Generation of high power, high frequency radiation using high brightness pseudospark-sourced relativistic electron beams

的主要目的是调查的伪火花放电产生的电子束脉冲具有最高的同时电流密度和亮度的任何已知类型的电子束源。在构建并运行了第一个基于赝火花放电的相干辐射源之后，我们最近测量了高电流密度（1.5kAcm [-2]）亮度为10[11]至10[12] Am[-2]rad[-2]的电子束，建议的计划旨在提高我们对物理学的理解伪火花放电随着等离子体阴极的尺寸减小而产生，第一次传输具有异常电流密度和束质量的小（mm和亚mm）直径电子脉冲。可以从数百GHz到THz频率范围内的自由电子辐射源产生的功率受到以下事实的限制：随着频率的增加，必须减小相互作用的直径，以防止微波激射器变得过模，从而导致输出辐射的时间和空间相干性的损失。相互作用区域尺寸的减小使得使用常规阴极聚焦并形成通过高频微波激射器的小尺寸相互作用区域的高电流密度、高质量电子束变得越来越困难（如果不是不可能的话）。我们的目的是联合收割机结合三个领先的大学研究小组在以下领域的集体知识和专业知识：1）伪火花物理学，2）毫米波源的计算建模和太赫兹组件的设计，以及3）先进的毫米波制造技术，以研究使用伪火花源电子束脉冲来产生高功率，通过速调管（200 GHz）的高频相干电磁辐射和后向波（390 GHz至1 THz）不稳定性。

The principle aim is the investigation of the pseudospark discharge resulting in the generation of electron beam pulses with the highest simultaneous current density and brightness of any known type of electron beam source. Having constructed and operated the first coherent radiation source based on a pseudospark discharge, we have recently measured a high current density (1.5kAcm [-2]) electron beam of brightness 10[11] to 10[12] Am[-2]rad[-2], the proposed programme aims to enhance our understanding of the physics the pseudospark discharge as the size of this plasma cathode is reduced and to produce and transport for the first time small (mm and sub-mm) diameter electron pulses of exceptionally current density and beam quality. The power that can be generated from free electron radiation sources in the hundreds of GHz to THz frequency range has been limited by the fact that as the frequency is increased, the diameter of the interaction has to be reduced in order to prevent the maser becoming overmoded resulting in a loss of the temporal and spatial coherence of the output radiation. The reduction in the size of the interaction region makes it increasingly difficult (if not impossible) using conventional cathodes to focus and form high current density, high quality electron beams through the small size interaction region of a high frequency maser. It is our intention to combine the collective knowledge and expertise of three leading university research groups in the fields of 1) pseudospark physics, 2) computational modelling of millimetre wave sources and design of THz components and 3) advanced millimetre wave manufacturing technologies, to investigate the use of pseudospark sourced electron beam pulses to generate high power, high frequency coherent electromagnetic radiation via the klystron (200GHz) and backward wave (390GHz up to 1THz) instability.