The electron cooler was installed in one of the straight sections of CSRe which is used to provide high-qualitybeams for experiments. Longitudinally the dynamics of the cooling process have been studied for a series o...The electron cooler was installed in one of the straight sections of CSRe which is used to provide high-qualitybeams for experiments. Longitudinally the dynamics of the cooling process have been studied for a series of electronbeam parameters and the friction force was measured with the aid of an RF-buncher for C6+ (122 MeV/u) and O8+(122 MeV/u) ions. The cooling time at different electron beam state have been measured, too.展开更多
The electron cooler at the experimental Cooler Storage Ring(CSRe)has been upgraded with an embedded electron energy fast detuning system for the merged-beams electron-ion collision experiments.A plastic scintillation ...The electron cooler at the experimental Cooler Storage Ring(CSRe)has been upgraded with an embedded electron energy fast detuning system for the merged-beams electron-ion collision experiments.A plastic scintillation detector(PSD)and a multi-wire proportional chamber(MWPC)detector have been developed and installed downstream of the electron cooler to detect the ionized ions in the electron-ion collision experiments at the CSRe.展开更多
Recombination of Ar^(14+),Ar^(15+),Ca^(16+) and Ni^(19+) ions with electrons has been investigated at low energy range at the CSRm.For each ion,the absolute recombination rate coefficients have been measured with elec...Recombination of Ar^(14+),Ar^(15+),Ca^(16+) and Ni^(19+) ions with electrons has been investigated at low energy range at the CSRm.For each ion,the absolute recombination rate coefficients have been measured with electron-ion collision energies from 0 to 1000 meV which include the radiative recombination(RR)and also dielectronic recombination(DR)processes.In order to interpret the measured results.展开更多
The absolute rate cofficients for dielectronic recombination(DR)of F-like Ni^(19+) ions were measured by employing the electron-ion merged-beam technique at the heavy-ion storage ring CSRm.The measured DR spectrum cov...The absolute rate cofficients for dielectronic recombination(DR)of F-like Ni^(19+) ions were measured by employing the electron-ion merged-beam technique at the heavy-ion storage ring CSRm.The measured DR spectrum covers the energy range of 0~70 eV.展开更多
The absolute rate coefficients for dielectronic recombination(DR)of Na-like Kr^(25+) ions were measured by employing the electron-ion merged-beam technique at the heavy-ion storage ring CSRm.The measured DR spectrum c...The absolute rate coefficients for dielectronic recombination(DR)of Na-like Kr^(25+) ions were measured by employing the electron-ion merged-beam technique at the heavy-ion storage ring CSRm.The measured DR spectrum covers the energy range of 0~70 eV.展开更多
Laser cooling is one of the most promising techniques to achieve high phase-space densities or even crystalline beams for relativistic heavy ion beams at storage rings[1].Based on the success of laser cooling of C^(3+...Laser cooling is one of the most promising techniques to achieve high phase-space densities or even crystalline beams for relativistic heavy ion beams at storage rings[1].Based on the success of laser cooling of C^(3+) at the ESR[2,3],and the experience of test laser cooling experiments at the CSRe[4],laser cooling of lithium-like O^(5+) ion beams with an relativistic energy of 275.7 MeV/u was achieved for the first time at the heavy-ion storage ring CSRe in Lanzhou,China.In the experiment,a CW laser system with a wavelength of 220 nm was used to match the optical transition of 2s1=2-2p1=2 of O^(5+)ions.In order to cool the relativistic ion beams with only one counterpropagating CW laser,the ion beams were bunched by applying a sinusoidal voltage to the RF-buncher system.Fig.展开更多
Based on the successful dielectronic recombination(DR)experiments with intermediate charge state ions of Belike Ar^(14+[1]) and Ca^(16+[2]) at the CSRm,we are preparing the precision spectroscopy of DR experiments wit...Based on the successful dielectronic recombination(DR)experiments with intermediate charge state ions of Belike Ar^(14+[1]) and Ca^(16+[2]) at the CSRm,we are preparing the precision spectroscopy of DR experiments with highly charged ions and even radioactive ions at the CSRe.A test electron-ion recombination experiment of Boron-like Ar13+ions was performed with a section of the new electron beam energy detuning system,which will be installed at the CSRe.Fig.1 presents the measured and also the calculated DR spectra for B-like Ar^(13+) from 0 to 3 eV.The experimental result indicates that the new detuning system is more stable and has a higher energy resolution than the previous detuning system used at the CSRm.It paves the way for the upcoming DR experiments with highly charged heavy ions at the CSRe.In addition,the flexible atomic code(FAC)was employed to calculate the DR resonance strengths of Boron-like Ar^(13+) to compare with the experimental result.展开更多
配备电子冷却装置的重离子储存环为开展高电荷态离子的双电子复合(dielectronic recombination,DR)精密谱学研究提供了绝佳的实验平台。本工作在兰州重离子加速器冷却储存环主环(HIRFL-CSRm)上开展了类锂36,40Ar15+离子的双电子复合实验...配备电子冷却装置的重离子储存环为开展高电荷态离子的双电子复合(dielectronic recombination,DR)精密谱学研究提供了绝佳的实验平台。本工作在兰州重离子加速器冷却储存环主环(HIRFL-CSRm)上开展了类锂36,40Ar15+离子的双电子复合实验,实验观测了电子-离子质心系能量范围为0～35 e V的双电子复合速率系数谱。通过外推法获得了^(36,40)Ar^(15+)离子2s_(1/2)→2p_(1/2)和2s_(1/2)→2p_(3/2)的跃迁能量。同时利用GRASP2K程序理论计算了^(36,40)Ar^(15+)离子2s_(1/2)→2p_(1/2)和2s_(1/2)→2p_(3/2)跃迁的质量移动因子和场移动因子,进而得到双电子复合谱的同位素移动值。^(36,40)Ar^(15+)离子2s_(1/2)→2p_(1/2)和2s_(1/2)→2p_(3/2)同位素移动分别为0.861 me V和0.868 me V。它们均小于目前CSRm上双电子复合实验的实验分辨为～10 me V,进而解释了实验测量的DR谱上未能观察到同位素移动的原因。然而,高电荷态离子的同位素移动场效应与原子序数Z^5成正比,因此,在重离子加速器冷却储存环实验环(HIRFL-CSRe)以及未来大型加速器——强流重离子加速器装置(HIAF)上有望通过DR精密谱学方法研究高电荷态重离子甚至放射性离子的同位素移动,进而获得相关原子核的核电荷半径等信息。展开更多
文摘The electron cooler was installed in one of the straight sections of CSRe which is used to provide high-qualitybeams for experiments. Longitudinally the dynamics of the cooling process have been studied for a series of electronbeam parameters and the friction force was measured with the aid of an RF-buncher for C6+ (122 MeV/u) and O8+(122 MeV/u) ions. The cooling time at different electron beam state have been measured, too.
基金National Key R&D Program of China(2017YFA0402300)National Natural Science Foundation of China(U1932207,11904371)。
文摘The electron cooler at the experimental Cooler Storage Ring(CSRe)has been upgraded with an embedded electron energy fast detuning system for the merged-beams electron-ion collision experiments.A plastic scintillation detector(PSD)and a multi-wire proportional chamber(MWPC)detector have been developed and installed downstream of the electron cooler to detect the ionized ions in the electron-ion collision experiments at the CSRe.
基金National Key R&D Program of China(2017YFA0402300)National Natural Science Foundation of China(U1932207,11904371,U1732133)。
文摘Recombination of Ar^(14+),Ar^(15+),Ca^(16+) and Ni^(19+) ions with electrons has been investigated at low energy range at the CSRm.For each ion,the absolute recombination rate coefficients have been measured with electron-ion collision energies from 0 to 1000 meV which include the radiative recombination(RR)and also dielectronic recombination(DR)processes.In order to interpret the measured results.
基金National Key R&D Program of China(2017YFA0402300)National Natural Science Foundation of China(U1732133,Y602080YQ0,Y602110XD0)。
文摘The absolute rate cofficients for dielectronic recombination(DR)of F-like Ni^(19+) ions were measured by employing the electron-ion merged-beam technique at the heavy-ion storage ring CSRm.The measured DR spectrum covers the energy range of 0~70 eV.
基金National Key R&D Program of China(2017YFA0402300)National Natural Science Foundation of China(U1732133,Y602080YQ0,Y602110XD0)。
文摘The absolute rate coefficients for dielectronic recombination(DR)of Na-like Kr^(25+) ions were measured by employing the electron-ion merged-beam technique at the heavy-ion storage ring CSRm.The measured DR spectrum covers the energy range of 0~70 eV.
基金National Natural Science Foundation(11221064)of China,External Cooperation Program of CAS(GJHZ1305)National Postdoctoral Program for Innovative Talents(BX201700256)。
文摘Laser cooling is one of the most promising techniques to achieve high phase-space densities or even crystalline beams for relativistic heavy ion beams at storage rings[1].Based on the success of laser cooling of C^(3+) at the ESR[2,3],and the experience of test laser cooling experiments at the CSRe[4],laser cooling of lithium-like O^(5+) ion beams with an relativistic energy of 275.7 MeV/u was achieved for the first time at the heavy-ion storage ring CSRe in Lanzhou,China.In the experiment,a CW laser system with a wavelength of 220 nm was used to match the optical transition of 2s1=2-2p1=2 of O^(5+)ions.In order to cool the relativistic ion beams with only one counterpropagating CW laser,the ion beams were bunched by applying a sinusoidal voltage to the RF-buncher system.Fig.
基金National Key R&D Program of China(2017YFA0402300)National Natural Science Foundation(11320101003,U1732133)。
文摘Based on the successful dielectronic recombination(DR)experiments with intermediate charge state ions of Belike Ar^(14+[1]) and Ca^(16+[2]) at the CSRm,we are preparing the precision spectroscopy of DR experiments with highly charged ions and even radioactive ions at the CSRe.A test electron-ion recombination experiment of Boron-like Ar13+ions was performed with a section of the new electron beam energy detuning system,which will be installed at the CSRe.Fig.1 presents the measured and also the calculated DR spectra for B-like Ar^(13+) from 0 to 3 eV.The experimental result indicates that the new detuning system is more stable and has a higher energy resolution than the previous detuning system used at the CSRm.It paves the way for the upcoming DR experiments with highly charged heavy ions at the CSRe.In addition,the flexible atomic code(FAC)was employed to calculate the DR resonance strengths of Boron-like Ar^(13+) to compare with the experimental result.
文摘配备电子冷却装置的重离子储存环为开展高电荷态离子的双电子复合(dielectronic recombination,DR)精密谱学研究提供了绝佳的实验平台。本工作在兰州重离子加速器冷却储存环主环(HIRFL-CSRm)上开展了类锂36,40Ar15+离子的双电子复合实验,实验观测了电子-离子质心系能量范围为0～35 e V的双电子复合速率系数谱。通过外推法获得了^(36,40)Ar^(15+)离子2s_(1/2)→2p_(1/2)和2s_(1/2)→2p_(3/2)的跃迁能量。同时利用GRASP2K程序理论计算了^(36,40)Ar^(15+)离子2s_(1/2)→2p_(1/2)和2s_(1/2)→2p_(3/2)跃迁的质量移动因子和场移动因子,进而得到双电子复合谱的同位素移动值。^(36,40)Ar^(15+)离子2s_(1/2)→2p_(1/2)和2s_(1/2)→2p_(3/2)同位素移动分别为0.861 me V和0.868 me V。它们均小于目前CSRm上双电子复合实验的实验分辨为～10 me V,进而解释了实验测量的DR谱上未能观察到同位素移动的原因。然而,高电荷态离子的同位素移动场效应与原子序数Z^5成正比,因此,在重离子加速器冷却储存环实验环(HIRFL-CSRe)以及未来大型加速器——强流重离子加速器装置(HIAF)上有望通过DR精密谱学方法研究高电荷态重离子甚至放射性离子的同位素移动,进而获得相关原子核的核电荷半径等信息。
