标题： 暗物质粒子探测器观测宇宙射线电子和正电子的Forbush减少现象 显示英文标题

标题： Observations of Forbush Decreases of cosmic ray electrons and positrons with the Dark Matter Particle Explorer

摘要： 地磁暴（FD）表示与日冕物质抛射（CME）或来自极区高速流相关的带电粒子强度的快速下降。 它主要通过基于地面的中子监测器网络进行研究，这些网络间接测量宇宙射线所有种类的综合强度，通过计数大气原子与宇宙射线相互作用产生的次级中子。 基于空间的实验可以分辨出粒子的种类，但能量范围受到相对较小的接受度限制，除非是最丰富的粒子如质子和氦核。 因此，宇宙射线电子和正电子的地磁暴效应仅由PAMELA实验在低能范围（$<5$ GeV）内进行了研究，且统计量有限。 本文研究了2017年9月发生的地磁暴事件，使用的是由中国暗物质粒子探测卫星记录的电子和正电子数据。 给出了从2 GeV到20 GeV的地磁暴随时间分辨率（6小时）的变化过程。 我们在宇宙射线强度的时间剖面中观察到两次太阳高能粒子事件，其中较早且较弱的一次未在中子监测数据中显示。 此外，电子和正电子流量的振幅和恢复时间表现出明显的能量依赖性，这对研究日冕物质抛射引起的星际环境扰动具有重要意义。 显示英文摘要

摘要： The Forbush Decrease (FD) represents the rapid decrease of the intensities of charged particles accompanied with the coronal mass ejections (CMEs) or high-speed streams from coronal holes. It has been mainly explored with ground-based neutron monitors network which indirectly measure the integrated intensities of all species of cosmic rays by counting secondary neutrons produced from interaction between atmosphere atoms and cosmic rays. The space-based experiments can resolve the species of particles but the energy ranges are limited by the relative small acceptances except for the most abundant particles like protons and helium. Therefore, the FD of cosmic ray electrons and positrons have just been investigated by the PAMELA experiment in the low energy range ($<5$ GeV) with limited statistics. In this paper, we study the FD event occurred in September, 2017, with the electron and positron data recorded by the Dark Matter Particle Explorer. The evolution of the FDs from 2 GeV to 20 GeV with a time resolution of 6 hours are given. We observe two solar energetic particle events in the time profile of the intensity of cosmic rays, the earlier and weak one has not been shown in the neutron monitor data. Furthermore, both the amplitude and recovery time of fluxes of electrons and positrons show clear energy-dependence, which is important in probing the disturbances of the interplanetary environment by the coronal mass ejections.