粒子云网格(Particle In cell,PIC)方法是研究带电粒子在加速器中运动的关键工具之一。基于PIC算法,开发了模拟强流条件下的束流动力学模拟程序TOPOPIC(Trace of Particle Orbit with PIC method),并且利用TOPOPIC,研究了束流在四极铁...粒子云网格(Particle In cell,PIC)方法是研究带电粒子在加速器中运动的关键工具之一。基于PIC算法,开发了模拟强流条件下的束流动力学模拟程序TOPOPIC(Trace of Particle Orbit with PIC method),并且利用TOPOPIC,研究了束流在四极铁周期结构(FODO)中的传输问题。结果表明,在强流条件下空间电荷效应显著地影响了束流的整体行为和单粒子的运动轨迹。最后比较了TOPOPIC程序和通用的BEAMPATH程序在相同条件下的计算结果,可以看到两个程序给出的模拟结果吻合得非常好,这表明TOPOPIC程序的计算结果是合理、可靠的。展开更多
We report on a new design for an ILC 3.2 km damping ring,with 2 arcs based on the FODO cell and 2 straight sections that are nearly the same as the newest version of the 6.4 km ring DCO4.This new lattice requires fewe...We report on a new design for an ILC 3.2 km damping ring,with 2 arcs based on the FODO cell and 2 straight sections that are nearly the same as the newest version of the 6.4 km ring DCO4.This new lattice requires fewer magnets and a lower RF voltage, and has a better dynamic aperture than DCO4 while maintaining flexibility in regard to the momentum compaction factor.So far, this design is the only one satisfying all the requirements for a 3.2 km ring.The work on the lattice design and the dynamic aperture study is presented in detail.展开更多
An experimental muon source is planned for the China Spallation Neutron Source.A simplified beamline with a limited number of magnets is achieved using a FODO lattice for implementation in a future preliminary stage.T...An experimental muon source is planned for the China Spallation Neutron Source.A simplified beamline with a limited number of magnets is achieved using a FODO lattice for implementation in a future preliminary stage.The yield of the muon delivered to the experimental sample is slightly larger than 10^5 μ^+/s within the FWHM beam spot(-φ30 mm)from a thick muon target.In addition,the beam polarization is 92%and the contamination that is mainly formed by positrons is approximately a fraction of 1%.展开更多
The International Linear Collider （ILC）, which is based on super-conducting RF acceleration technology, requires the damping rings to provide beams with extremely small equilibrium emittance, and large acceptance to...The International Linear Collider （ILC）, which is based on super-conducting RF acceleration technology, requires the damping rings to provide beams with extremely small equilibrium emittance, and large acceptance to ensure good injection efficiency for high-emittance, and high-energy spread beam from the positron source. In order to reduce the cost for ILC damping rings, an alternative lattice which is different from the baseline configuration design has been designed with modified FODO arc cells, and the total quadrupole number has been reduced by half. At the same time, to decrease the total cost involved in constructing access shafts needed to supply power, cryogenics etc. for the wigglers and other systems, the number of wiggler sections is decreased from 8 to 4, and further to 2. This new lattice has been optimized to have a good dynamic aperture. This alternative ILC damping ring lattice design will reduce the cost largely as compared with the baseline design.展开更多
文摘粒子云网格(Particle In cell,PIC)方法是研究带电粒子在加速器中运动的关键工具之一。基于PIC算法,开发了模拟强流条件下的束流动力学模拟程序TOPOPIC(Trace of Particle Orbit with PIC method),并且利用TOPOPIC,研究了束流在四极铁周期结构(FODO)中的传输问题。结果表明,在强流条件下空间电荷效应显著地影响了束流的整体行为和单粒子的运动轨迹。最后比较了TOPOPIC程序和通用的BEAMPATH程序在相同条件下的计算结果,可以看到两个程序给出的模拟结果吻合得非常好,这表明TOPOPIC程序的计算结果是合理、可靠的。
基金supported by the National Natural Science Foundation of China (10525525 and 10775154)
文摘We report on a new design for an ILC 3.2 km damping ring,with 2 arcs based on the FODO cell and 2 straight sections that are nearly the same as the newest version of the 6.4 km ring DCO4.This new lattice requires fewer magnets and a lower RF voltage, and has a better dynamic aperture than DCO4 while maintaining flexibility in regard to the momentum compaction factor.So far, this design is the only one satisfying all the requirements for a 3.2 km ring.The work on the lattice design and the dynamic aperture study is presented in detail.
基金supported by the National Natural Science Foundation of China(Nos.11575217,11527811)
文摘An experimental muon source is planned for the China Spallation Neutron Source.A simplified beamline with a limited number of magnets is achieved using a FODO lattice for implementation in a future preliminary stage.The yield of the muon delivered to the experimental sample is slightly larger than 10^5 μ^+/s within the FWHM beam spot(-φ30 mm)from a thick muon target.In addition,the beam polarization is 92%and the contamination that is mainly formed by positrons is approximately a fraction of 1%.
基金Project supported by the National Natural Science Foundation of China （Grant No 10525525）. The author would like to thank Xu G., Qin Q, Jiao Y for their helpful discussions.
文摘The International Linear Collider （ILC）, which is based on super-conducting RF acceleration technology, requires the damping rings to provide beams with extremely small equilibrium emittance, and large acceptance to ensure good injection efficiency for high-emittance, and high-energy spread beam from the positron source. In order to reduce the cost for ILC damping rings, an alternative lattice which is different from the baseline configuration design has been designed with modified FODO arc cells, and the total quadrupole number has been reduced by half. At the same time, to decrease the total cost involved in constructing access shafts needed to supply power, cryogenics etc. for the wigglers and other systems, the number of wiggler sections is decreased from 8 to 4, and further to 2. This new lattice has been optimized to have a good dynamic aperture. This alternative ILC damping ring lattice design will reduce the cost largely as compared with the baseline design.
