本项目是为一台紧凑型低能离子直线加速器做探索性研究，这台加速器采用"离子源+IH漂移管"加速结构，将离子源产生的数十keV能量的离子束直接注入到具有极高分流阻抗的IH加速结构，避免了RFQ的使用，与传统的"离子源+RFQ+阿瓦列兹漂移管"结构相比，具有结构紧凑、造价低等优点。其主要加速聚焦方式采取了国际目前较热门的IH漂移管结构以及交变相位聚焦原理。本项目从两方面对设计这种结构的加速器的关键问题进行研究。一方面为极低注入能量的交变相位聚焦IH漂移管加速器束流动力学研究。第二方面为IH结构的设计和实验研究。受俘获效率所限，这类型加速器可能难以产生较大（数十mA级）的宏脉冲流强，但在不需要高的宏脉冲流强的场合（如PET同位素制备、PIXE、快中子照相等），本项目所提出的加速器结构将可以得到应用。本项目的研究内容属于具有一定开创性的研究。

This project is focused on a novel low energy ion accelerator schema in which the ion beam is injected directly from an ion source to an alternative phase focused IH acceleration sturcture. As we know, the IH sturcture has very high shunt impedance in low beta range. Comparing to the conventional accelerator schema consist of a RFQ, the accelerator schema pointed out by this proposal will have the advantage of compactness and low cost. The accelerator schema in this proposal employ alternative phase focus (APF) method. After realized the key problems in designing such an accelerator system, we will mainly perform two research work in this project. The first one is the particle dynamics design and optimization of an IH stucture with extremly low injection energy. The second one is design and experimental research on the RF properties of an IH strucute tank, such as RF simulation, frequency tuning and field distribution tuning. Because of the low capture efficiency, this accelerator schema may can not satisfy the cases in which high macro pulse current is needed, such as an injector of a synchrotron. But in some other cases, such as PIXE, isotope production and fast neutron image, the accelerator schema in this proposal probably can satisfy the need. The accelerator schema in this proposal is an original innovation.