激光加速电子束团的输出特性研究  

Output Characteristics of Electron Bunch Accelerated by Laser Pulse

作　　者：华剑飞[1] 霍裕昆[2] 曹娜[2] 林郁正[1] 

机构地区：[1]清华大学工程物理系,北京100084 [2]复旦大学现代物理研究所,上海200433

出　　处：《高能物理与核物理》2004年第3期308-312,共5页High Energy Physics and Nuclear Physics

基　　金：国家自然科学基金 ( 10 0 760 0 2 );国家重点基础研究基金 (G19990 75 2 0 0 )资助~~

摘　　要：通过仔细研究俘获加速CAS(captureandaccelerationscenario)机制中电子束团的输出特性 ,发现其出射电子有 3类不同的运动轨道即掠过 (pass by)、非弹性散射 (IS)、CAS .由于实际入射电子束团的线度远大于强激光脉冲的线度 ,因此只有位于入射电子束团中心区域的电子才可能被俘获加速 .对于目前所能获得的聚焦激光场强 (～ 10 2 1W cm2 )和实际的电子束团 (～ 10 8个电子 )而言 ,最大的输出能量可达到 4 5 0MeV以上 ,同时被加速电子的数目可达到 10 4— 10 5个 .This paper addresses the output characteristics of real electron bunches accelerated with ultra-intense laser pulse in vacuum by the capture and acceleration scenario (CAS) scheme. It shows that there exist three kinds of electrons' trajectories after the interaction between electron bunch and laser pulse, namely pass-by, inelastic scattering and CAS. Normally, as the size of an electron bunch is much larger than that of a tightly focused and compressed laser pulse, only those electrons located in the central region of the incident bunch can be accelerated to high energy. For a high intensity laser (～10 21W/cm 2) and an electron bunch (～10 8 electrons), the maximum electron energy gain from the laser field can be more than 450MeV, and the number of CAS electrons can reach to 10 4-10 5. These results demonstrate that CAS is promising to become a novel mechanism of vacuum laser accelerators.

关 键 词：俘获加速 激光加速 电子束团 输出特性 非弹性散射 动力学轨道 加速效率 

分 类 号：O572.2[理学—粒子物理与原子核物理]