共查询到19条相似文献,搜索用时 93 毫秒
1.
2.
3.
根据同步光与储存环中的束流信号具有相同的时间结构的原理,测量同步光脉冲的半高全宽值可以计算出束团的长度。根据合肥光源的特点和实际需要,选择快速光电接收器搭配高速高带宽示波器作为在线测量束团长度和纵向分布等的主要手段。对单束团模式下束团长度随流强和高频腔腔压的变化趋势进行了测量。测量结果表明:束团长度与腔压的0.3次方成反比,比理论值0.5小;而束团长度随流强的增长率为2.0 ps/mA。通过测量纵向量子寿命进行了能散随流强变化的间接测量,结果表明,束团的拉伸是能散变化和势阱效应共同作用的结果。 相似文献
4.
根据同步光与储存环中的束流信号具有相同的时间结构的原理,测量同步光脉冲的半高全宽值可以计算出束团的长度。根据合肥光源的特点和实际需要,选择快速光电接收器搭配高速高带宽示波器作为在线测量束团长度和纵向分布等的主要手段。对单束团模式下束团长度随流强和高频腔腔压的变化趋势进行了测量。测量结果表明:束团长度与腔压的0.3次方成反比,比理论值0.5小;而束团长度随流强的增长率为2.0 ps/mA。通过测量纵向量子寿命进行了能散随流强变化的间接测量,结果表明,束团的拉伸是能散变化和势阱效应共同作用的结果。 相似文献
5.
通过求解D2分子在飞秒激光场中的含时薛定谔方程,研究了室温下D2分子在超快飞秒激光驱动下的的转动波包动力学. 选择用第一束超短飞秒脉冲与温度为300 K的D2分子系综相互作用产生一个相干转动波包,用第二束超短飞秒脉冲在波包的1/4和3/4恢复周期选择操纵D2分子取向. 研究结果表明,通过选择两束超短飞秒脉冲的延迟时间,可以有效控制D2分子转动波包中奇偶态的相对布居,从而选择性的控制D2分子取向. 相似文献
6.
设计了用于PKU-FEL注入器的腔式位置诊断装置。该BPM腔采用的偶极模TM110模的频率与PKU-FEL主加速器的基模频率一致,都是1.3 GHz;通过在圆形腔上镶入两个完全一致的矩形腔解决了腔式BPM的Cross-Talk问题。 根据PKU-FEL的设计要求,所设计的BPM腔的最小位置响应约10 mm,动态范围大于30 mm,时间响应小于束团间距。还估算了该BPM腔引起的束团功率损耗。结果表明,BPM腔引起的束团功率损耗是可以忽略的。 相似文献
7.
8.
9.
10.
11.
R. Kuroda N. Sei M. Yasumoto H. Toyokawa H. Ogawa M. Koike K. Yamada 《Infrared Physics & Technology》2008,51(5):390-393
The 0.1 THz coherent synchrotron radiation (CSR) was successfully generated in the 90° bending magnet of the compact S-band linac with the achromatic arc section using the ultra-short electron bunch which has the energy of 40 MeV, the bunch charge of about 1nc and the bunch length less than 1 ps (rms). The electron bunch compression of 1 nC electron bunch was achieved less than 1 ps (rms) by controlling the Q-magnets in the achromatic arc section as the bunch length was measured by the rms bunch length monitor. 相似文献
12.
提出了一种基于高次模式的谐振腔束团长度测量技术,新方法的谐振腔工作于高次本征模式TM0n0。这样的谐振腔拥有更大的腔体半径,从而移除了谐振腔半径必须大于束流管道半径这一原则带来的工作频率限制。为国家同步辐射实验室未来的正电子源设计了一台双腔束团长度监测器,讨论了谐振腔工作频率的选择并推导了束团长度的计算公式,监测器的谐振腔工作于TM020模式,其半径远大于使用TM010模式的传统方法,在CST软件中模拟的结果显示其束团长度测量精度好于7%。 相似文献
13.
For performing mini-β scheme in the Beijing Electron-Positron Collider (BEPC),high RF voltage is supplied for shortening the bunch length,but results in the luminosity decrease. This is the special phenomenon of beam-beam on BEPC, which limits the performance of mini-β scheme. The work is aiming to explain the special phenomenon and overcome it. The conclusion of theoretic analysis,simulation and machine study is that,for BEPC,the bunch length influences the beam-beam interaction mainly through the “hourglass”effect and a veraging over the betatron phase during the collision, and these two contrary effects make the luminosity to be maximum only when σs/βy (the ratio of bunch length and beta function of y-direction) is near the optimal value, and so the luminosity decrease due to high RF voltage can be avoided. 相似文献
14.
Experimental Characterization of Sub-picosecond Electron Bunch Length with Coherent Diffraction Radiation 总被引:1,自引:0,他引:1 下载免费PDF全文
XIANG Dao YANG Xing-Fan HUANG Wen-Hui TANG Chuan-Xiang LIN Yu-Zheng LI Wei-Hua PAN Qing LI Ming 《中国物理快报》2008,25(7):2440-2443
Diffraction radiation is one of the most promising candidates for electron beam diagnostics for the International Linear Collider, x-ray free electron lasers and energy recovery linac due to its non-intercepting characteristics. We report the non-intercepting measurement of sub-ps electron bunch length with coherent diffraction radiation. The bunch length is measured with a Martin--Puplett interferometer and the detailed longitudinal bunch shape is reconstructed with the Kramers--Kronig relation. The rms bunch length is found to be about 0.73ps, which confirms a successful commissioning of the bunch compressor and the interferometer. 相似文献
15.
ZHANG Jing-Ru DAI Jian-Ping GU Qiang PEI Guo-Xi ZHAO Ming-Hua ZHONG Shao-Peng WANG Xing-Tao CHEN Yong-Zhong HOU Mi 《中国物理C(英文版)》2010,34(1):138-142
RF deflectors can be used for bunch length measurement with high resolution. This paper describes a completed S-band traveling wave RF deflector and the bunch length measurement of the electron beam produced by the photocathode RF gun of the Shanghai DUV-FEL facility. This is the first time that such a transverse RF deflector has been developed and used to measure the bunch length of picosecond order in China. The deflector's VSWR is 1.06, the whole attenuation 0.5 dB, and the bandwidth 4.77 MHz for VSWR less than 1.1. With a laser pulse width of 8.5 ps, beam energy of 4.2 MeV, and bunch charge of 0.64 nC, the bunch lengths for different RF input power into the deflector were measured, and an averaged rms bunch length of 5.25 ps was obtained. A YAG crystal is used as a screen downstream of the deflector, with the calibrated value of 1 pix = 136 μm. 相似文献
16.
17.
The Electro-optical sampling delay scanning technique can be used for electron beam bunch length measurement.A novel non-synchronous delay scanning technique based on the electro-optical sampling measurements is presented.Based on Beijing Free Electron Laser(BFEL),the electron beam bunch length was measured with the electro-optical sampling technique for the first time in China.The result shows that the electron beam bunch length at BFEL is about 5.6±1.2 ps. 相似文献
18.
基于直流电子枪-超导加速腔(DC-SC)光阴极注入器样机的初步实验结果,北京大学提出了新的注入器的改进设计。新注入器核心结构包括皮尔斯枪和3+1/2超导腔。文章给出了它们的详细结构参数,然后采用程序,对注入器的束流动力学进行了模拟。结果发现:新注入器可以提供具有高束流品质、高平均流强的电子束,束团的电荷量100 pC,横向发射度低于2 mm·mrad,脉宽5 ps,rms束斑可达0.5 mm,重复频率81.25 MHz;也可以提供电荷量为300 pC低重复频率的高峰值流强的电子束,其横向发射度小于3 mm·mrad,脉宽约为9 ps,以满足北京大学自由电子激光(PKU-FEL)实验平台的要求。 相似文献