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参数进行了包含电子云效应的不稳定性分析.研究了J-PARC环的冲击参数.采用双质点模型和J-PARC参数，对带反馈阻尼器的头-尾不稳定性进行了稳定性分析.在KEK-12 GeV-PS主环上进行的注入能量（500 MeV）的实验（1）用一个监视器和一个冲击器进行反馈阻尼实验，用模拟电路成功地阻尼了一个头尾不稳定性（模式0，增长率~30 ms）。(2)应用并比较了数字信号处理（使用现场可编程门阵列的快速处理）和模拟信号处理。实现了类似的阻尼时间。(3)用单粒子模型分析了稳定性。(4)采用数字信号处理的双监控单冲击器反馈阻尼实验稳定了失稳。但是，由于RF放大器被大的剩余COD（闭合轨道失真）信号饱和，因此无法研究强阻尼效应。消除COD成分是下一个课题。双监视器双冲击器构型的分析（1）采用单粒子模型，得到了双监视器单冲击器构型稳定性的精确解。快阻尼区的解与小阻尼区的近似解有很大的不同，如果选取适当的参数，可以实现单匝或双匝阻尼。问题是（a）振荡幅度在初始幅度上增加了一段时间;（B）稳定区域受到限制。(2)采用单粒子模型，得到了双监视器双冲击器稳定性的数值解。以上两个问题在本案中都得到了解决。二粒子模型和多粒子模拟的分析是下一个主题。

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