Active Support for Linear Collider

为了获得足够高的亮度，下一代线性对撞机应该具有极小的发射度，例如1×10^<33>到1×10^<34> cm10^<-2>sec10^<-1>。相互作用点高度小于10纳米的光束尺寸非常小，因此这些机器对地面运动非常敏感，导致不相关的机器部件抖动。机器部件的精确对准对于防止发射度稀释至关重要。电子/正电子线性对撞机c波段（5712 Mhz）射频系统的硬件研发始于1996年KEK。这些进展已在国际会议上报告。报告称，加速结构的公差为30微米，聚焦元件的公差为1微米。在我们的研究中，我们为加速结构设计了主梁，主梁是由主动推杆支撑的。在进行设计的同时，我们还对宽频率范围内的地震动进行了研究，以获得切合实际的设计理念。为了补偿地面运动，采用新思路研制了主动支承式移动机构。我们已承诺对长期使用的移动设备进行质量检测。该动力装置由空气弹簧和多层橡胶轴承（MLRB）组成。与机械千斤顶相比，空气弹簧控制平稳、精细。为了防止地震引起的支撑梁的快速弹跳运动，我们采用了MLRB。采用LON控制器对该电机的控制系统进行了详细设计。本文采用有限元法对PC混凝土主梁进行了分析。

The next generation linear colliders should have extremely small emittance in order to achieve sufficiently high luminosity, such as 1×10^<33> to 1×10^<34> cm10^<-2>sec10^<-1>. The very small beam size of less than ten nanometers height at the interaction point is essential, then these machines are very sensitive to the ground motion leading to uncorrelated machine component jitter. Precise alignment of the machine components is essential to prevent emittance dilution. Hardware R＆D on the C-band (5712 Mhz) RF-system for the electron/positron linear collider started in 1996 at KEK.The progresses have been reported in the international conferences. The report said the tolerance of the accelerating structure is 30 microns and the tolerance of the focusing elements is 1 micron. In our study, we have designed the girder for the accelerating structures, the active movers which support the girder. In parallel to these design, we have also studied about the ground motion for wide frequency range to obtain the realistic design concept. In order to compensate the ground motion, an active supporting mover was developed using new idea. We have undertaken to test the quality for long term use of the mover. The mover is composed of an air-spring and a Multi-Layer-Rubber-Bearing (MLRB). The air-spring gives smooth and fine control comparing with the mechanical jack. We use MLRB to prevent fast popping motion of the supporting girder induced by earthquake. Detailed designs of the control system for the mover have been done using LON controller. We have made an analysis using the finite element method on the PC concrete girder.