CAJ | 학술논문

正电子湮没技术是一种研究材料的微观缺陷和相变的灵敏工具，在通常的正电子谱仪中，正电子能量为MeV量级，在样品中注入深度比较深(～100μm)，主要研究材料体内的平均缺陷密度.慢正电子束方法把正电子的能量降低为keV量级(而且可以调节)，注入比较浅(～μm)，所以是研究表面缺陷的探测手段.正电子慢化体是产生慢正电子的关键设备，对其研究有重要意义.文章综述了慢化体研究的历史和现状，从物理概念出发介绍使正电子慢化的四种可能方法和当今慢化体的五种几何排列方式.其中应用最广泛的是钨慢化体和百叶窗式的排列方式，效率最高的是惰性气体固体慢化体，而加电场慢化体是有待开发的高效慢化体.
정전자인몰기술시일충연구재료적미관결함화상변적령민공구，재통상적정전자보의중，정전자능량위MeV량급，재양품중주입심도비교심(～100μm)，주요연구재료체내적평균결함밀도.만정전자속방법파정전자적능량강저위keV량급(이차가이조절)，주입비교천(～μm)，소이시연구표면결함적탐측수단.정전자만화체시산생만정전자적관건설비，대기연구유중요의의.문장종술료만화체연구적역사화현상，종물리개념출발개소사정전자만화적사충가능방법화당금만화체적오충궤하배렬방식.기중응용최엄범적시오만화체화백협창식적배렬방식，효솔최고적시타성기체고체만화체，이가전장만화체시유대개발적고효만화체.
The positron annihilation technique is a sensitive tool for studying microdefects and phase transitions in various materials.Usually the energy of positrons is on the order of MeV and the implantation depth about 100 microns,so the bulk average defect density can be studied.In a slow positron beam the positron energy is about keV and the implantation depth a few microns,so surface defects can be detected.Positron moderator is the key device for obtaining a slow positron beam.We review the history and development of the positron moderator,including four methods that convert fast positrons into slow mono-energetic positrons and five array types.The tungsten moderator is the most widely used one while the inert gas solid moderator is the most efficient.Field-enhanced moderators with their high efficiency have great potential but need to be developed.The vane arrangement is the most commonly found.