基于常数广义角动量阴极面的大回旋轨道电子注发射系统

项目名称： 基于常数广义角动量阴极面的大回旋轨道电子注发射系统

项目编号： No.11275206

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 数理科学和化学

项目作者： 杜朝海

作者单位： 北京大学

项目金额： 79万元

中文摘要： 基于远程高分辨率雷达、毫米波拒止武器、热核聚变等离子体加热等领域对高功率毫米波-太赫兹波功率源的迫切需求，项目提出研究基于常数广义角动量（AGM）阴极面的磁会切电子发射系统，解决高次谐波回旋管难以获得高功率、低速度离散大回旋轨道电子注之难题。通过匹配阴极区磁位型，构建常数AGM阴极面，使得初始发射电子具有相同的AGM，优化阴极区聚焦加速电场，以平衡电子注引导中心偏移和空间电荷场，能够大幅度扩展磁会切电子枪的阴极面相对宽度，获得速度离散小于3%的高功率大回旋轨道电子注。结合实验室阴极工艺技术，发展高功率低速度离散的磁会切电子枪。采用YAG晶体成像方法分析电子注参数，并将该电子枪应用于396GHz四次谐波TE41模式回旋管验证理论研究成果。常数AGM阴极面能够显著提高磁会切电子枪阴极面相对宽度，提高电子注电流和降低速度离散，发挥高次谐波回旋管高功率和低磁场的优势，促进高功率毫米波源的发展。

中文关键词： 太赫兹；回旋管；高次谐波；大回旋电子枪；正则角动量

英文摘要： Based on urgent needs on high power millimeter-wave- to-terahertz-wave sources from applications， including high resolution radar, millimeter-wave active denial weapon, fusion plasmas heating, it is proposed to study Magnetic Cusp electron Gun (MCG) based on a constant Angular Generalized Momentum (AGM) cathode emitter surface,as a way of solving the problem that it is difficult to obtain high power and low velocity spread Large-Orbit Electron Beam (LOB). This novel magnetic cusp gun employs a constant AGM cathode emitter surface constructed by carefully matching the magnetic field, and emits electrons with monolithic initial AGM. Through opimizing the focusing-accelerating electric field to balance the guiding center spread and space charge field, it is capable of widen the emitter surface and generating ideal luminar LOB simultaneously with high power and low velocity spread. With the support from cathode technique of our Lab, we are going to develop a high power magnetic cusp gun. Electron beam parameters will be diagnosised by YAG crystal imaging technique,and this gun will be installed in a 396GHz 4th harmonic TE41 mode gyrotron to verify the theoretical research achievement. The scheme of constant AGM cathode emitter surface obviously widens the relative width of a MCG cathode surface, enhances the eletron

英文关键词： terahertz；gyrotron；high harmonic；large-orbit electron gun；canonical angular momentum