Hadron Accelerator improvement toward high intensity and hi8gh brightness beams

强子加速器向高强度和高亮度光束的改进

• 批准号: 16540272
• 负责人: TOYAMA Takeshi
• 金额: $ 1.28万
• 依托单位: High Energy Accelerator Research Organization
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2004
• 资助国家: 日本
• 起止时间: 2004 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-16540272/
• 关键词: collective beam instability; feedback damper; electron-cloud; head-tail instability

1. Instability analysis including the electron cloud effect was performed using the KEK-PS and J-PARC parameters.2. A kicker parameter was studied for the J-PARC ring.3. Stability analysis of the head-tail instabilities with feedback dampers, using two-particle model, and the J-PARC parameters.4. Experiments at the KEK-12 GeV-PS Main Ring at the injection energy (500 MeV)(1) Experiment of feedback damping with one monitor and one kicker.Succeeded in damping a head-tail instability ( mode 0, growth-rate ~30 ms) using an analog circuit.(2) A digital signal processing (fast processing with a Field Programmable Gate Array) and an analog signal processing were applied and compared. Similar damping times were achieved.(3) Stability was analyzed with one-particle model.(4) Experiment of feedback damping with two monitors and one kicker with a digital signal processingThe instability was stabilized. But strong damping effect could not be studied because the RF amplifier was saturated with a large remaining COD (closed orbit distortion) signal. Elimination of the COD component is the next subject.5. Analysis of two-monitor and two-kicker configuration(1) Exact solution was obtained for the stability with two monitors and one kicker, using one particle model. The solution for the fast damping regime is far different from the approximate solution for the small damping regime, and realizes one-or two-turn damping if appropriate parameters are chosen. Issues are (a) oscillation amplitude increases over the initial amplitude for a moment; (b) the stability region is restricted.(2) The numerical solution was obtained for the stability with two monitors and two kickers, using one particle model. Both above issues are resolved in this case. Analysis with the two-particle model and multi particle simulation is the next subject.

1.利用KEK-PS和J-PARC参数进行了考虑电子云效应的不稳定性分析。研究了J-Parc环的Kicker参数。利用双质点模型和J-PARC参数对带反馈阻尼器的头尾不稳定性进行稳定性分析。在KEK-12GeV-PS主环上进行了注入能量(500 MeV)下的实验。(1)用一个监视器和一个突击器进行反馈衰减实验，成功地用模拟电路抑制了头-尾不稳定(模式0，增长率~30ms)。(2)数字信号处理(用现场可编程门阵列进行快速处理)和模拟信号处理进行了比较。(3)采用单粒子模型进行稳定性分析。(4)采用数字信号处理技术对两台监控器和一台Kicker进行反馈减振实验，稳定了系统的不稳定性。但由于射频放大器被大量剩余的闭合轨道失真(COD)信号饱和，无法研究强衰减效应。下一个主题是消除化学需氧量成分。两监控器、两激励器配置的分析(1)采用单质点模型，得到了两监控器、一激励器的稳定性的精确解。快速阻尼区的解与小阻尼区的近似解有很大的不同，只要选取合适的参数，就可以实现一圈或两圈的阻尼。问题是(A)振荡幅度在初始幅度上增加了一瞬间；(B)稳定区域是受限的。(2)采用单质点模型，得到了具有两个监控器和两个Kicker的稳定性的数值解。在这种情况下，上述两个问题都得到了解决。用两粒子模型和多粒子模拟进行分析是下一步的主题。

项目成果

Feedback damping of the transverse head-tail instability

横向头尾失稳的反馈阻尼

• 发表时间: 2006
• 期刊: KEK Internal Report, Study Report SR-588
• 作者: 外山 毅;他;Takeshi Toyamaet al.
• 通讯作者: Takeshi Toyamaet al.

横方向ヘッドテール不安定性のフィードバックによる抑制

横向头尾不稳定性的反馈抑制

• 发表时间: 2006
• 期刊: KEK Internal Report SR-588
• 作者: 外山 毅;他
• 通讯作者: 他

Study of Impeda Instability for a Coasting Proton Beam in Circular Accelerators

圆形加速器中滑行质子束的阻抗不稳定性​​研究

• 期刊: Proc. of EPAC2004
• 作者: T. Toyama;K. Ohmi;Y. Shobuda
• 通讯作者: Y. Shobuda

KEK-PS MRでの横方向フィードバック・ダンパー実験

使用 KEK-PS MR 进行横向反馈阻尼器实验

• 发表时间: 2006
• 期刊: 第3回加速器学会プロシーディングス
• 作者: 外山 毅;他
• 通讯作者: 他

Simulation of Ep Instability for a Coasting Proton Beam in Circular Accelerators

圆形加速器中滑行质子束的 Ep 不稳定性模拟

• 发表时间: 2004
• 期刊: Proc.of EPAC2004
• 作者: K. Ohmi;T. Toyama;G. Rumolo
• 通讯作者: G. Rumolo