The electron accelerators for the AWAKE experiment at CERN-Baseline and Future Developments
The electron accelerators for the AWAKE experiment at CERN-Baseline and Future Developments
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DOI：
10.1016/j.nima.2018.02.044
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发表时间：
2018-11-12
影响因子：
1.4
通讯作者：
Mitchell, J.
中科院分区：
文献类型：
--
作者：
Pepitone, K.;Doebert, S.;Mitchell, J.
AWAKE合作准备在CERN使用SPS束进行质子驱动等离子体韦克菲尔德加速实验。从SPS中提取的长质子束与高功率激光和10米长的铷蒸气等离子体单元相互作用，以产生强尾场，从而允许持续的电子加速。探测这些尾流场的电子束由一个由射频枪和助推器结构组成的电子加速器产生。该电子源应提供强度在0.1和1 nC之间、聚束长度在0.3和3 ps之间并且发射度为2 mm mrad的束。助推器结构应该将电子加速到16 MeV。电子线包括一系列的诊断（胡椒罐，BPM，光谱仪，法拉第杯和屏幕）和光学传输线合并电子束与质子束在同一轴上。电子线的安装于2017年初开始，调试将于2017年底进行。运行的第一阶段称为RUN 1。在LHC长期关闭之后，计划从2021年开始进行第二阶段的AWAKE，称为RUN2。在这一阶段的目的是证明高品质的电子束的加速，因此需要对应于等离子体波长的一小部分的100 fs rms的数量级的聚束长度。AWAKE合作正在研究这种注入器的设计，无论是基于经典的射频枪注入器还是激光尾场加速。RF加速器的重点是使用S波段RF枪和X波段聚束和加速腔的混合设计。目前和未来的电子加速器和传输线的布局，包括诊断将被提出。
The AWAKE collaboration prepares a proton driven plasma wakefield acceleration experiment using the SPS beam at CERN. A long proton bunch extracted from the SPS interacts with a high power laser and a 10 m long rubidium vapor plasma cell to create strong wakefields allowing sustained electron acceleration. The electron beam to probe these wakefields is created by an electron accelerator consisting of an rf-gun and a booster structure. This electron source should provide beams with intensities between 0.1 and 1 nC, bunch lengths between 0.3 and 3 ps and an emittance of the order of 2 mm mrad. The booster structure should accelerate the electrons to 16 MeV. The electron line includes a series of diagnostics (pepper-pot, BPMs, spectrometer, Faraday cup and screens) and an optical transfer line merges the electron beam with the proton beam on the same axis. The installation of the electron line started in early 2017 and the commissioning will take place at the end of 2017. The first phase of operation is called RUN1. After the long shutdown of LHC a second phase for AWAKE is planned starting 2021 called RUN2. In this phase the aim is to demonstrate the acceleration of high quality electron beams therefore a bunch length of the order of 100 fs rms is required corresponding to a fraction of the plasma wavelength. The AWAKE collaboration is studying the design of such an injector either based on classical rf-gun injectors or on laser wake-field acceleration. The focus for the RF accelerator is on a hybrid design using an S-band rf-gun and x-band bunching and acceleration cavities. The layout of the current and the future electron accelerator and transfer line, including the diagnostics will be presented.