":"10.1134/S0020441224701483","url":null,"abstract":"<p>A single-crystal converter oriented along the axis is placed in front of an electromagnetic spectrometer to change the response of the spectrometer that measures electrons with energies of several tens of GeV. The relative energy resolution of the spectrometer is improved by 15−80% depending on the orientation, thickness, and type of the crystal converter and the spectrometer thickness at electron energies of 26 and 28 GeV.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":"67 5","pages":"870 - 880"},"PeriodicalIF":0.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Use of the Nanogate‑38 Camera for Beam Diagnostics at the VEPP‑2000 Collider 在VEPP‑2000对撞机上使用Nanogate‑38相机进行光束诊断
IF 0.4 4区 工程技术
Instruments and Experimental Techniques Pub Date : 2025-02-03 DOI: 10.1134/S0020441224701653
M. V. Timoshenko, V. E. Boyarkina, V. L. Dorokhov, M. I. Krutik, O. I. Meshkov, I. A. Terent’ev
{"title":"Use of the Nanogate‑38 Camera for Beam Diagnostics at the VEPP‑2000 Collider","authors":"M. V. Timoshenko,&nbsp;V. E. Boyarkina,&nbsp;V. L. Dorokhov,&nbsp;M. I. Krutik,&nbsp;O. I. Meshkov,&nbsp;I. A. Terent’ev","doi":"10.1134/S0020441224701653","DOIUrl":"10.1134/S0020441224701653","url":null,"abstract":"<p>The Nanogate‑38 gated camera was used to measure the transverse beam dimensions in the BEP booster of the VEPP‑2000 electron−positron collider. The camera is used to measure the vertical beam size by a double-slit interferometer and to visualize a transverse beam profile in single-turn mode with the projection optics. The purpose of the experiments is to assess the applicability of the camera to measurements of the transverse beam dimensions and beam emittance in accelerator experiments at the SKIF synchrotron-radiation source.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":"67 5","pages":"858 - 864"},"PeriodicalIF":0.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
Four-Photon Josephson Traveling Wave Parametric Amplifier 四光子约瑟夫逊行波参量放大器
IF 0.4 4区 工程技术
Instruments and Experimental Techniques Pub Date : 2025-02-03 DOI: 10.1134/S0020441224701586
A. A. Lomonosov, R. V. Kubrakov, L. V. Filippenko, R. K. Kozulin, V. A. Krupenin, V. K. Kornev, M. A. Tarasov
{"title":"Four-Photon Josephson Traveling Wave Parametric Amplifier","authors":"A. A. Lomonosov,&nbsp;R. V. Kubrakov,&nbsp;L. V. Filippenko,&nbsp;R. K. Kozulin,&nbsp;V. A. Krupenin,&nbsp;V. K. Kornev,&nbsp;M. A. Tarasov","doi":"10.1134/S0020441224701586","DOIUrl":"10.1134/S0020441224701586","url":null,"abstract":"<p>Josephson traveling wave parametric amplifiers can have high gain and wide frequency range, high sensitivity, and low noise, which makes them promising for quantum computing, array receiver readout systems, spectroscopy, single-photon detectors, etc. In this paper, the authors investigate samples of traveling wave parametric amplifiers based on a three-layer Nb/AlO<sub><i>x</i></sub>/Nb superconductor–insulator–superconductor (SIS) structure with a SNAIL (Superconducting Nonlinear Asymmetric Inductive Elements) series array. Each SNAIL cell consists of the kinetic inductance of four SIS junctions and the nonlinear inductance of a smaller SIS junction. The cells are alternately connected in antiphase with respect to the magnetic flux, which ensures a change in the sign of the Kerr nonlinearity and a reduction in the phase mismatch for the pump frequency, signal frequency, and idler frequency. The transmission spectra of the samples were measured at temperatures of 4.2 and 2.8 K in the frequency range of 0.1–6 GHz.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":"67 5","pages":"911 - 918"},"PeriodicalIF":0.4,"publicationDate":"2025-02-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S0020441224701586.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143108243","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
引用次数: 0
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