电荷交换复合光谱(Charge e Xchange Recombination Spectroscopy,CXRS)诊断系统主要用于等离子体旋转速度和离子温度的测量。CXRS诊断的另外一个重要应用是通过测量光谱的绝对强度来确定杂质离子的密度,因此需要对系统进行绝对强度标...电荷交换复合光谱(Charge e Xchange Recombination Spectroscopy,CXRS)诊断系统主要用于等离子体旋转速度和离子温度的测量。CXRS诊断的另外一个重要应用是通过测量光谱的绝对强度来确定杂质离子的密度,因此需要对系统进行绝对强度标定。在实验前通过精确校准过且各个波长强度已知的积分球光源对系统进行初步的标定;在实验过程中又利用托卡马克装置中等离子体自身产生的轫致辐射对系统的强度标定进行了进一步的检验。通过比较轫致辐射强度的实验测量值和理论计算值,可以发现两种方法得到的结果虽然存在一定的误差,但是它们的趋势是一致的。实验结果表明,利用轫致辐射进行绝对强度标定是可行的。展开更多
A three-fluid equilibrium plasma with bulk plasma and energetic electrons has been observed on the Xuanlong-50(EXL-50) spherical torus, where the energetic electrons play a crucial role in sustaining the plasma curren...A three-fluid equilibrium plasma with bulk plasma and energetic electrons has been observed on the Xuanlong-50(EXL-50) spherical torus, where the energetic electrons play a crucial role in sustaining the plasma current and pressure. In this study, the equilibrium of a multi-fluid plasma was investigated by analyzing the relationship between the external vertical magnetic field(B_(V)),plasma current(I_(p)), the poloidal ratio(β_(p)) and the Shafranov formula. Remarkably, our research demonstrates some validity of the Shafranov formula in the presence of multi-fluid plasma in EXL-50 spherical torus. This finding holds significant importance for future reactors as it allows for differentiation between alpha particles and background plasma. The study of multi-fluid plasma provides a significant reference value for the equilibrium reconstruction of burning plasma involving alpha particles.展开更多
Charge exchange recombination spectroscopy （CXRS） based on a diagnostic neutral beam （DNB） installed in the HT-7 tokamak is introduced. DNB can provide a 6 A extracted current at 50 kV for 0.1 s in hydrogen. It ca...Charge exchange recombination spectroscopy （CXRS） based on a diagnostic neutral beam （DNB） installed in the HT-7 tokamak is introduced. DNB can provide a 6 A extracted current at 50 kV for 0.1 s in hydrogen. It can penetrate into the core plasma in HT-7. The CXRS system is designed to observe charge exchange （CX） transitions in the visible spectrum. CX light from the beam is focused onto 10 optical fibers, which view the plasma from -5 cm to 20 cm. The CXRS system can measure the ion temperature as low as 0.1 keV. With CXRS, the local ion temperature profile in HT-7 was obtained for the first time.展开更多
A new diagnostic based on Doppler shift is designed to measure the power profile of a hydrogen or deuterium neutral beam on the magnetic confined fusion machines. The interference filters and multi-channel photon dete...A new diagnostic based on Doppler shift is designed to measure the power profile of a hydrogen or deuterium neutral beam on the magnetic confined fusion machines. The interference filters and multi-channel photon detector array （PDA） are the main components of this diagnosis. The multi-channel PDA measures the line integrated Doppler Ha signal emitted by the neutral beam at one section in two directions. The local intensity of neutral beam can be obtained with the tomography technique. Compared to the conventional calorimeter diagnoses, this diagnosis can provide the beam profile without blocking the injection of neutral beam.展开更多
A new simple method is presented for the wavelength calibration and measurement of poloidal rotation velocities with X-ray imaging crystal spectrometer（XICS）in magnetic fusion devices.In this method,the toroidal rot...A new simple method is presented for the wavelength calibration and measurement of poloidal rotation velocities with X-ray imaging crystal spectrometer（XICS）in magnetic fusion devices.In this method,the toroidal rotation of plasma is applied for high precise alignment and wavelength calibration of the poloidal XICS.The measurement threshold of poloidal rotation velocity can be lowered to 1-3 km/s with this method.展开更多
Spectroscopy in the soft X-ray and extreme ultraviolet （XEUV） region is very im- portant in magnetic fusion research. Recently, two fiat-field spectrometers that utilize a varied line spacing grating to image the sp...Spectroscopy in the soft X-ray and extreme ultraviolet （XEUV） region is very im- portant in magnetic fusion research. Recently, two fiat-field spectrometers that utilize a varied line spacing grating to image the spectra of 1-13 nm and 5-50 nm were installed on EAST for core impurity emission monitoring and impurity transport study. The instruments were proven to be capable of observing spectral lines from low-Z impurities （Li, C, O, N, Ar, etc.） and highly ionized medium- and high-Z impurities （Fe, Cr, Ni, Cu, Mo, etc.）. For example, spectra in the wavelength intervals of 1-2 nm and 5-13 nm contained strong metal lines~ especially molybdenum lines during H-mode phases. Argon and nitrogen lines were also observed, which were injected for diagnostic purposes. Impurity lines were identified and compared to measurements on other magnetic fusion research devices. Detailed measurements of radial emission profiles from various impurity line emissions were also presented.展开更多
We observe the spectra of molybdenum for the first time since the first wall of our experimental advanced superconducting tokamak （EAST） was changed mainly to molybdenum tiles. A large amount of molybdenum accumulat...We observe the spectra of molybdenum for the first time since the first wall of our experimental advanced superconducting tokamak （EAST） was changed mainly to molybdenum tiles. A large amount of molybdenum accumulated in the central plasma where the long-lived m = 1 mode instability bursts is shown. Molybdenum is proved to be the main impurity species observed during the formation and lifetime of impurity-induced long-lived m= 1 mode. This may indicate that a close relationship exists between the high-Z impurity accumulation and the occurrence of long-lived m = 1 mode in EAST plasmas.展开更多
文摘电荷交换复合光谱(Charge e Xchange Recombination Spectroscopy,CXRS)诊断系统主要用于等离子体旋转速度和离子温度的测量。CXRS诊断的另外一个重要应用是通过测量光谱的绝对强度来确定杂质离子的密度,因此需要对系统进行绝对强度标定。在实验前通过精确校准过且各个波长强度已知的积分球光源对系统进行初步的标定;在实验过程中又利用托卡马克装置中等离子体自身产生的轫致辐射对系统的强度标定进行了进一步的检验。通过比较轫致辐射强度的实验测量值和理论计算值,可以发现两种方法得到的结果虽然存在一定的误差,但是它们的趋势是一致的。实验结果表明,利用轫致辐射进行绝对强度标定是可行的。
文摘A three-fluid equilibrium plasma with bulk plasma and energetic electrons has been observed on the Xuanlong-50(EXL-50) spherical torus, where the energetic electrons play a crucial role in sustaining the plasma current and pressure. In this study, the equilibrium of a multi-fluid plasma was investigated by analyzing the relationship between the external vertical magnetic field(B_(V)),plasma current(I_(p)), the poloidal ratio(β_(p)) and the Shafranov formula. Remarkably, our research demonstrates some validity of the Shafranov formula in the presence of multi-fluid plasma in EXL-50 spherical torus. This finding holds significant importance for future reactors as it allows for differentiation between alpha particles and background plasma. The study of multi-fluid plasma provides a significant reference value for the equilibrium reconstruction of burning plasma involving alpha particles.
基金supported by the Instruments R&D Project of the Chinese Academy of Sciences (title: Active Beam Spectra Diagnostic)partially supported by National Natural Science Foundation of China (Nos. 10725523, 10975155)the U. S. Department of Energy Under Grant No. DE-FG02-03ER54729 to the University of Texas
文摘Charge exchange recombination spectroscopy （CXRS） based on a diagnostic neutral beam （DNB） installed in the HT-7 tokamak is introduced. DNB can provide a 6 A extracted current at 50 kV for 0.1 s in hydrogen. It can penetrate into the core plasma in HT-7. The CXRS system is designed to observe charge exchange （CX） transitions in the visible spectrum. CX light from the beam is focused onto 10 optical fibers, which view the plasma from -5 cm to 20 cm. The CXRS system can measure the ion temperature as low as 0.1 keV. With CXRS, the local ion temperature profile in HT-7 was obtained for the first time.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10475078, and the JSPS-CAS Core-University Programme on Plasma and Nuclear Fusion in 2006.
文摘A new diagnostic based on Doppler shift is designed to measure the power profile of a hydrogen or deuterium neutral beam on the magnetic confined fusion machines. The interference filters and multi-channel photon detector array （PDA） are the main components of this diagnosis. The multi-channel PDA measures the line integrated Doppler Ha signal emitted by the neutral beam at one section in two directions. The local intensity of neutral beam can be obtained with the tomography technique. Compared to the conventional calorimeter diagnoses, this diagnosis can provide the beam profile without blocking the injection of neutral beam.
基金supported by National Natural Science Foundation of China(Nos.11175208,11305212 and 11405212)the National Magnetic Confinement Fusion Science Program of China(No.2013GB112004)JSPS-NRF-NSFC A3 Foresight Program in the Field of Plasma Physics(No.11261140328)
文摘A new simple method is presented for the wavelength calibration and measurement of poloidal rotation velocities with X-ray imaging crystal spectrometer（XICS）in magnetic fusion devices.In this method,the toroidal rotation of plasma is applied for high precise alignment and wavelength calibration of the poloidal XICS.The measurement threshold of poloidal rotation velocity can be lowered to 1-3 km/s with this method.
基金supported by National Natural Science Foundation of China(Nos.11175208,11275231 and 11305207)the National Magnetic Confinement Fusion Science Program of China(Nos.2012GB101001 and 2013GB112004)+1 种基金Scientific Instrument Development Project of Chinese Academy of Sciences(No.YZ200922)JSPS-NRF-NSFC A3 Foresight Program in the Field of Plasma Physics(No.11261140328)
文摘Spectroscopy in the soft X-ray and extreme ultraviolet （XEUV） region is very im- portant in magnetic fusion research. Recently, two fiat-field spectrometers that utilize a varied line spacing grating to image the spectra of 1-13 nm and 5-50 nm were installed on EAST for core impurity emission monitoring and impurity transport study. The instruments were proven to be capable of observing spectral lines from low-Z impurities （Li, C, O, N, Ar, etc.） and highly ionized medium- and high-Z impurities （Fe, Cr, Ni, Cu, Mo, etc.）. For example, spectra in the wavelength intervals of 1-2 nm and 5-13 nm contained strong metal lines~ especially molybdenum lines during H-mode phases. Argon and nitrogen lines were also observed, which were injected for diagnostic purposes. Impurity lines were identified and compared to measurements on other magnetic fusion research devices. Detailed measurements of radial emission profiles from various impurity line emissions were also presented.
基金Supported by the National Magnetic Confinement Fusion Science Program of China under Grant Nos 2013GB112004 and 2015GB103002the Natural Science Research Key Project of Education Department of Anhui Province under Grant No KJ2016A434+3 种基金the Doctoral Scientific Research Foundation of Anqing Normal University under Grant No 044-140001000024the National Natural Science Foundation of China under Grant Nos 11275231,11305212,11405212 and 11261140328the Innovative Program of Development Foundation of Hefei Center for Physical Science and Technology under Grant No 2014FXCX003the Hefei Science Center CAS Users with Potential Project under Grant No 2015HSC-UP007
文摘We observe the spectra of molybdenum for the first time since the first wall of our experimental advanced superconducting tokamak （EAST） was changed mainly to molybdenum tiles. A large amount of molybdenum accumulated in the central plasma where the long-lived m = 1 mode instability bursts is shown. Molybdenum is proved to be the main impurity species observed during the formation and lifetime of impurity-induced long-lived m= 1 mode. This may indicate that a close relationship exists between the high-Z impurity accumulation and the occurrence of long-lived m = 1 mode in EAST plasmas.
