Purpose To protect accelerator devices from being damaged by high-power beam,a new beam dump system is under design for HIAF-BRing.Method Based on the optical characteristics,unwanted particles are safely deflected to ...Purpose To protect accelerator devices from being damaged by high-power beam,a new beam dump system is under design for HIAF-BRing.Method Based on the optical characteristics,unwanted particles are safely deflected to a specific internal absorber through a local bump orbit generated by active-discharging magnets,which is achieved by paralleling a bleeder resistor of 600 m�to two of dipole magnet power supplies.Results Taking alignment and multipolefield errors into account,discarded beam can be dumped within 5 ms with an efficiency of more than 99.8%at any operation stage.Conclusion The proposed beam dump solution satisfies the machine protection requirements for BRing and can provide a new idea for similar facilities.展开更多
Purpose The machine protection system(MPS)is an essential part of the BRing(Booster Ring)at the HIAF(High Intensity heavy ion Accelerator Facility)to protect the accelerator from possible accidents.The high accumulati...Purpose The machine protection system(MPS)is an essential part of the BRing(Booster Ring)at the HIAF(High Intensity heavy ion Accelerator Facility)to protect the accelerator from possible accidents.The high accumulation intensity and the complex operation mode of the BRing require MPS to respond quickly and operate stably.So,the detailed physical scheme of beam dump is proposed,and the corresponding simulation results are discussed in this paper.Method For this purpose,a multi-phased beam dump scheme based on the bipolar operation of fast extraction kicker magnets is proposed.The basic physical dimensions of the stoppers and energy deposited analysis have been calculated.Results and conclusion The multi-phased beam dump scheme is able to meet the engineering requirements,and the stopping efficiency can reach 100%for bunched beam.展开更多
A two-dimensional electromagnetic particle-in-cell simulation model is proposed to study the density evolution and collective stopping of electron beams in background plasmas.We show here the formation of the multi-la...A two-dimensional electromagnetic particle-in-cell simulation model is proposed to study the density evolution and collective stopping of electron beams in background plasmas.We show here the formation of the multi-layer structure of the relativistic electron beam in the plasma due to the different betatron frequency from the beam front to the beam tail.Meanwhile,the nonuniformity of the longitudinal wakefield is the essential reason for the multi-layer structure formation in beam phase space.The influences of beam parameters(beam radius and transverse density profile)on the formation of the multi-layer structure and collective stopping in background plasmas are also considered.展开更多
束流垃圾桶的材料、结构、尺寸的正确设计对于确保高能环形对撞机(Circular Electron Positron Collider,CEPC)直线加速器的安全运行有重要意义。采用蒙特卡罗程序FLUKA,研究了概念设计阶段的CEPC直线加速器束流垃圾桶的初步设计方案,...束流垃圾桶的材料、结构、尺寸的正确设计对于确保高能环形对撞机(Circular Electron Positron Collider,CEPC)直线加速器的安全运行有重要意义。采用蒙特卡罗程序FLUKA,研究了概念设计阶段的CEPC直线加速器束流垃圾桶的初步设计方案,给出了作为吸收体设计依据的射程的不同计算方法及验证过程,以及屏蔽体部分的材料选择与总体屏蔽厚度的关系;计算过程中引入减方差技巧提高了计算结果的精确程度。展开更多
基金support from The National Key R&D Program of China(Grant No.2019YFA0405400)China National Funds for Distinguished Young Scientists(No.11825505)Guangdong Innovative and Entrepreneurial Research Team Program(Grant No.2016ZT06G373).
文摘Purpose To protect accelerator devices from being damaged by high-power beam,a new beam dump system is under design for HIAF-BRing.Method Based on the optical characteristics,unwanted particles are safely deflected to a specific internal absorber through a local bump orbit generated by active-discharging magnets,which is achieved by paralleling a bleeder resistor of 600 m�to two of dipole magnet power supplies.Results Taking alignment and multipolefield errors into account,discarded beam can be dumped within 5 ms with an efficiency of more than 99.8%at any operation stage.Conclusion The proposed beam dump solution satisfies the machine protection requirements for BRing and can provide a new idea for similar facilities.
基金Thanks for the support from the National Key R&D Program of China(Grant NO.2019YFA0405400)National Natural Science Foundation of China(Grant No.11905268)the support from Guangdong Innovative and Entrepreneurial Research Team Program(Grant No.2016ZT06G373).
文摘Purpose The machine protection system(MPS)is an essential part of the BRing(Booster Ring)at the HIAF(High Intensity heavy ion Accelerator Facility)to protect the accelerator from possible accidents.The high accumulation intensity and the complex operation mode of the BRing require MPS to respond quickly and operate stably.So,the detailed physical scheme of beam dump is proposed,and the corresponding simulation results are discussed in this paper.Method For this purpose,a multi-phased beam dump scheme based on the bipolar operation of fast extraction kicker magnets is proposed.The basic physical dimensions of the stoppers and energy deposited analysis have been calculated.Results and conclusion The multi-phased beam dump scheme is able to meet the engineering requirements,and the stopping efficiency can reach 100%for bunched beam.
基金supported by National Natural Science Foundation of China(Nos.12075046 and 11775042)。
文摘A two-dimensional electromagnetic particle-in-cell simulation model is proposed to study the density evolution and collective stopping of electron beams in background plasmas.We show here the formation of the multi-layer structure of the relativistic electron beam in the plasma due to the different betatron frequency from the beam front to the beam tail.Meanwhile,the nonuniformity of the longitudinal wakefield is the essential reason for the multi-layer structure formation in beam phase space.The influences of beam parameters(beam radius and transverse density profile)on the formation of the multi-layer structure and collective stopping in background plasmas are also considered.
文摘束流垃圾桶的材料、结构、尺寸的正确设计对于确保高能环形对撞机(Circular Electron Positron Collider,CEPC)直线加速器的安全运行有重要意义。采用蒙特卡罗程序FLUKA,研究了概念设计阶段的CEPC直线加速器束流垃圾桶的初步设计方案,给出了作为吸收体设计依据的射程的不同计算方法及验证过程,以及屏蔽体部分的材料选择与总体屏蔽厚度的关系;计算过程中引入减方差技巧提高了计算结果的精确程度。