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Zelener BB, Vilshanskaya EV, Morozov NV, Saakyan SA, Bobrov AA, Sautenkov VA, Zelener BV. Steady-State Ultracold Plasma Created by Continuous Photoionization of Laser Cooled Atoms. PHYSICAL REVIEW LETTERS 2024; 132:115301. [PMID: 38563955 DOI: 10.1103/physrevlett.132.115301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/10/2024] [Accepted: 02/20/2024] [Indexed: 04/04/2024]
Abstract
In this Letter we discuss our approach that makes possible creation of the steady-state ultracold plasma having various densities and temperatures by means of continuous two-step optical excitation of calcium atoms in the magneto-optical trap. A strongly coupled ultracold plasma can be used as an excellent test platform for studying many-body interactions associated with various plasma phenomena. The parameters of the plasma are studied using laser-induced fluorescence of calcium ions. The experimental results are well described by a simple theoretical model involving equilibration of the continuous source of charged particles by the hydrodynamical ion outflux and three-body recombination. The ultracold plasma with the peak ion density of 2.7×10^{6} cm^{-3} and the minimum electron temperature near 2 K has been prepared. Our steady-state approach in combination with the strong magnetic confinement of the plasma will make it possible to reach extremely strong coupling in such system.
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Affiliation(s)
- B B Zelener
- Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412, Russia
| | - E V Vilshanskaya
- Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412, Russia
| | - N V Morozov
- Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412, Russia
| | - S A Saakyan
- Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412, Russia
| | - A A Bobrov
- Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412, Russia
| | - V A Sautenkov
- Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412, Russia
| | - B V Zelener
- Joint Institute for High Temperatures, Russian Academy of Sciences, Moscow 125412, Russia
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Wang J, Yang L, Zhou J, Yao L, Han Y, Zhou H, Yu S, Guo B. The design and construction of divertor primary heat transfer system for EAST Tokamak. FUSION ENGINEERING AND DESIGN 2023. [DOI: 10.1016/j.fusengdes.2023.113703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/30/2023]
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3
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Experimental investigation of the flowing lithium limiter. Part 1. The spreading characteristics of lithium on solid substrate without an external magnetic field. FUSION ENGINEERING AND DESIGN 2023. [DOI: 10.1016/j.fusengdes.2023.113489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
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4
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Maan A, Boyle D, Majeski R, Banerjee S, Franscisquez M, Kaita R, Wilkie G, Capecchi W, Kubota S, Hansen C, Soukhanovskii V. Improved neutral and plasma density control with increasing lithium wall coatings in the Lithium Tokamak Experiment- β (LTX- β ). NUCLEAR MATERIALS AND ENERGY 2023. [DOI: 10.1016/j.nme.2023.101408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/12/2023]
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5
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Study of Plasma Interaction with Liquid Lithium Multichannel Capillary Porous Systems in SCU-PSI. Processes (Basel) 2022. [DOI: 10.3390/pr10091852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
In this paper, an embedded multichannel capillary porous system (EM-CPS) was designed and fabricated with 304 stainless steel using the laser ablation method. The EM-CPS revealed its excellent ability to wick liquid lithium to its surface effectively. The interaction between Li-prefilled EM-CPS and plasma was studied, and the results showed that the surface temperature decreased by ~140 °C compared with the results of the experiment of EM-CPS without lithium filling. Additionally, EM-CPS displayed a better heat transfer performance and stronger radiation loss of the vapor cloud than the traditional woven tungsten-based meshes. In addition, the drift of the lithium vapor cloud center was found during plasma irradiation and led to a decrease in the intensity of the Li 670.78 nm emission line detected by the spectrometer at the observation point. When the thermal load deposited on the sample surface is reinforced by increasing the magnetic field, the rise in surface temperature is restrained due to the enhanced heat dissipation capability of lithium. SEM images of irradiated samples showed that the 304 stainless steel-based EM-CPS has corrosion problems due to the interaction between liquid lithium and argon plasma, but it still showed good plasma-facing characteristics. These findings provide a reference for further studies of embedded multichannel CPSs with plasma-facing components (PFCs) in linear plasma devices and tokamaks in the future.
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Zheng J, Qin J, Lu K, Xu M, Duan X, Xu G, Hu J, Gong X, Zang Q, Liu Z, Wang L, Ding R, Chen J, Li P, Xue L, Cai L, Song Y. Recent progress in Chinese fusion research based on superconducting tokamak configuration. Innovation (N Y) 2022; 3:100269. [PMID: 35815072 PMCID: PMC9256834 DOI: 10.1016/j.xinn.2022.100269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 06/08/2022] [Indexed: 11/24/2022] Open
Abstract
Fusion energy is a promising source of clean energy, which could solve energy shortages and environmental pollution. Research into controlled fusion energy has been ongoing for over half a century. China has created a clear roadmap for magnetic confinement fusion development, where superconducting tokamaks will be used in commercial fusion reactors. The Experimental Advanced Superconducting Tokamak (EAST) is the world’s first fully superconducting tokamak with upper and lower divertors, which aims at long-pulse, steady-state, H-mode operation, and 101-s H-mode discharge had been achieved. In 2007, China joined the International Thermonuclear Experimental Reactor (ITER) and became one of its seven members. Thirteen procurement packages are undertaken by China, covering superconducting magnets, power supplies, plasma-facing components (PFCs), diagnostics, etc. To bridge the gap between the ITER and fusion demonstration power plants (DEMOs), China is planning to build the Chinese Fusion Engineering Testing Reactor (CFETR) to demonstrate related technologies and physics models. The engineering design of the CFETR was completed in 2020, and Comprehensive Research Facilities for Fusion Technology (CRAFT) are being constructed to explore the key technologies used in the CFETR. Fusion energy is a promising source of clean energy Tokamak is the most widely studied magnetic confinement fusion device China built the world’s first fully superconducting tokamak -EAST China is one of the seven members of the ITER project CFETR engineering design has been completed, and its R&D is ongoing
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Cao B, Bi H, Yu Y, Cao H, Zhou Z, Zuo G. Development and implementation of Divertor Fast Particles Injection for EAST tokamak. FUSION ENGINEERING AND DESIGN 2022. [DOI: 10.1016/j.fusengdes.2022.113101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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8
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High Transient-Thermal-Shock Resistant Nanochannel Tungsten Films. NANOMATERIALS 2021; 11:nano11102663. [PMID: 34685104 PMCID: PMC8537346 DOI: 10.3390/nano11102663] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2021] [Revised: 10/01/2021] [Accepted: 10/07/2021] [Indexed: 12/02/2022]
Abstract
Developing high-performance tungsten plasma-facing materials for fusion reactors is an urgent task. In this paper, novel nanochannel structural W films prepared by magnetron sputtering deposition were irradiated using a high-power pulsed electron beam or ion beam to study their edge-localized modes, such as transient thermal shock resistance. Under electron beam irradiation, a 1 μm thick nanochannel W film with 150 watt power showed a higher absorbed power density related cracking threshold (0.28–0.43 GW/m2) than the commercial bulk W (0.16–0.28 GW/m2) at room temperature. With ion beam irradiation with an energy density of 1 J/cm2 for different pulses, the bulk W displayed many large cracks with the increase of pulse number, while only micro-crack networks with a width of tens of nanometers were found in the nanochannel W film. For the mechanism of the high resistance of nanochannel W films to transient thermal shock, a residual stress analysis was made by Grazing-incidence X-ray diffraction (GIXRD), and the results showed that the irradiated nanochannel W films had a much lower stress than that of the irradiated bulk W, which indicates that the nanochannel structure can release more stress, due to its special nanochannel structure and ability for the annihilation of irradiation induced defects.
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9
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Wall conditioning and ELM mitigation with boron nitride powder injection in KSTAR. NUCLEAR MATERIALS AND ENERGY 2021. [DOI: 10.1016/j.nme.2021.101043] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Oyarzabal E, Tabarés F. Strongly temperature-dependent, anomalous secondary electron emission of liquid lithium surfaces exposed to a plasma. NUCLEAR MATERIALS AND ENERGY 2021. [DOI: 10.1016/j.nme.2021.100966] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Peng L, Sun J, Sun Z, Gao F, Bonnin X, Liu J. Numerical simulation study of impurity B transport during real-time B powder injection in EAST. NUCLEAR MATERIALS AND ENERGY 2021. [DOI: 10.1016/j.nme.2021.100937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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de Castro A, Moynihan C, Stemmley S, Szott M, Andruczyk D, Ruzic D. Exploration of Sn70Li30 alloy as possible material for flowing liquid metal plasma facing components. NUCLEAR MATERIALS AND ENERGY 2020. [DOI: 10.1016/j.nme.2020.100829] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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13
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Maingi R, Hu JS, Sun Z, Diallo A, Tritz K, Qian YZ, Xu W, Zuo GZ, Li CL, Huang M, Ye Y, Bortolon A, Gilson EP, Lunsford R, Mansfield DK, Nagy A, Qian JP, Gong XZ. ELM Suppression by Boron Powder Injection and Comparison with Lithium Powder Injection on EAST. JOURNAL OF FUSION ENERGY 2020. [DOI: 10.1007/s10894-020-00256-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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15
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Liu Y, Yang Y, Huang J, Yang Y, Wang F. An intelligent identification method of the edge coherent mode in EAST. FUSION ENGINEERING AND DESIGN 2019. [DOI: 10.1016/j.fusengdes.2019.05.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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16
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Experiments of continuously and stably flowing lithium limiter in EAST towards a solution for the power exhaust of future fusion devices. NUCLEAR MATERIALS AND ENERGY 2019. [DOI: 10.1016/j.nme.2018.12.017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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17
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Real-time reduction of tungsten impurity influx using lithium powder injection in EAST. FUSION ENGINEERING AND DESIGN 2018. [DOI: 10.1016/j.fusengdes.2018.09.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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18
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Numerical simulation of Li pellet ablation in the H-mode pedestal region. FUSION ENGINEERING AND DESIGN 2018. [DOI: 10.1016/j.fusengdes.2018.04.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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19
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Xu W, Hu J, Zuo G, Sun Z, Lunsford R, Meng X, Huang M. A new developed in-between shots lithium evaporation coating system for improving plasma performance in EAST. FUSION ENGINEERING AND DESIGN 2018. [DOI: 10.1016/j.fusengdes.2018.05.061] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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20
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Zhao D, Li C, Hu Z, Feng C, Xiao Q, Hai R, Liu P, Sun L, Wu D, Fu C, Liu J, Farid N, Ding F, Luo GN, Wang L, Ding H. Remote in situ laser-induced breakdown spectroscopic approach for diagnosis of the plasma facing components on experimental advanced superconducting tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:073501. [PMID: 30068087 DOI: 10.1063/1.5024848] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The diagnosis of the fuel retention and impurity deposition on the plasma facing components (PFCs) is very important for monitoring plasma-wall interactions and improving the performance of long-pulse operation for tokamak devices. In this study, a remote in situ laser-induced breakdown spectroscopic (RIS-LIBS) system has been developed to be an effective and routine method for the diagnosis of the composition of the PFCs on Experimental Advanced Superconducting Tokamak (EAST). The RIS-LIBS system can be operated between EAST discharges via a remote network control system. This allows a flexible diagnosis for the PFCs at a specific EAST discharge operation or under planned plasma scenarios according to the experimental requirement. Measurements on the fuel retention and impurity deposition of the PFCs have been performed for the test of the RIS-LIBS system, and the depth resolution and the lateral resolution of the RIS-LIBS system have been achieved to be ∼100 nm and ∼3.0 mm, respectively. For the test of detectable elements, the fuel (deuterium) and impurities have been detected and identified clearly. In addition, the measurement of fuel abundance on the first wall as a function of the days of EAST deuterium plasma discharges has been carried out for the first time. These results well manifest a significant prospect of the RIS-LIBS for the diagnosis of the PFCs in the upcoming fusion devices like China Fusion Engineering Test Reactor (CFETR) and ITER.
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Affiliation(s)
- Dongye Zhao
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - Cong Li
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - Zhenhua Hu
- Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China
| | - Chunlei Feng
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - Qingmei Xiao
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - Ran Hai
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - Ping Liu
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - Liying Sun
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - Ding Wu
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - Cailong Fu
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - Jiamin Liu
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - Nazar Farid
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
| | - Fang Ding
- Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China
| | - Guang-Nan Luo
- Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China
| | - Liang Wang
- Institute of Plasma Physics, Chinese Academy of Sciences, P.O. Box 1126, Hefei, Anhui 230031, People's Republic of China
| | - Hongbin Ding
- School of Physics, Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Chinese Ministry of Education, Dalian University of Technology, Dalian 116024, People's Republic of China
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21
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Present State of Chinese Magnetic Fusion Development and Future Plans. JOURNAL OF FUSION ENERGY 2018. [DOI: 10.1007/s10894-018-0165-2] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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22
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Yang JC, Qi TY, Ren DW, Liu BQ, Ni MJ. Surface waves of liquid metal film flow under the influence of spanwise magnetic field. FUSION ENGINEERING AND DESIGN 2018. [DOI: 10.1016/j.fusengdes.2018.03.021] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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23
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Impact of wall materials and seeding gases on the pedestal and on core plasma performance. NUCLEAR MATERIALS AND ENERGY 2017. [DOI: 10.1016/j.nme.2017.01.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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24
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Li N, Sun J, Wang Z, Xu X, Sun Z, Wang L, Hu J, Wang D. Numerical investigation on lithium transport in the edge plasma of EAST real-time- Li-injection experiments in the frame of BOUT++. NUCLEAR MATERIALS AND ENERGY 2017. [DOI: 10.1016/j.nme.2016.12.009] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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25
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Zhou F, Ming T, Wang Y, Wang Z, Long F, Zhuang Q, Li G, Liang Y, Gao X. Development of a high-speed vacuum ultraviolet (VUV) imaging system for the Experimental Advanced Superconducting Tokamak. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2017; 88:073505. [PMID: 28764528 DOI: 10.1063/1.4991856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A high-speed vacuum ultraviolet (VUV) imaging system for edge plasma studies is being developed on the Experimental Advanced Superconducting Tokamak (EAST). Its key optics is composed of an inverse type of Schwarzschild telescope made of a set of Mo/Si multilayer mirrors, a micro-channel plate (MCP) equipped with a P47 phosphor screen and a high-speed camera with CMOS sensors. In order to remove the contribution from low-energy photons, a Zr filter is installed in front of the MCP detector. With this optics, VUV photons with a wavelength of 13.5 nm, which mainly come from the line emission from intrinsic carbon (C vi: n = 4-2 transition) or the Ly-α line emission from injected Li iii on the EAST, can be selectively measured two-dimensionally with both high temporal and spatial resolutions. At present, this system is installed to view the plasma from the low field side in a horizontal port in the EAST. It has been operated routinely during the 2016 EAST experiment campaign, and the first result is shown in this work. To roughly evaluate the system performance, synthetic images are created. And it indicates that this system mainly measures the edge localized emissions by comparing the synthetic images and experimental data.
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Affiliation(s)
- Fan Zhou
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Tingfeng Ming
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Yumin Wang
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Zhijun Wang
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Feifei Long
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Qing Zhuang
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Guoqiang Li
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Yunfeng Liang
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
| | - Xiang Gao
- Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031, China
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Maingi R, Canik J, Bell R, Boyle D, Diallo A, Kaita R, Kaye S, LeBlanc B, Sabbagh S, Scotti F, Soukhanovskii V. Effect of progressively increasing lithium conditioning on edge transport and stability in high triangularity NSTX H-modes. FUSION ENGINEERING AND DESIGN 2017. [DOI: 10.1016/j.fusengdes.2016.06.058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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27
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Arredondo Parra R, Moreno Quicios R, Ploeckl B, Birkenmeier G, Herrmann A, Kocsis G, Laggner FM, Lang PT, Lunt T, Macian-Juan R, Rohde V, Sellmair G, Szepesi T, Wolfrum E, Zeidner W, Neu R. A compact lithium pellet injector for tokamak pedestal studies in ASDEX Upgrade. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:023508. [PMID: 26931850 DOI: 10.1063/1.4942122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Experiments have been performed at ASDEX Upgrade, aiming to investigate the impact of lithium in an all-metal-wall tokamak and attempting to enhance the pedestal operational space. For this purpose, a lithium pellet injector has been developed, capable of injecting pellets carrying a particle content ranging from 1.82 × 10(19) atoms (0.21 mg) to 1.64 × 10(20) atoms (1.89 mg). The maximum repetition rate is about 2 Hz. Free flight launch from the torus outboard side without a guiding tube was realized. In such a configuration, angular dispersion and speed scatter are low, and a transfer efficiency exceeding 90% was achieved in the test bed. Pellets are accelerated in a gas gun; hence special care was taken to avoid deleterious effects by the propellant gas pulse. Therefore, the main plasma gas species was applied as propellant gas, leading to speeds ranging from 420 m/s to 700 m/s. In order to minimize the residual amount of gas to be introduced into the plasma vessel, a large expansion volume equipped with a cryopump was added into the flight path. In view of the experiments, an optimal propellant gas pressure of 50 bars was chosen for operation, since at this pressure maximum efficiency and low propellant gas flux coincide. This led to pellet speeds of 585 m/s ± 32 m/s. Lithium injection has been achieved at ASDEX Upgrade, showing deep pellet penetration into the plasma, though pedestal broadening has not been observed yet.
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Affiliation(s)
- R Arredondo Parra
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
| | - R Moreno Quicios
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
| | - B Ploeckl
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
| | - G Birkenmeier
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
| | - A Herrmann
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
| | - G Kocsis
- Wigner RCP Institute for Particle and Nuclear Physics, 1121 Budapest, Hungary
| | - F M Laggner
- Institute of Applied Physics, TU Wien, Fusion@ OAW, Wiedner Hauptstr. 8-10, 1040 Vienna, Austria
| | - P T Lang
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
| | - T Lunt
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
| | - R Macian-Juan
- Technische Universität München, 85748 Garching, Germany
| | - V Rohde
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
| | - G Sellmair
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
| | - T Szepesi
- Wigner RCP Institute for Particle and Nuclear Physics, 1121 Budapest, Hungary
| | - E Wolfrum
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
| | - W Zeidner
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
| | - R Neu
- Max Planck Institut für Plasmaphysik, Boltzmannstrasse 2, 85748 Garching, Germany
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Zhang XH, Liu AD, Zhou C, Hu JQ, Wang MY, Yu CX, Liu WD, Li H, Lan T, Xie JL. Influence of lithium coating on the optics of Doppler backscatter system. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2015; 86:103503. [PMID: 26520951 DOI: 10.1063/1.4932185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
This paper presents the first investigation of the effect of lithium coating on the optics of Doppler backscattering. A liquid lithium limiter has been applied in the Experimental Advanced Superconducting Tokamak (EAST), and a Doppler backscattering has been installed in the EAST. A parabolic mirror and a flat mirror located in the vacuum vessel are polluted by lithium. An identical optical system of the Doppler backscattering is set up in laboratory. The power distributions of the emission beam after the two mirrors with and without lithium coating (cleaned before and after), are measured at three different distances under four incident frequencies. The results demonstrate that the influence of the lithium coating on the power distributions are very slight, and the Doppler backscattering can work normally under the dosage of lithium during the 2014 EAST campaign.
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Affiliation(s)
- X H Zhang
- Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - A D Liu
- Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - C Zhou
- Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - J Q Hu
- Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - M Y Wang
- Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - C X Yu
- Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - W D Liu
- Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - H Li
- Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - T Lan
- Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - J L Xie
- Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026, China
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Peng L, Wu J, Ding F, Zhao S, Qiao L, Mao H, Wang P, Luo GN. Effect of Li on Safety of Cu Components for EAST. JOURNAL OF FUSION ENERGY 2015. [DOI: 10.1007/s10894-015-9906-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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