Design Study of a Coupling RF Cavity for Three-Dimensional Laser Cooling

三维激光冷却耦合射频腔的设计研究

• 批准号: 09554011
• 负责人: OKAMOTO Hiromi
• 金额: $ 7.17万
• 依托单位: Hiroshima University (1998-1999)Kyoto University (1997)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09554011/
• 关键词: Laser Cooling; Storage Ring; Crystalline Beam; Coupling Cavity; Tapered Cooling

The purpose of this project is to develop a novel three-dimensional laser cooling scheme for fast stored ion beams. The main results obtained during the term of the project are :1. It has been numerically demonstrated, with the tracking code "SAD" and molecular dynamics code "SOLID", that longitudinal laser cooling force can be extended to the transverse degrees of freedom of beam motion by employing the resonant coupling method.2. A low-power model of coupling RF cavity was designed and fabricated.3. It has been shown that the storage-ring lattice suitable for beam crystallization must satisfy the following two conditions : (a). the phase advance of betatron oscillation per lattice period is below about 127 degrees, and (b). the beam energy is less than the transition energy of the ring.4. Provided that the above-mentioned conditions are fulfilled, it is possible to produce an ultra-cold beam by means of the resonant coupling method.5. The relation between intra-beam heating rate and the amount of focusing field errors was studied.6. It has been concluded that, in order to stabilize a crystalline beam, a tapered cooling force is necessary.7. In order to generate a tapered light, a possible cooling scheme using multiple lasers has been proposed, and its validity was tested with molecular dynamics simulations.

本计画的目的是发展一种新颖的三维雷射冷却方案，以应用于快速储存离子束。在项目实施期间取得的主要成果是：1.采用SAD跟踪程序和SOLID分子动力学程序，数值模拟了激光纵向冷却力可以通过共振耦合方法扩展到光束运动的横向自由度.设计并制作了一种低功耗的耦合腔模型.研究表明，适合束流结晶的储存环晶格必须满足以下两个条件：（a）。每个晶格周期的电子感应加速器振荡的相位超前低于约127度，以及（B）。射束能量小于环的跃迁能量。只要满足上述条件，就有可能通过共振耦合方法产生超冷梁。研究了束内加热速率与聚焦场误差量的关系.已经得出结论，为了稳定晶体梁，锥形冷却力是必要的。为了产生锥形光，已经提出了一种可能的冷却方案，使用多个激光器，其有效性进行了测试与分子动力学模拟。

项目成果

H.Okamoto: "Simulation Study of halo Formation in Breathing Round Beams" Physical Review. E55 No.4. 4694-4705 (1997)

H.Okamoto：“呼吸圆梁光晕形成的模拟研究”物理评论。

J.Wei: "Necessary Conditions for Attaining a Crystalline Beam" Physical Review Letters. (発表予定).

J. Wei：“获得晶体光束的必要条件”物理评论快报（即将出版）。

T.Kihara,et al.: "Simulation Study of Three-dimensional Laser Cooling Schemes for Fast Stored Beams"ICR Annual Report. Vol.5. 54-55 (1998)

T.Kihara等人：“快速存储光束三维激光冷却方案的模拟研究”ICR年度报告。

H. Okamoto, et al.: "Theory of Tapered Cooling"Physical Review E. Vol. 58, No. 3. 3817-3825 (1998)

H. Okamoto 等人：“锥形冷却理论”物理评论 E. 卷。

T.Kihara,et al.: "The Coupling-Cavity Scheme for Three-Dimensional Laser Cooling"Proc.1997 Particle Accelerator Conf.. 1798-1800 (1998)

T.Kihara 等人：“三维激光冷却的耦合腔方案”Proc.1997 Particle Accelerator Conf.. 1798-1800 (1998)