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第四代ECR(电子回旋共振)离子源高场Nb_(3)Sn磁体1/2长度样机的研制

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Acta Mechanica Sinica 2024年第4期40卷 61-77页

作者：孙良亭吴巍吴北民陈玉泉朱丽欧贤金郑石钧梅恩铭关明智辛灿杰王旭东卢旺任文辉赵红卫 institute of Modern Physics Chinese Academy of SciencesLanzhou730000China School of nuclear Science and Technology University of Chinese Academy of SciencesBeijing100049China Advanced Energy Science and Technology Guangdong laboratory Huizhou516000China

中国科学院近代物理研究所正在研发第四代ECR(电子回旋共振)离子源FECR(first 4th generation ECR ion source).以20 kW/45 GHz微波加热运行为目标,需要研制Nb_(3)Sn超导磁体以实现对所加热等离子体的有效磁场约束.作为首台采用Nb_(3)S... 详细信息

中国科学院近代物理研究所正在研发第四代ECR(电子回旋共振)离子源FECR(first 4th generation ECR ion source).以20 kW/45 GHz微波加热运行为目标,需要研制Nb_(3)Sn超导磁体以实现对所加热等离子体的有效磁场约束.作为首台采用Nb_(3)Sn超导磁体技术的ECR离子源,FECR的主磁场线圈由4套独立的轴向螺线管线圈与1套径向六极线圈所构成,且均采用单股Nb_(3)Sn线绕制而成,这给线圈的加工、冷体装配、磁体的失超保护等环节带来一系列挑战.为使磁体能在高场、高应力作用下安全稳定运行,项目采用基于铝壳体结构与bladder&key的预紧应力控制技术,完成了一套半尺寸冷体样机的研发.该样机已完成4.2 K低温测试.本项研究的核心关键问题与挑战是如何在复杂的高精度机械装配与高电流强磁场励磁过程中实现对易碎Nb_(3)Sn导线的有效保护.本篇文章中,我们将阐述如何设计、研制、装配及测试工作于复杂磁场与应力环境的高性能Nb_(3)Sn六极磁铁.针对于单个六极线圈的测试,我们设计研发了一种称为“Mirror”结构的测试工装.论文中会详细论述基于壳层结构与bladder&key的装配预紧技术在半尺寸样机上的应用效果.同时,论文对在半尺寸样机上观察到的强烈磁通跳跃现象和它对失超探测保护的严峻挑战问题及相关解决或规避方案进行相关论述.

关键词：超导磁体磁通跳跃电子回旋共振绕制测试工装机械装配壳层结构离子源

Constraints on symmetry energy and n/p effective mass splitting with improved quantum molecular dynamics model

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nuclear Science and Techniques 2013年第5期24卷 13-18页

作者： ZHANG Yingxun LI Zhuxia ZHAO Kai LIU Hang TSANG M B China institute of Atomic Energy national superconducting cyclotron laboratory Michigan State University Texas Advanced Computing Center University of TexasAustin

A new version of improved quantum molecular dynamics model that includes standard Skyrme interactions has been *** on the new code,four commonly used parameter sets,SLy4,SkI2,SkM*and Gs are adopted in the improved quantum molecular dynamics model and the isospin sensitive observables,namely isospin transport ratios,single and double ratios of the yields of neutrons and protons are *** isospin transport ratios are strongly sensitive to the slope of symmetry energy,and are not very sensitive to the nucleon effective mass *** the other hand,the high energy neutrons and protons yields ratios from reactions at different incident energies provide a good observable to the momentum dependence of nucleon effective mass *** comparing our calculations with the data,we find that the constrained L value(the slope of density dependence of symmetry energy) is about ~46 MeV when the Skyrme type interaction is considered in transport models,and the isospin diffusion data prefer to mn*>mp*,but it is not a strong constraint with deep χ2minimum.

关键词：量子分子动力学模型核子有效质量对称能 Skyrme相互作用分裂密度依赖性入射能量运输模型

Repeating fast radio bursts: Coherent circular polarization by bunches

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Science China(Physics,Mechanics & Astronomy) 2022年第8期65卷 148-157页

作者： Wei-Yang Wang Jin-Chen Jiang Jiguang Lu Heng Xu Jiangwei Xu Kejia Lee Jifeng Liu Renxin Xu School of Physics and State Key laboratory of nuclear Physics and Technology Peking UniversityBeijing100871China Kavli institute for Astronomy and astrophysics Peking UniversityBeijing100871China CAS Key laboratory of FAST National Astronomical ObservatoriesChinese Academy of SciencesBeijing100101China Guizhou Radio Astronomy Observatory Chinese Academy of SciencesGuiyang550025China Key laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing100101China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing100049China

Fast radio bursts(FRBs) are millisecond-duration signals that are highly dispersed at distant galaxies. However, the physical origin of FRBs is still unknown. Coherent curvature emission by bunches, e.g., powered by starquakes, has already been proposed for repeating FRBs. It has the nature of understanding narrowband radiation exhibiting time-frequency drifting. Recently, a highly active FRB source, i.e., FRB 20201124A, was reported to enter a newly active episode and emit at least some highly circular-polarized bursts. In this study, we revisit the polarized FRB emission, particularly investigating the production mechanisms of a highly circular polarization(CP) by deriving the intrinsic mechanism and propagative effect. The intrinsic mechanisms of invoking charged bunches are approached with radiative coherence. Consequently, a highly CP could naturally be explained by the coherent summation of outcome waves, generated or scattered by bunches, with different phases and electric vectors. Different kinds of evolutionary trajectories are found on the Poincaré sphere for the bunch-coherent polarization, and this behavior could be tested through future observations. cyclotron resonance can result in the absorption of R-mode photons at a low altitude region of the magnetosphere, and an FRB should then be emitted from a high-altitude region if the waves have strong linear polarization. Circularly polarized components could be produced from Faraday conversion exhibiting a λ-oscillation, but the average CP fraction depends only on the income wave, indicating a possibility of a highly circular-polarized income wave. The analysis could be welcome if extremely high(e.g., almost 100%) CP from repeating FRBs is detected in the future. Finally, the production of a bulk of energetic bunches in the pulsar-like magnetosphere is discussed, which is relevant to the nature of the FRB central engine.

关键词： fast radio burst radiation mechanism neutron stars

Proton Spectroscopic Factors Deduced from Helium-3 Global Phenomenological and Microscopic Optical Model Potentials

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Chinese Physics Letters 2014年第9期31卷 36-39页

作者：李晓菁庞丹阳韩银录曾敏儿 RIKEN Nishina Center Saitama 351-0198 Japan national superconducting cyclotron laboratory and Department o-f Physics and Astronomy Michigan State University Michigan 48824 USA School of Physics and nuclear Energy Engineering Beihang University Beijing 100191 International Research Center for Nuclei and-i3articles in the Cosmos Beihang University Beijing 100191 China institute of Atomic Energy Beijing 102413

Global phenomenological GDP08 and microscopic hefium-3 optical model potentials have been recently derived. We evaluate these two potential sets by comparing the elastic scattering data of 25 MeV 3He on 160, 180, 19F, 23Na, 24Mg, 25Mg, 26Mg, 27A1, 28Si, 30Si, 31p, 32S, 34S, 35Cl, 3761, and 39K isotopes. Using the deuteron angular distributions calculated with the distorted wave Born approximation model, we extract the ground-state proton spectroscopic factors from （3He, d） reactions on the same set of nuclei. The extracted proton spectroscopic factors are compared with the large-basis shell-model calculations.

关键词： Helium

Constraints On Symmetry Energy from Sn+Sn collisions

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Constraints On Symmetry Energy from Sn+Sn collisions

Observation of Central Toroidal Rotation Induced by ICRF on EAST

International workshop on nuclear dynamics in heavy-ion reactions and the symmetry energy

作者：曾敏兒連致標张英逊 P.Danielewicz M.Famiano 李祝霞 A.W.Steiner joint institute of nuclear astrophysics and national superconducting cyclotron laboratory Michigan State UniversityEast LansingMI 48824 USA Physics and Astronomy Department Michigan State UniversityEast LansingMI 48824 USA China institute of Atomic Energy Physics Department Western Michigan UniversityKalamazooMIUSA.

＜正＞Constraints on the Equation of State for symmetric matter（equal neutron and proton numbers） have been extracted from energetic collisions of heavy ions over a range of *** of neutron-deficient and neutron-rich heavy ions now provide initial constraints on the EoS of neutron-rich matter at sub-saturation densities from isospin diffusions and neutron proton *** constraints are compared to other available constraints from nuclear structures and masses and to constraints obtained at supra-normal densities.

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Plasma Science and Technology 2016年第2期18卷 114-119页

作者：潘夏云王福地张新军吕波陈俊李颖颖符佳石跃江余羿叶民友万宝年 School of nuclear Science and Technology University of Science and Technology of China institute of Plasma Physics Chinese Academy of Sciences Hefei Science Center Chinese Academy of Sciences Department of nuclear Engineering Seoul National University

Core plasma rotation of both L-mode and H-mode discharges with ion cyclotron range of frequency（ICRF） minority heating（MH） scheme was measured with a tangential X-ray imaging crystal spectrometer on EAST（Experimental Advanced superconducting Tokamak）.Cocurrent central impurity toroidal rotation change was observed in ICRF-heated L-and H-mode *** increment as high as 30 km/s was generated at ~1.7 MW ICRF *** results showed similar trend as the Rice scaling but with significant scattering,especially in L-mode *** varied the plasma current,toroidal field and magnetic configuration individually to study their effect on L-mode plasma rotation,while keeping the other major plasma parameters and heating unchanged during the *** was found that larger plasma current could induce plasma rotation more efficiently.A scan of the toroidal magnetic field indicated that the largest rotation was obtained for on-axis ICRF heating.A comparison between lower-single-null（LSN）and double-null（DN） configurations showed that LSN discharges rendered a larger rotation change for the same power input and plasma parameters.

关键词： central toroidal rotation ICRF flow drive minority heating X-ray imaging crystal spectrometer

Dense matter with eXTP

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Science China(Physics,Mechanics & Astronomy) 2019年第2期62卷 28-44页

作者： Anna L.Watts WenFei Yu Juri Poutanen Shu Zhang Sudip Bhattacharyya Slavko Bogdanov Long Ji Alessandro Patruno Thomas E.Riley Pavel Bakala Altan Baykal Federico Bernardini Ignazio Bombaci Edward Brown Yuri Cavecchi Deepto Chakrabarty Jér?me Chenevez Nathalie Degenaar Melania Del Santo Tiziana Di Salvo Victor Doroshenko Maurizio Falanga Robert D.Ferdman Marco Feroci Angelo F.Gambino MingYu Ge Svenja K.Greif Sebastien Guillot Can Gungor Dieter H.Hartmann Kai Hebeler Alexander Heger Jeroen Homan Rosario Iaria Jean in 't Zand Oleg Kargaltsev Aleksi KurkelaTheoretical Physics Department CERN XiaoYu Lai Ang Li XiangDong Li ZhaoSheng Li Manuel Linares FangJun Lu Simin Mahmoodifar Mariano Méndez M.Coleman Miller Sharon Morsink Joonas N?ttil? Andrea Possenti Chanda Prescod-Weinstein JinLu Qu Alessandro Riggio Tuomo Salmi Andrea Sanna Andrea Santangelo Hendrik Schatz Achim Schwenk LiMing Song Eva?rámková Benjamin Stappers Holger Stiele Tod Strohmayer Ingo Tews Laura Tolos Gabriel T?r?k David Tsang Martin Urbanec Andrea Vacchi RenXin Xu YuPeng Xu Silvia Zane GuoBao Zhang ShuangNan Zhang WenDa Zhang ShiJie Zheng Xia Zhou Anton Pannekoek institute for Astronomy University of Amsterdam Shanghai Astronomical Observatory Tuorla Observatory Department of Physics and Astronomy University of Turku Nordita KTH Royal Institute of Technology and Stockholm University institute of High Energy Physics Chinese Academy Sciences Tata institute of Fundamental Research Columbia astrophysics laboratory Columbia University Institut für Astronomie und Astrophysik Tübingen Universit?t Tübingen Leiden Observatory Leiden University Research Center for Computational Physics and Data Processing Silesian University in Opava Physics Department Middle East Technical University INAF Osservatorio Astronomico di Roma New York University Abu Dhabi Dipartimento di Fisica Enrico Fermi University of Pisa INFN Italian national institute for nuclear Physics Department of Physics and Astronomy Michigan State University Department of Astrophysical Sciences Princeton University Mathematical Sciences and STAG Research Centre University of Southampton MIT Kavli institute for astrophysics and Space Research DTU Space Technical University of Denmark INAF/IASF Palermo via Ugo La Malfa 153 Universita degli Studi di Palermo Dipartimento di Fisica e Chimica International Space Science institute (ISSI) Faculty of Science University of East Anglia INAF Istituto di Astrofisica e Planetologie Spaziali Institut für Kernphysik Technische Universit?t Darmstadt ExtreMe Matter institute EMMI GSI Helmholtzzentrum für Schwerionenforschung GmbH Instituto de Astrof'?sica Pontificia Universidad Católica de Chile Department of Physics & Astronomy Kinard Lab of Physics Clemson University School of Physics and Astronomy Monash University SRON Netherlands institute for Space Research Department of Physics The George Washington University Faculty of Science and Technology University of Stavanger School of Physics and Mechanical & Electrical Engineering Hubei University of Education Department of Astronomy Xiamen University (Haiyun Campus) School of Astronomy and Space

In this White Paper we present the potential of the Enhanced X-ray Timing and Polarimetry(eXTP) mission for determining the nature of dense matter; neutron star cores host an extreme density regime which cannot be replicated in a terrestrial laboratory. The tightest statistical constraints on the dense matter equation of state will come from pulse profile modelling of accretion-powered pulsars, burst oscillation sources, and rotation-powered pulsars. Additional constraints will derive from spin measurements, burst spectra, and properties of the accretion flows in the vicinity of the neutron star. Under development by an international Consortium led by the institute of High Energy Physics of the Chinese Academy of Sciences, the eXTP mission is expected to be launched in the mid 2020 s.

关键词： neutron X-rays dense matter equation of state

Performance comparison of the two ICRF antennas in EAST

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nuclear Science and Techniques 2016年第2期27卷 1-5页

作者： Hua Yang Cong-Feng Wu Sai Dong Yan-Ping Zhao Xin-Jun Zhang Lei Shang national Synchrotron Radiation laboratory University of Science and Technology of China institute of Plasma Physics Chinese Academy of Sciences

The experimental advanced superconducting Tokamak has two suits of ion cyclotron radio frequency heating systems, in which the two antennas are of different structures. Their performance is assessed and compared by CST microwave studio. The radiating capacity of antennas and the arcing around them are estimated. The impurity release is analyzed by the radio frequency(RF) potential in the plasma sheath. The simulation results show that the radiating capacity for the folded antenna(I-port) is better than those for the double loops antenna(B-port). However,the folded antenna is worse than the double loops antenna in terms of breakdown. Moreover, the impurity production is relevant to spectrum shaping. The RF potential at(0, π,π, 0) phasing with the peak of spectrum k//= 8.5 m^(-1)is lower than the one with other phases. The impurity is reduced obviously when the folded antenna is powered with(0, π, π, 0) phasing.

关键词：环天线性能比较 ICRF 超导托卡马克装置等离子体鞘层辐射能力电位分析微波工作室

Edge localized modes suppression via edge E × B velocity shear induced by RF sheath of ion cyclotron resonance heating in EAST

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Science China(Physics,Mechanics & Astronomy) 2022年第3期65卷 71-76页

作者： XinJun Zhang Chu Zhou XiaoLan Zou TianYang Xia YanLong Li ChengMing Qin XianZu Gong Qing Zang MingHui Li Tao Zhang ShouXin Wang HaiQing Liu Guillaume Urbanczyk Adi Liu YanMing Duan YanPing Zhao JinPing Qian Robert Isaac Pinsker MinYou Ye BaoNian Wan institute of Plasma Physics Chinese Academy of Sciences(ASIPP)Hefei 230031China School of nuclear Sciences and Technology University of Science and Technology of ChinaHefei 230026China CEA IRFMSaint-Paul-les-Durance F-13108France Key laboratory of Optoelectronic Devices and Systems College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China General Atomics San Diego CA 92186-5608USA

The control of large edge localized modes(ELMs) is a critical issue for the successful operation of future burning plasma devices,such as the international thermonuclear experimental reactor(ITER) and China fusion engineering test reactor(CFETR). In this paper, we present a new active and effective means of ELM suppression using ion cyclotron resonant heating(ICRH) on the experimental advanced superconducting tokamak(EAST). We obtained the key role of the external E × B velocity shear near the pedestal top and the scrape-off-layer(SOL) induced by the RF sheath potential of ICRH in ELM suppression. The experimental results showed a positive correlation between the RF sheath and the E × B shear rate in SOL. BOUT++ simulations indicate that increased E × B velocity shear rates in the pedestal and SOL regions promote ELM suppression;thereby, supporting the experimental observations on EAST. These findings suggest a new simple approach to access the ELM suppressed regimes in plasma with low torque input as ITER baseline discharges.

关键词： ion cyclotron resonant heating RF sheath edge localized mode suppression E×B velocity shear