暗物质粒子探测卫星的宇宙线核素数据分析与科学研究

DArk Matter Particle Explorer (DAMPE) of China has the advantages of wide energy range, high energy resolution and high charge resolution. The launch of DAMPE provides new opportunities for cosmic ray research. In recent years, several space cosmic ray detectors, such as PAMELA, AMS-02, and Fermi, have found that at the energy range from several hundred GeV/n to several TeV/n, the spectra and secondary/primary ratios of different cosmic ray compositions differ from the results predicted by current cosmic ray models. One main goal of current cosmic ray research is to clarify these phenomena and to search for the underlying physical nature. In this project, we will analyze cosmic ray data measured by DAMPE to derive the refined spectra of cosmic ray nuclei with the energy up to 100TeV, and to get the secondary-to-primary ratios, such as B/C, up to 10TeV/n. In addition, we plan to search for exotic particles, such as fractional charged particles and monopoles, to determine the upper limit of these particles in cosmic rays. One can expect that some results of this project will have important impacts on particle astrophysics.

中国的暗物质粒子探测卫星具有宽能段、高能量分辨、高电荷分辨等特点。它的发射为研究宇宙线提供了新的良机。近年来，PAMELA、AMS-02、Fermi等空间宇宙线探测器的观测数据均显示在从几百GeV/n到几TeV/n能量段各种宇宙线成分的能谱和比例谱都存在与现有宇宙线模型不一致的迹象。澄清这些新现象并探索其蕴含的物理本质是当前宇宙线研究的一个主要目标。本项目将分析暗物质粒子探测卫星的数据，提取能量直到100TeV的宇宙线核素能谱和能量直到10TeV/n的次级／初级比例谱(如B／C比)，寻找可能存在的新结构，并对测量结果进行科学研究。此外，本项目还将对分数电荷粒子、磁单极子等奇异粒子进行搜索，确定它们在宇宙线中的上限。预期本项目的部分研究成果将对粒子天体物理产生重要的影响。

测量从氢到铁的宇宙线原子核精确能谱是暗物质粒子探测卫星的主要科学目标。本项目围绕暗物质粒子探测卫星的科学数据开展了如下研究:(1)对PSD,STK,BGO等子探测器进行了详细的在轨标定,完成了PSD的电荷重建和BGO的能量校正工作; (2)对Geant4模型和Fluka模型进行了详细的模拟和广泛的比较,确定了大规模模拟所需的物理模型并获得了大量的模拟数据; (3)完成了质子和氦核的能谱分析,并开展了B/C比和C、O和Fe核的能谱分析; (4)完成了用PSD测量重核的加速器束流实验以及分数电荷的搜寻工作;(5)把DAMPE的高精度质子能谱与其他探测器的测量结果结合起来对宇宙线的起源进行了理论分析。本项目的研究成果对宇宙线天体物理的发展具有重要价值。