Pub Date : 2024-07-08DOI: 10.1134/s0020441224700581
A. K. Fomin, A. P. Serebrov
Abstract
When ultracold neutrons interact with moving surfaces, their energy can change (so-called turbine effect). In this case, both an increase and a decrease in the neutron energy are possible. In previous experiments with the capture of ultracold neutrons in a gravitational trap by rotating it, it was made to have the shape of a body of revolution, which was done specifically to avoid the turbine effect. In this paper, the authors consider an experiment with a rotating gravitational trap that does not have the shape of a body of revolution. The Monte Carlo method was used to simulate the turbine effect at different stages of the experiment. The transformation of the neutron spectrum over time is calculated as a function of the trap rotation speed. A possible systematic error in the measurement of the neutron lifetime due to the influence of the turbine effect is considered. Experimental parameters are obtained for which it is absent.
{"title":"Turbine Effect in an Experiment with Storage of Ultracold Neutrons","authors":"A. K. Fomin, A. P. Serebrov","doi":"10.1134/s0020441224700581","DOIUrl":"https://doi.org/10.1134/s0020441224700581","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>When ultracold neutrons interact with moving surfaces, their energy can change (so-called turbine effect). In this case, both an increase and a decrease in the neutron energy are possible. In previous experiments with the capture of ultracold neutrons in a gravitational trap by rotating it, it was made to have the shape of a body of revolution, which was done specifically to avoid the turbine effect. In this paper, the authors consider an experiment with a rotating gravitational trap that does not have the shape of a body of revolution. The Monte Carlo method was used to simulate the turbine effect at different stages of the experiment. The transformation of the neutron spectrum over time is calculated as a function of the trap rotation speed. A possible systematic error in the measurement of the neutron lifetime due to the influence of the turbine effect is considered. Experimental parameters are obtained for which it is absent.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141567163","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}
Pub Date : 2024-06-28DOI: 10.1134/s0020441224700283
V. P. Tarasikov
Abstract—
A high-temperature (up to 1600°C) installation for measuring the coefficient of linear expansion (CLE) using a relative method is described. The measuring unit is installed in a protective glove box, which allowed measurements to be performed on samples irradiated in a reactor. Changes in the length of the sample during heating were recorded with a clock-type indicator head with an accuracy of 1 μm with the measurement range of 0–10 mm. The installation was used to determine the values of swelling of irradiated samples during high-temperature annealing and to obtain the values of the CLE of promising reactor materials. The average relative measurement error is 8–11%.
{"title":"A High-Temperature Installation for Measuring the Coefficient of Linear Expansion","authors":"V. P. Tarasikov","doi":"10.1134/s0020441224700283","DOIUrl":"https://doi.org/10.1134/s0020441224700283","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract—</h3><p>A high-temperature (up to 1600°C) installation for measuring the coefficient of linear expansion (CLE) using a relative method is described. The measuring unit is installed in a protective glove box, which allowed measurements to be performed on samples irradiated in a reactor. Changes in the length of the sample during heating were recorded with a clock-type indicator head with an accuracy of 1 μm with the measurement range of 0–10 mm. The installation was used to determine the values of swelling of irradiated samples during high-temperature annealing and to obtain the values of the CLE of promising reactor materials. The average relative measurement error is 8–11%.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141525011","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}
Pub Date : 2024-06-28DOI: 10.1134/s0020441224700052
D. A. Bobylev, M. D. Siomash, V. V. Khankin, V. I. Shvedunov
Abstract
The article presents the results of the development of an energy sensor designed to control the energy of an electron beam released into the atmosphere from accelerators for applied purposes. The principle of operation of the device is based on the use of Vavilov–Cherenkov radiation, which occurs when an electron beam passes through a gas.
{"title":"Electron Beam Energy Sensor Based on the Vavilov–Cherenkov Effect","authors":"D. A. Bobylev, M. D. Siomash, V. V. Khankin, V. I. Shvedunov","doi":"10.1134/s0020441224700052","DOIUrl":"https://doi.org/10.1134/s0020441224700052","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The article presents the results of the development of an energy sensor designed to control the energy of an electron beam released into the atmosphere from accelerators for applied purposes. The principle of operation of the device is based on the use of Vavilov–Cherenkov radiation, which occurs when an electron beam passes through a gas.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141525021","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}
Pub Date : 2024-06-28DOI: 10.1134/s0020441224700131
A. L. Despotuli, V. V. Kazmiruk, A. A. Despotuli, A. V. Andreeva
Abstract
The purpose of the article is to show the advantages of a new design of a high-voltage rectangular pulse generator. Known analogues combine modules: signal generator; high-voltage key of N identical transistors (Qk, k = 1….N) connected in series; gate driver of leading Qk; high-voltage power source, its electromotive force, emf (E), feeds all Qk and load (R) of the key. In analogs, divider resistors (rk) and snubbers balance equality of voltages Uk on all Qk. Under nonideal balance conditions E ≈ 0.7NUmax, where Umax is the maximum operating voltage of Qk. The new solution differs in that the high-voltage power source sets not one but N emf Ek (Ei/Ej = const (i, j); i ≠ j; i, j = 1, 2, …, N) and each Ek feeds its Qk through the load Rk. Experiments and simulations have revealed advantages of the new design: (1) the simplicity of the circuit and key tuning, (2) the fast transition ON→OFF for all Qk (as Rk is small, Rk( ll )rk), (3) the high pulse repetition rate, and (4) the greatly improved balancing of Uk voltages allows the Ek emf to be set so that ΣUk ≈ ΣUk, max at Ui, max ≠ Uk, max. The generator with the key based on two different MOSFETs (IXTL2N450 and IXTT1N450HV, Umax = 4500 V) and with a source where the E2 = 2E1 were used to excite vacuum ion emission from liquid Ga-based alloys.
摘要 本文旨在说明高压矩形脉冲发生器新设计的优点。已知的模拟装置由以下模块组成:信号发生器;由 N 个相同晶体管 (Qk, k = 1....N) 串联而成的高压键;前导 Qk 的栅极驱动器;高压电源,其电动势 emf (E) 供给所有 Qk 和键的负载 (R)。在模拟电路中,分压器电阻器 (rk) 和缓冲器可平衡所有 Qk 上的电压。在非理想平衡条件下,E ≈ 0.7NUmax,其中 Umax 是 Qk 的最大工作电压。新方案的不同之处在于,高压电源设置的不是一个,而是 N 个 emf Ek(Ei/Ej = const (i, j); i ≠ j; i, j = 1, 2, ..., N),每个 Ek 都通过负载 Rk 为其 Qk 供电。实验和模拟揭示了新设计的优势:(1) 电路和按键调整简单;(2) 对所有 Qk 都能快速实现 ON→OFF 转换(由于 Rk 很小,Rk ( ll )rk);(3) 脉冲重复率高;(4) 大大提高了 Uk 电压的平衡性,使 Ek emf 可以在 Ui, max ≠ Uk, max 时设置为 ΣUk ≈ ΣUk, max。基于两个不同 MOSFET(IXTL2N450 和 IXTT1N450HV,Umax = 4500 V)的键发生器和 E2 = 2E1 的源被用于激发液态镓基合金的真空离子发射。
{"title":"A Generator of Rectangular Pulses Based on a Serial Connection of Mosfet with Umax = 4500 V","authors":"A. L. Despotuli, V. V. Kazmiruk, A. A. Despotuli, A. V. Andreeva","doi":"10.1134/s0020441224700131","DOIUrl":"https://doi.org/10.1134/s0020441224700131","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The purpose of the article is to show the advantages of a new design of a high-voltage rectangular pulse generator. Known analogues combine modules: signal generator; high-voltage key of <i>N</i> identical transistors (<i>Q</i><sub><i>k</i></sub>, <i>k</i> = 1….<i>N</i>) connected in series; gate driver of leading <i>Q</i><sub><i>k</i></sub>; high-voltage power source, its electromotive force, emf (<i>E</i>), feeds all <i>Q</i><sub><i>k</i></sub> and load (<i>R</i>) of the key. In analogs, divider resistors (<i>r</i><sub><i>k</i></sub>) and snubbers balance equality of voltages <i>U</i><sub><i>k</i></sub> on all <i>Q</i><sub><i>k</i></sub>. Under nonideal balance conditions <i>E</i> ≈ 0.7<i>NU</i><sub>max</sub>, where <i>U</i><sub>max</sub> is the maximum operating voltage of <i>Q</i><sub><i>k</i></sub>. The new solution differs in that the high-voltage power source sets not one but <i>N</i> emf <i>E</i><sub><i>k</i></sub> (<i>E</i><sub><i>i</i></sub>/<i>E</i><sub><i>j</i></sub> = const (<i>i</i>, <i>j</i>); <i>i</i> ≠ <i>j</i>; <i>i</i>, <i>j =</i> 1, 2, …, <i>N</i>) and each <i>E</i><sub><i>k</i></sub> feeds its <i>Q</i><sub><i>k</i></sub> through the load <i>R</i><sub><i>k</i></sub>. Experiments and simulations have revealed advantages of the new design: (1) the simplicity of the circuit and key tuning, (2) the fast transition ON→OFF for all <i>Q</i><sub><i>k</i></sub> (as <i>R</i><sub><i>k</i></sub> is small, <i>R</i><sub><i>k</i></sub> <span>( ll )</span> <i>r</i><sub><i>k</i></sub>), (3) the high pulse repetition rate, and (4) the greatly improved balancing of <i>U</i><sub><i>k</i></sub> voltages allows the <i>E</i><sub><i>k</i></sub> emf to be set so that Σ<i>U</i><sub><i>k</i></sub> ≈ Σ<i>U</i><sub><i>k</i>, max</sub> at <i>U</i><sub><i>i</i>, max</sub> ≠ <i>U</i><sub><i>k</i>, max</sub>. The generator with the key based on two different MOSFETs (IXTL2N450 and IXTT1N450HV, <i>U</i><sub>max</sub> = 4500 V) and with a source where the <i>E</i><sub>2</sub> = 2<i>E</i><sub>1</sub> were used to excite vacuum ion emission from liquid Ga-based alloys.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141525110","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}
Pub Date : 2024-06-28DOI: 10.1134/s002044122470009x
E. D. Vovchenko, K. I. Kozlovskii, R. P. Pleshakova, A. A. Rukhman, A. E. Shikanov
Abstract
The possibility of using synthetic diamond crystals as a sensitive element of resistive-type thermal sensors developed to control target heating in a neutron generator is discussed. Information about the design and manufacturing technology of a mock-up sample of the temperature sensor, as well as data from an experimental study of its dynamic characteristics, are given. On the example of a neutron generator developed based on a high-current accelerating diode, a scheme for thermal control of a neutron-forming target is proposed.
{"title":"On the Possibility of Using Synthetic Diamonds to Control the Temperature of Targets in Neutron Generators","authors":"E. D. Vovchenko, K. I. Kozlovskii, R. P. Pleshakova, A. A. Rukhman, A. E. Shikanov","doi":"10.1134/s002044122470009x","DOIUrl":"https://doi.org/10.1134/s002044122470009x","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The possibility of using synthetic diamond crystals as a sensitive element of resistive-type thermal sensors developed to control target heating in a neutron generator is discussed. Information about the design and manufacturing technology of a mock-up sample of the temperature sensor, as well as data from an experimental study of its dynamic characteristics, are given. On the example of a neutron generator developed based on a high-current accelerating diode, a scheme for thermal control of a neutron-forming target is proposed.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141508726","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}
Pub Date : 2024-06-28DOI: 10.1134/s0020441224700271
I. A. Suslov, I. B. Nemchenok, A. A. Klimenko, A. D. Bystryakov, I. I. Kamnev
Abstract
The first results from the development of previously unknown tellurium-loaded plastic scintillators based on polystyrene, poly(methyl methacrylate), and their copolymers for detectors for the search and study of neutrinoless double beta decay are reported herein. A complex compound of diphenyltellurium oxide with di-(2-ethylhexyl)phosphoric acid and diphenyltellurium di-2-ethylhexanoate were used as tellurium-containing additives. The conditions for obtaining samples have been described and their light yield and transparency has been characterized.
{"title":"Tellurium-Loaded Plastic Scintillators","authors":"I. A. Suslov, I. B. Nemchenok, A. A. Klimenko, A. D. Bystryakov, I. I. Kamnev","doi":"10.1134/s0020441224700271","DOIUrl":"https://doi.org/10.1134/s0020441224700271","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The first results from the development of previously unknown tellurium-loaded plastic scintillators based on polystyrene, poly(methyl methacrylate), and their copolymers for detectors for the search and study of neutrinoless double beta decay are reported herein. A complex compound of diphenyltellurium oxide with di-(2-ethylhexyl)phosphoric acid and diphenyltellurium di-2-ethylhexanoate were used as tellurium-containing additives. The conditions for obtaining samples have been described and their light yield and transparency has been characterized.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141532026","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}
Pub Date : 2024-06-28DOI: 10.1134/s0020441224700015
Avijit Das, Rajendra P. Giri, Mrinmay K. Mukhopadhyay
Abstract
An oxygen-free copper-based cell has been designed to perform X-ray scattering experiments from the solid-supported lipid membranes immersed in water. This cell can be used to investigate the structural changes in the membrane depending on the composition of the lipids, the effects of temperatures, and the changes in arrangements of the lipids in the membrane on the addition of the external molecules. The design of the cell has been optimized to get a good signal-to-noise ratio (SNR) for the measurements of X-ray reflectivity and grazing incidence diffraction by controlling the X-ray path within the liquid in the cell and easy operation for variable liquid temperature. This very low-cost temperature-controlled setup, developed in our laboratory, can perform in situ X-ray measurements at various temperature ranges—starting from around 4°C up to 70°C which is very relevant to study the phase transition temperature of the lipids constituting the cell membranes. The detailed mechanical design of the cell and electrical control mechanism of the temperature of the liquid inside the cell has been discussed here. One such X-ray reflectivity measurement is shown here to express the capability of the cell for the study of the solid-supported bilayer sample composed of dipalmitoyl phosphocholine lipid at two different temperatures, below its phase transition temperature.
摘要 设计了一种无氧铜基电池,用于对浸入水中的固体支撑脂质膜进行 X 射线散射实验。该样品池可用于研究膜的结构变化取决于脂质的组成、温度的影响以及外部分子加入时膜中脂质排列的变化。对样品池的设计进行了优化,通过控制样品池液体中的 X 射线路径,在测量 X 射线反射率和掠入射衍射时获得了良好的信噪比(SNR),并且易于操作以改变液体温度。我们实验室开发的这种温控装置成本非常低,可以在从 4°C 左右到 70°C 的各种温度范围内进行原位 X 射线测量,这与研究构成细胞膜的脂质的相变温度非常相关。这里讨论了细胞的详细机械设计和细胞内液体温度的电气控制机制。其中一个 X 射线反射率测量结果表明,该样品池能够在低于相变温度的两个不同温度下研究由二棕榈酰基磷酸胆碱脂质组成的固态支撑双分子层样品。
{"title":"Design of a Liquid Cell for Structural Investigations of Supported Lipid Membrane by Synchrotron X-Rays Over a Wide Temperature Range, from Lower to Higher than Ambient","authors":"Avijit Das, Rajendra P. Giri, Mrinmay K. Mukhopadhyay","doi":"10.1134/s0020441224700015","DOIUrl":"https://doi.org/10.1134/s0020441224700015","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>An oxygen-free copper-based cell has been designed to perform X-ray scattering experiments from the solid-supported lipid membranes immersed in water. This cell can be used to investigate the structural changes in the membrane depending on the composition of the lipids, the effects of temperatures, and the changes in arrangements of the lipids in the membrane on the addition of the external molecules. The design of the cell has been optimized to get a good signal-to-noise ratio (SNR) for the measurements of X-ray reflectivity and grazing incidence diffraction by controlling the X-ray path within the liquid in the cell and easy operation for variable liquid temperature. This very low-cost temperature-controlled setup, developed in our laboratory, can perform in situ X-ray measurements at various temperature ranges—starting from around 4°C up to 70°C which is very relevant to study the phase transition temperature of the lipids constituting the cell membranes. The detailed mechanical design of the cell and electrical control mechanism of the temperature of the liquid inside the cell has been discussed here. One such X-ray reflectivity measurement is shown here to express the capability of the cell for the study of the solid-supported bilayer sample composed of dipalmitoyl phosphocholine lipid at two different temperatures, below its phase transition temperature.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141525012","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}
Pub Date : 2024-06-28DOI: 10.1134/s0020441224700192
S. V. Korotkov, A. L. Zhmodikov, D. A. Korotkov
Abstract
The results of comparative studies of generators of high-power submicrosecond rectangular pulses are presented. The switch in these generators is made in the form of a transistor block with a transformer control circuit. A block consisting of ten transistors connected in series is described, which is able to commutate into a load of 150 Ω rectangular current pulses with an amplitude of 50 A, a duration of up to 1 μs, and rise and fall times of less than 50 ns at a repetition rate of 2 kHz. The possibility of increasing the switched power by increasing the power voltage up to tens of kilovolts is determined.
{"title":"Transistor Generators of High-Power Rectangular Pulses with Submicrosecond Duration","authors":"S. V. Korotkov, A. L. Zhmodikov, D. A. Korotkov","doi":"10.1134/s0020441224700192","DOIUrl":"https://doi.org/10.1134/s0020441224700192","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The results of comparative studies of generators of high-power submicrosecond rectangular pulses are presented. The switch in these generators is made in the form of a transistor block with a transformer control circuit. A block consisting of ten transistors connected in series is described, which is able to commutate into a load of 150 Ω rectangular current pulses with an amplitude of 50 A, a duration of up to 1 μs, and rise and fall times of less than 50 ns at a repetition rate of 2 kHz. The possibility of increasing the switched power by increasing the power voltage up to tens of kilovolts is determined.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141525111","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}
Pub Date : 2024-06-28DOI: 10.1134/s0020441224700222
A. I. Meshcheryakov, I. A. Grishina
Abstract
A technique is proposed for reconstructing the electron temperature profile under conditions when the integral absorption coefficient of electron cyclotron emission (ECE) is less than unity. Numerical simulations of plasma ECE were performed for the L-2M stellarator in the ohmic heating regime. It is shown that the radiation temperature profiles recovered from the ECE diagnostics data in the ohmic heating regime require considerable correction. The profile width turns out to be smaller than the width of the true temperature profile, and the on-axis plasma temperature is underestimated by ~30%. A new method is proposed for the relative calibration of ECE diagnostics channels in the ohmic heating regime. The resulting calibration coefficients can be used to measure the plasma temperature in the electron cyclotron resonance heating regime.
{"title":"Recovery of Plasma Electron Temperature Profile from Data of ECE Diagnostics and Relative Calibration of Its Frequency Channels in Ohmic Heating Regime at the L-2M Stellarator","authors":"A. I. Meshcheryakov, I. A. Grishina","doi":"10.1134/s0020441224700222","DOIUrl":"https://doi.org/10.1134/s0020441224700222","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>A technique is proposed for reconstructing the electron temperature profile under conditions when the integral absorption coefficient of electron cyclotron emission (ECE) is less than unity. Numerical simulations of plasma ECE were performed for the L-2M stellarator in the ohmic heating regime. It is shown that the radiation temperature profiles recovered from the ECE diagnostics data in the ohmic heating regime require considerable correction. The profile width turns out to be smaller than the width of the true temperature profile, and the on-axis plasma temperature is underestimated by ~30%. A new method is proposed for the relative calibration of ECE diagnostics channels in the ohmic heating regime. The resulting calibration coefficients can be used to measure the plasma temperature in the electron cyclotron resonance heating regime.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141525113","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}
Pub Date : 2024-06-28DOI: 10.1134/s0020441224700167
V. V. Kolobov, M. B. Barannik
Abstract—
A channel for measuring the magnetic flux density based on four integrated Hall-effect magnetic sensors (IHMSs) is described. Built-in thermal compensation and dynamic offset cancellation circuits of IHMSs do not eliminate the sensor’s magnetic sensitivity drift due to the thermomechanical packaging stresses that causes an output-voltage offset. The placement of the sensors in a thermostatically controlled cell, as well as the design and circuit solutions related to the spatial orientation of the sensors relative to the magnetic induction vector and to the IHMS output voltage processing algorithm, made it possible to minimize the instability and increase the signal-to-noise ratio of the channel’s ADC input voltage. The design and operation of the hardware–software-based PI controller that regulates the thermostatted cell temperature are considered. The developed channel is used to measure the magnetic-field flux density of the magnetic analyzer of the mass-spectrometric system for isotopic analysis of noble gases and provides the following specifications: the measurement range is ±512 mT; the bandwidth is 0–4 Hz; the noise-free code resolution of the channel is 16.3 bits; the peak-to-peak value of the equivalent input magnetic noise in the bandwidth is 0.012 mT; and the equivalent input long-term drift of measurements is no more than 0.08 mT within 48 h.
{"title":"A Thermostatted Magnetometer Channel","authors":"V. V. Kolobov, M. B. Barannik","doi":"10.1134/s0020441224700167","DOIUrl":"https://doi.org/10.1134/s0020441224700167","url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract—</h3><p>A channel for measuring the magnetic flux density based on four integrated Hall-effect magnetic sensors (IHMSs) is described. Built-in thermal compensation and dynamic offset cancellation circuits of IHMSs do not eliminate the sensor’s magnetic sensitivity drift due to the thermomechanical packaging stresses that causes an output-voltage offset. The placement of the sensors in a thermostatically controlled cell, as well as the design and circuit solutions related to the spatial orientation of the sensors relative to the magnetic induction vector and to the IHMS output voltage processing algorithm, made it possible to minimize the instability and increase the signal-to-noise ratio of the channel’s ADC input voltage. The design and operation of the hardware–software-based PI controller that regulates the thermostatted cell temperature are considered. The developed channel is used to measure the magnetic-field flux density of the magnetic analyzer of the mass-spectrometric system for isotopic analysis of noble gases and provides the following specifications: the measurement range is ±512 mT; the bandwidth is 0–4 Hz; the noise-free code resolution of the channel is 16.3 bits; the peak-to-peak value of the equivalent input magnetic noise in the bandwidth is 0.012 mT; and the equivalent input long-term drift of measurements is no more than 0.08 mT within 48 h.</p>","PeriodicalId":587,"journal":{"name":"Instruments and Experimental Techniques","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141525117","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}