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The 37th International Cosmic Ray Conference was held from July 12 to 23, 2021. Multiple scholars from the Shandong Institute of Advanced Technology (SDIAT) delivered academic reports at the conference, presenting cutting-edge research advancements that attracted widespread attention.

The International Cosmic Ray Conference is an international series of conferences guided by the Commission C4 on Cosmic Rays under the International Union of Pure and Applied Physics. Since 1947, it has been held biennially and is the largest and most influential academic conference in the field of particle astrophysics. The 37th conference was hosted by the Deutsches Elektronen-Synchrotron (DESY) in Germany. Despite being held online due to the COVID-19 pandemic, it still attracted over 1,400 researchers from 54 countries and regions worldwide.

Professor Weiwei Xu delivered a special report titled "Measurement Results of the Daily Evolution of Cosmic Ray Electron and Positron Fluxes" on behalf of the AMS Collaboration. Based on 175 billion cosmic ray events from the AMS experiment, the team from the Shandong Institute of Advanced Technology (SDIAT) measured the daily fluxes of cosmic ray electrons and positrons. They found that the electron and positron fluxes exhibit different evolutionary patterns over time, with the electron flux showing periodic characteristics possibly correlated with solar rotation. This is of great significance for understanding the influence of solar activity on cosmic ray intensity and serves as fundamental data for building radiation prediction and early warning models in the solar system.

Assistant Researcher Yao Chen delivered a report titled "Properties of Primary Cosmic Ray Iron Nuclei: AMS Experimental Results"on behalf of the AMS Collaboration. Previously, AMS had discovered through high-precision experimental data that the spectral features of lighter elements (helium, carbon, oxygen) and heavier elements (neon, magnesium, silicon) exhibit differences, indicating the existence of two distinct populations of primary cosmic rays in the universe. Unexpectedly, AMS experimental results showed that the heaviest iron nuclei instead share the same spectral features as the lighter primary cosmic rays. Iron nuclei, with their high binding energy, are the heaviest nuclei produced by stellar nuclear fusion. Thus, AMS provides an accurate understanding of iron nuclei, serving as a key to unraveling the mystery of cosmic ray origins.

Professor Xi Luo delivered a report titled *"Numerical Study of the Impact of Corotating Interaction Regions (CIRs) on the Propagation of Cosmic Ray Protons and Helium Nuclei"*. Corotating interaction regions (CIRs), formed by the interaction between fast and slow solar wind streams, are important drivers of short-period variations in cosmic rays. Combining magnetohydrodynamic (MHD) and cosmic ray numerical models, Luo's team simulated the effects of CIRs on the propagation of cosmic ray protons and helium nuclei. The study found that CIRs reduce cosmic ray intensity, and the flux ratio of protons to helium nuclei is also affected by CIRs.

Xi Luo's team also delivered a report titled "Numerical Simulation of Galactic Cosmic Rays Using AMS Observation Data". Based on a developed time-dependent three-dimensional cosmic ray numerical model, the team reproduced the proton and helium energy spectra observed by AMS. The study revealed that the diffusion coefficient, which significantly impacts cosmic ray modulation, is strongly correlated with solar activity intensity. Additionally, the team interpreted the time-varying flux ratio of protons to helium nuclei from the perspectives of interstellar energy spectra and solar modulation. These findings deepen our understanding of solar modulation of galactic cosmic rays and lay a theoretical foundation for establishing space radiation prediction and early warning systems.