空间推进所用的电子回旋共振离子源(ECRIS)应具有体积小、效率高的特点.本文研究的ECRIS使用永磁体环产生磁场,有效减小了体积,该离子源利用微波在磁场中加热电子,电子与中性气体发生电离碰撞产生等离子体.磁场在微波加热电子的过程中...空间推进所用的电子回旋共振离子源(ECRIS)应具有体积小、效率高的特点.本文研究的ECRIS使用永磁体环产生磁场,有效减小了体积,该离子源利用微波在磁场中加热电子,电子与中性气体发生电离碰撞产生等离子体.磁场在微波加热电子的过程中起关键作用,同时影响离子源内等离子体的约束和输运.通过比较四种磁路结构离子源的离子电流引出特性来研究磁场对10 cm ECRIS性能的影响.实验发现:在使用氩气的条件下,特定结构的离子源可引出160 mA的离子电流,最高推进剂利用率达60%,最小放电损耗为120 W·A^(-1);所有离子源均存在多个工作状态,工作状态在微波功率、气体流量、引出电压变化时会发生突变.离子源发生状态突变时的微波功率、气体流量的大小与离子源内磁体的位置有关.通过比较不同离子源的引出离子束流、放电损耗、气体利用率、工作稳定性的差异,归纳了磁场结构对此种ECRIS引出特性的影响规律,分析了其中的机理.实验结果表明:保持输入微波功率、气体流量、引出电压不变时,增大共振区的范围、减小共振区到栅极的距离,离子源能引出更大的离子电流;减小共振区到微波功率入口、气体入口的距离能降低维持离子源高状态所需的最小微波功率和最小气体流量,提高气体利用率,但会导致放电损耗增大.研究结果有助于深化对此类离子源工作过程的认识,为其设计和性能优化提供参考.展开更多
研制了一台体积和重量都较大、设计性能较高的全永磁电子回旋共振(Electron cyclotron resonance, ECR)离子源LAPECR2(Lanzhou all permanent magnetic ECR ion source No.2)。该离子源将用于中国科学院近代物理研究所320 kV高压平台,...研制了一台体积和重量都较大、设计性能较高的全永磁电子回旋共振(Electron cyclotron resonance, ECR)离子源LAPECR2(Lanzhou all permanent magnetic ECR ion source No.2)。该离子源将用于中国科学院近代物理研究所320 kV高压平台,为其提供强流高电荷态离子束流。LAPECR2的研制采用全新的全永磁磁体结构设计,通过采用高性能的NdFeB永磁材料、优化的磁结构设计以及精确的计算,实测源体的磁场参数能达到高性能ECR离子源的设计要求。离子源采用较高频率的14.5 GHz微波馈入加热等离子体,波导直接馈入离子源以增强馈入微波的稳定性与效率。此外,还大量采用了一些有利于提高离子源高电荷态离子产额的关键技术,如铝内衬等离子体弧腔、负偏压盘、铝制等离子体电极、三电极引出系统、辅助掺气等。展开更多
High current hydrogen molecular ion beam is obtained with a specially designed stainless steel liner permanent magnet2.45-GHz electron–cyclotron resonance(ECR) ion source(PMECR II) at Peking University(PKU). To furth...High current hydrogen molecular ion beam is obtained with a specially designed stainless steel liner permanent magnet2.45-GHz electron–cyclotron resonance(ECR) ion source(PMECR II) at Peking University(PKU). To further understand the physics of the hydrogen generation process inside a plasma chamber, theoretical and experimental investigations on the liner material of the plasma chamber in different running conditions are carried out. Several kinds of materials, stainless steel(SS), tantalum(Ta), quartz, and aluminum(Al) are selected in our study. Experimental results show that stainless steel and tantalum are much better than others in H^+_2 generation. During the experiment, an increasing trend in H^+_2 fraction is observed with stainless steel liner after O_2 discharge inside the ion source. Surface analyses show that the roughness change on the surface after O_2 discharge may be responsible for this phenomenon. After these studies, the pure current of H^+_2 ions can reach 42.3 mA with a fraction of 52.9%. More details are presented in this paper.展开更多
To improve the accuracy and usability of the superconducting electron cyclotron resonance ion source with advanced design in Lanzhou(SECRAL), an upgraded version of the control system was designed and tested. This pap...To improve the accuracy and usability of the superconducting electron cyclotron resonance ion source with advanced design in Lanzhou(SECRAL), an upgraded version of the control system was designed and tested. This paper details the architecture of the optimized control system and presents the results of its use in the long-term operation of the accelerator. The control system software, based on Visual C++, was developed following the model-view-controller architecture design pattern. The data acquisition system was based on a field-programmable gate array integrated circuit. In addition, control strategies were optimized for higher operational stability. The upgraded control system was tested with a U^(33+) ion beam at SECRAL, where it provided a data acquisition time of less than 1 ms. The fast reaction time and highprecision data processing during beam tuning verified the stability and maintainability of the control system.展开更多
Since fullerene (C60) was discovered, it is a hot topic to study various collision processes between atomic ion, electron, photon, and fullerene collisions. We established an experimental setup for highly charged ion-...Since fullerene (C60) was discovered, it is a hot topic to study various collision processes between atomic ion, electron, photon, and fullerene collisions. We established an experimental setup for highly charged ion-C60 collisions at the ECR ion source beam-line in IMP. The ions extracted from ECR ion source are展开更多
LECR3 (Lanzhou ECR ion source No.3) is a high performance Electron Cyclotron Resonance ion source designed for atomic physics research. It was designed and fabricated in 2000, and after about one year's commission...LECR3 (Lanzhou ECR ion source No.3) is a high performance Electron Cyclotron Resonance ion source designed for atomic physics research. It was designed and fabricated in 2000, and after about one year's commissioning, it was used to deliver multiply charged ion beams for the successive atomic physics experimental terminals. This source is a double-frequency heating ion source. It was designed running at 10 GHz or 14.展开更多
The interactions between highly charged ions and materials (atoms, molecules, clusters, surfaces, and bio-molecules, etc) have great importance not only for fundamental interests but also for applied researches. For l...The interactions between highly charged ions and materials (atoms, molecules, clusters, surfaces, and bio-molecules, etc) have great importance not only for fundamental interests but also for applied researches. For low-energy collisions, the highly charged projectiles are usually provided by ECR ion sources or EBIT/S. The projectile energy is around 30q keV (where q is the projectile charge) and.below, while for energies up to展开更多
LECR2 (Lanzhou Electron Cyclotron Resonance ion source No.2), which was built in 1997, has been running for more than 30 000 h and provided more than one hundred kinds of ion beams for HIRFL. This ion source was consi...LECR2 (Lanzhou Electron Cyclotron Resonance ion source No.2), which was built in 1997, has been running for more than 30 000 h and provided more than one hundred kinds of ion beams for HIRFL. This ion source was considered to be one of the best ECRISs in the world when it was under commissioning because of its展开更多
文摘空间推进所用的电子回旋共振离子源(ECRIS)应具有体积小、效率高的特点.本文研究的ECRIS使用永磁体环产生磁场,有效减小了体积,该离子源利用微波在磁场中加热电子,电子与中性气体发生电离碰撞产生等离子体.磁场在微波加热电子的过程中起关键作用,同时影响离子源内等离子体的约束和输运.通过比较四种磁路结构离子源的离子电流引出特性来研究磁场对10 cm ECRIS性能的影响.实验发现:在使用氩气的条件下,特定结构的离子源可引出160 mA的离子电流,最高推进剂利用率达60%,最小放电损耗为120 W·A^(-1);所有离子源均存在多个工作状态,工作状态在微波功率、气体流量、引出电压变化时会发生突变.离子源发生状态突变时的微波功率、气体流量的大小与离子源内磁体的位置有关.通过比较不同离子源的引出离子束流、放电损耗、气体利用率、工作稳定性的差异,归纳了磁场结构对此种ECRIS引出特性的影响规律,分析了其中的机理.实验结果表明:保持输入微波功率、气体流量、引出电压不变时,增大共振区的范围、减小共振区到栅极的距离,离子源能引出更大的离子电流;减小共振区到微波功率入口、气体入口的距离能降低维持离子源高状态所需的最小微波功率和最小气体流量,提高气体利用率,但会导致放电损耗增大.研究结果有助于深化对此类离子源工作过程的认识,为其设计和性能优化提供参考.
文摘研制了一台体积和重量都较大、设计性能较高的全永磁电子回旋共振(Electron cyclotron resonance, ECR)离子源LAPECR2(Lanzhou all permanent magnetic ECR ion source No.2)。该离子源将用于中国科学院近代物理研究所320 kV高压平台,为其提供强流高电荷态离子束流。LAPECR2的研制采用全新的全永磁磁体结构设计,通过采用高性能的NdFeB永磁材料、优化的磁结构设计以及精确的计算,实测源体的磁场参数能达到高性能ECR离子源的设计要求。离子源采用较高频率的14.5 GHz微波馈入加热等离子体,波导直接馈入离子源以增强馈入微波的稳定性与效率。此外,还大量采用了一些有利于提高离子源高电荷态离子产额的关键技术,如铝内衬等离子体弧腔、负偏压盘、铝制等离子体电极、三电极引出系统、辅助掺气等。
基金supported by the National Natural Science Foundation of China(Grant Nos.11175009 and 11575013)
文摘High current hydrogen molecular ion beam is obtained with a specially designed stainless steel liner permanent magnet2.45-GHz electron–cyclotron resonance(ECR) ion source(PMECR II) at Peking University(PKU). To further understand the physics of the hydrogen generation process inside a plasma chamber, theoretical and experimental investigations on the liner material of the plasma chamber in different running conditions are carried out. Several kinds of materials, stainless steel(SS), tantalum(Ta), quartz, and aluminum(Al) are selected in our study. Experimental results show that stainless steel and tantalum are much better than others in H^+_2 generation. During the experiment, an increasing trend in H^+_2 fraction is observed with stainless steel liner after O_2 discharge inside the ion source. Surface analyses show that the roughness change on the surface after O_2 discharge may be responsible for this phenomenon. After these studies, the pure current of H^+_2 ions can reach 42.3 mA with a fraction of 52.9%. More details are presented in this paper.
基金supported by the National Natural Science Foundation of China(No.u1232123)
文摘To improve the accuracy and usability of the superconducting electron cyclotron resonance ion source with advanced design in Lanzhou(SECRAL), an upgraded version of the control system was designed and tested. This paper details the architecture of the optimized control system and presents the results of its use in the long-term operation of the accelerator. The control system software, based on Visual C++, was developed following the model-view-controller architecture design pattern. The data acquisition system was based on a field-programmable gate array integrated circuit. In addition, control strategies were optimized for higher operational stability. The upgraded control system was tested with a U^(33+) ion beam at SECRAL, where it provided a data acquisition time of less than 1 ms. The fast reaction time and highprecision data processing during beam tuning verified the stability and maintainability of the control system.
文摘Since fullerene (C60) was discovered, it is a hot topic to study various collision processes between atomic ion, electron, photon, and fullerene collisions. We established an experimental setup for highly charged ion-C60 collisions at the ECR ion source beam-line in IMP. The ions extracted from ECR ion source are
文摘LECR3 (Lanzhou ECR ion source No.3) is a high performance Electron Cyclotron Resonance ion source designed for atomic physics research. It was designed and fabricated in 2000, and after about one year's commissioning, it was used to deliver multiply charged ion beams for the successive atomic physics experimental terminals. This source is a double-frequency heating ion source. It was designed running at 10 GHz or 14.
文摘The interactions between highly charged ions and materials (atoms, molecules, clusters, surfaces, and bio-molecules, etc) have great importance not only for fundamental interests but also for applied researches. For low-energy collisions, the highly charged projectiles are usually provided by ECR ion sources or EBIT/S. The projectile energy is around 30q keV (where q is the projectile charge) and.below, while for energies up to
文摘LECR2 (Lanzhou Electron Cyclotron Resonance ion source No.2), which was built in 1997, has been running for more than 30 000 h and provided more than one hundred kinds of ion beams for HIRFL. This ion source was considered to be one of the best ECRISs in the world when it was under commissioning because of its