次级倍增电子枪是一种利用次级电子倍增效应产生电子束的冷阴极微波电子枪。它可以产生强流、短脉冲的电子束，具有启动快、结构简单、寿命长、耐污染等优点，可以形成紧凑而高效的微波产生系统，也可以用于小型工业和医用加速器，是正在发展中的新型电子源。 本文给出了次级倍增电子枪的束流动力学分析，阴极材料的选择和制备，冷测、热测实验，以及新电子枪设计等内容。 首先介绍了次级倍增电子枪的基本原理、特点和应用以及国内外研究现状。然后分析了次级倍增电子枪的束流动力学，包括次级电子倍增效应概述、单粒子动力学、束流集体效应、瞬态束流负载效应、低气压次级电子倍增放电、模拟计算等。 阴极材料是次级倍增电子枪的关键技术。首先介绍了次级电子发射的特性和物理机制，然后介绍了合金、氧化镁、金刚石等阴极材料的电子发射特性和制备工艺，设计了次级电子发射系数测量装置并进行了初步测量实验。 在动力学研究和材料学研究的基础上，进行了次级倍增电子枪的实验研究，包括微波特性参数测量、原理验证实验、高功率热测实验和阴极寿命试验等。采用氢终止的化学气相沉积（CVD）金刚石薄膜作为阴极材料，在以磁控管为微波功率源的出束实验中得到了920 mA的宏脉冲电流。 最后，为了方便进一步的定量实验，初步设计了工作在TE102模式，并带有在线调距、调谐等装置的新的次级倍增电子枪。
The Multipactor Electron Gun (MEG) is a cold cathode RF gun based on the multipactor effect. It can produce short duration, high current electron beams. MEG has many advantages such as fast response, simple structure, long lifetime and tolerance to contamination. It can form a compact and efficient microwave system, or can be used in the small industrial and medical accelerators, thus it is a promising electron source. This thesis presents our work on the dynamic theory, cathode preparation, cold and hot tests of MEG as well as the design of a new gun. First, the principle, application and the research status of MEG are given. Then the beam dynamics is investigated, including the review of multipactor effect, single electron dynamics, space charge effect, transient beam loading effect, multipactor in low pressure gas and the simulation. Cathode material is the key point of making an MEG. First the secondary electron emission mechanism is introduced and then the properties and preparations of metal alloy cathodes (MAC), MgO and diamond films are discussed, and the best cathode materials are carefully selected according to different application areas. Measurement of the secondary electron emission yield is also performed. Based on the dynamic and material studies, the experimental investigation is presented, including RF measurement, proof-of-principle experiment, high power experiment and the life test of cathodes. A macro-pulse current of 920 mA was observed in the hydrogen terminated CVD diamond MEG experiment using a magnetron. Finally a new gun working in TE102 mode with online gap-adjuster and tuner is designed.
