面向太阳空间观测的ΔE-E带电粒子探测器设计的模拟研究

The charged particle detector with the ability of particle identification and energy measurement is a kind of essential and significant instrument to carry out science observation and guarantee safe and reliable working of equipment in space observation. On the other hand, the program about solar space observation developed by our country will be performed in several years to come, which raises the requirement of the charged particle detector suitable for the mission. Considering this background, we plan to make a computer Monte Carlo simulation for a prototype of a ΔE-E detector in the project and present a optimization design of the detector by simulation. The feasibility and reliability of algorithm of particle identification will be verified using the data generated through the simulation. Furthermore, the effects to the performance of detector originated from the realistic factors will also be accessed in the study. Finally, a optimization design of the detector which fulfills the physical requirement of solar space observation will be determined by repeated simulation and modification of structure of the detector. The results and data of this study will not only provide an overall and direct reference to the future actual development of the detector, but also promote the development of space science.

在空间探测研究中，可以进行粒子鉴别和能谱测量的带电粒子探测器是进行科学观测和保障设备安全的必不可少的重要设备。即将开展的太阳空间观测对带电粒子探测器提出了相应的科学需求，为了稳步的开展面向太阳观测的ΔE-E带电粒子探测器的研制，我们的课题拟提出借助计算机蒙特卡罗仿真分析该探测器粒子鉴别性能，并以此来进行该探测器的优化设计。首先将通过模拟产生的数据检验基本的粒子鉴别算法的可行性和可靠性，进而考虑空间中各种因素对探测器性能的影响，通过不断的模拟和优化，修改探测器结构，最终使得探测器具备满足太阳观测提出的物理需求的性能指标。研究取得的研究成果，包括探测器设计数据和性能指标信息将给探测器将来的实际研制提供全面和直接的参考，对空间科学的发展也有积极的推动意义。

太阳带电粒子探测器是太阳观测科学卫星的常用载荷，可以用来对来自太阳爆发的带电粒子进行原位探测，深入研究太阳活动机制等科学问题，同时也可以完成监测空间环境的任务，保障卫星本体安全。我们采用蒙特卡洛的手段，开展了dE-E带电粒子探测器的计算机模拟和设计，通过粒子鉴别能力和误判率等指标的约束，对探测器尺寸及鉴别方法的参数进行了优化，得到一台包括准直器，四片硅探测器（厚度分别为150微米，150微米，300微米，3000微米）和溴化镧晶体量能器和反符合探测器的原型设计方案，该方案对电子，质子和部分核素都具有较强的鉴别能力，完全适应空间环境要求，可以作为后续设计研究的起点。另外，我们还针对太阳观测的需求，对国外相关太阳带电粒子探测载荷进行了广泛调研，比如STERO/SEPT和Solar Orbiter/EPT载荷的方案采用磁场和parylene薄膜来分别压低电子和质子本底，同时采用高性能的硅探测器实现了20~30keV电子和70keV质子的探测。借鉴其方案，我们将在后续研究中继续探索如何降低探测器能窗下限，满足太阳科学研究中对几十keV带电粒子观测的需求。