论文标题
比例计数器和微通道板
Proportional counters and microchannel plates
论文作者
论文摘要
比例计数器是在1940年代开始时期开发的,是X射线天文学中使用的第一个检测器,并将其主力保留了将近四十年。尽管这种检测器的原理似乎很简单,但随着时间的流逝,它经过了相当大的性能改善,并且在轨道条件下的寿命大大延长了。特别是对位置敏感比例计数器的发明提供了新的和复杂的方法,以区分背景,从而实现了较弱的来源的观察。 随着1970年代的微通道板(MCP)探测器的出现,实现了位置分辨率的飞跃。与填充气体探测器相反,它们没有提供可观的能量分辨率,但具有空间分辨率,达到了几十微米,理想情况下,新型放牧入射率成像X射线望远镜的角度分辨率即将到来。 即使在今天,两种类型的探测器仍在太空天文学中均具有相关性。但是,如果MCP的新发展集中在遥远和极端的紫外线范围上,而Chandra X射线观测站很可能是将该技术应用于X射线的最后一次任务。相比之下,使用气体电子乘数(GEM)箔和微图案读数的紧凑型检测器目前在软X射线范围内正在进行重大开发,因为它们首次允许在广泛的能量范围内测量X射线极化。 本章介绍了比例计数器和MCP检测器的原理,突出了各自的性能特征,并总结了它们在X射线天文学中最重要的应用。
Developed right at the beginning of the space age in the 1940s, the proportional counter was the first detector used in X-ray astronomy and stayed its workhorse for almost four decades. Although the principle of such a detector seems to be rather simple, over time it underwent considerable performance improvements and the lifetime under orbital conditions was extended tremendously. Particularly the invention of position-sensitive proportional counters provided new and sophisticated methods to discriminate background and thus enabled observations of much weaker sources. A leap forward in position resolution was achieved with the advent of microchannel plate (MCP) detectors in the 1970s. In contrary to gas filled detectors, they provide no considerable energy resolution but feature spatial resolutions reaching down to a few tens of micrometers, fitting ideally the angular resolution of the novel grazing incidence imaging X-ray telescopes upcoming at that time. Even today, both types of detectors are still relevant in space-based astronomy. However, in case of MCPs new developments focus on the far and extreme ultraviolet wavelength range, while the Chandra X-ray observatory is most likely the last mission applying this technology for X-rays. In contrast, compact detectors with gas electron multiplier (GEM) foils and micropattern readout are currently under heavy development for the soft X-ray range, since they allow for the first time to measure polarization in X-rays over a broad energy range. This chapter presents the principles of proportional counters and MCP detectors, highlights the respective performance characteristics, and summarizes their most important applications in X-ray astronomy.