利用DAMPE在轨数据研究宇宙线质子和氦核的TeV能谱结构

暗物质粒子探测卫星（DAMPE）是中国发射的第一颗空间高能粒子探测卫星，于2015年12月17日成功发射，目前已稳定运行超过四年。暗物质粒子探测卫星具有覆盖能量宽、电荷分辨率高、能量分辨率高等优势，可以实现对TeV以上能段宇宙线核素的成分鉴别和各成分能谱精确测量。本项目计划利用暗物质粒子探测卫星在轨数据对40GeV-200TeV能量区间宇宙线质子和氦核能谱进行分析，这将是首次利用空间实验实现对TeV-PeV宇宙线氦核能谱的直接测量，预期可以观测到氦核存在与质子类似的TeV能谱结构。通过质子和氦核TeV能谱结构的对比分析，确认两者能谱“拐折”能量的关系，有望揭示该能谱结构的物理起源，从而推进银河系宇宙线起源和加速的研究。

The DArk Matter Particle Explorer (DAMPE) is a space-based mission designed as a high energy particle detector for measuring cosmic-rays and gamma-rays in space. It was successfully launched on December 17, 2015, and since then has been in stable data taking for more than four years. The large geometric factor and thick calorimeter enables DAMPE to have very good potential to identify different cosmic-ray components and measure their spectra respectively above TeV energies. We propose to analyze the spectra of cosmic-ray proton and helium from 40GeV to 200 TeV with the flight data of DAMPE experiment. For the first time, the cosmic-ray helium spectrum form TeV to PeV will be directly measured with a space-based calorimeter experiment. It is expected that a TeV spectral structure, similar with what has been observed in the cosmic-ray proton spectrum, will be identified in cosmic-ray helium spectrum. Detailed analysis about the TeV spectral structures of proton and helium may suggest the origin and acceleration of cosmic-rays in the Milky Way.