分类： 物理学 >> 核物理学 提交时间： 2023-09-11
Guo, Dong
Haoqian Xyu
DongDong Qi
HeXiang Wang
Lei Zhang
Zhengyang Sun
Zhi Qin
Botan Wang
Yingjie Zhou
Zekun Wang
Yuansheng Yang
Yuhao Qin
Xianglun Wei
Herun Yang
Yuhong Yu
Lei Zhao
Zhigang Xiao
摘要： A trigger system has been designed and implemented for the HIRFL-CSR external target experiment (CEE), the spectrometer for studying nuclear matter properties with heavy ion collisions in the GeV energy region. The system adopts master-slave structure and serial data transmission mode using optical fiber to deal with different types of detectors and long-distance signal transmission. The trigger logic can be accessed based on command register and controlled by a remote computer. The overall field programmable gate array (FPGA) logic can be flexibly reconfigured online to match the physical requirements of the experiment. The trigger system has been tested in beam experiment. It is demonstrated that the trigger system functions correctly and meets the physical requirements of CEE.
分类： 天文学 >> 天文学 提交时间： 2023-02-19
Shuai Fu
Zheyi Ding
Yongjie Zhang
Xiaoping Zhang
Cunhui Li
Gang Li
Shuwen Tang
Haiyan Zhang
Yi Xu
Yuming Wang
Jingnan Guo
Lingling Zhao
Yi Wang
Xiangyu Hu
Pengwei Luo
Zhiyu Sun
Yuhong Yu
Lianghai Xie
摘要： Solar energetic particles (SEPs) associated with flares and/or coronal mass ejection (CME)-driven shocks can impose acute radiation hazards to space explorations. To measure energetic particles in near-Mars space, the Mars Energetic Particle Analyzer (MEPA) instrument onboard China's Tianwen-1 (TW-1) mission was designed. Here, we report the first MEPA measurements of the widespread SEP event occurring on 29 November 2020 when TW-1 was in transit to Mars. This event occurred when TW-1 and Earth were magnetically well connected, known as the Hohmann-Parker effect, thus offering a rare opportunity to understand the underlying particle acceleration and transport process. Measurements from TW-1 and near-Earth spacecraft show similar double-power-law spectra and a radial dependence of the SEP peak intensities. Moreover, the decay phases of the time-intensity profiles at different locations clearly show the reservoir effect. We conclude that the double-power-law spectrum is likely generated at the acceleration site, and that a small but finite cross-field diffusion is crucial to understand the formation of the SEP reservoir phenomenon. These results provide insight into particle acceleration and transport associated with CME-driven shocks, which may contribute to the improvement of relevant physical models.
点击量
待评议
点击量
下载量
评论
