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The 13th National Conference on Particle Physics was held from August 16 to 20, 2021. Five young scholars from the Shandong Institute of Advanced Technology (SDIAT) delivered academic reports at the conference, presenting related research advancements in the Alpha Magnetic Spectrometer (AMS) experiment, which attracted widespread attention.

The 13th National Conference on Particle Physics, a quadrennial series hosted by the High Energy Physics Division of the Chinese Physical Society, is the largest and most influential academic conference in China's particle physics community. Organized by Shandong University, the conference was held in an online format due to the recent COVID-19 pandemic in China. Despite this, it attracted over 1,100 researchers from more than 100 universities, institutions, and research institutes nationwide.

Professor Weiwei Xu delivered a report titled "Origin of Cosmic Ray Electrons". Electrons are the most abundant negatively charged particles in cosmic rays. By analyzing 28 million cosmic ray electrons, AMS measured the electron energy spectrum from 0.5 GeV to 1400 GeV, revealing new characteristics of cosmic ray electrons: the spectral index of the electron spectrum undergoes a significant change at 42 GeV, but no high-energy cutoff was observed; the entire energy range of the electron spectrum can be explained by two power-law components. This provides new perspectives for studying the origins of cosmic ray electrons and positrons, as well as searching for traces of dark matter particles.

Assistant Researcher Tong Su delivered a report titled "Measurement of Daily Electron Flux and Analysis of Periodic Features in the AMS Experiment". Based on 175 billion cosmic ray events from the AMS experiment, the team from the Shandong Institute of Advanced Technology (SDIAT) measured the daily flux of cosmic ray electrons and discovered distinct evolutionary patterns over time. The electron flux exhibited periodic characteristics possibly correlated with solar rotation. This is of great significance for understanding the influence of solar activity on cosmic ray flux and serves as fundamental data for establishing solar system radiation prediction and early warning models.

Assistant Researcher Yao Chen delivered a report titled "Progress in Cosmic Ray Isotope Detection with the Alpha Magnetic Spectrometer (AMS)". The AMS Collaboration has published precise measurements of the energy spectra and composition of cosmic ray helium isotope nuclei, fully demonstrating AMS’s superiority in cosmic ray isotope measurements. Currently, AMS has completed the analysis of the energy spectra and composition of cosmic ray lithium and beryllium isotope nuclei, extending the measurement range of their energy spectra to 11 GeV/n with unprecedented precision. This provides critical data for addressing scientific questions such as cosmic ray propagation processes, the origin of cosmic ray lithium nuclei, and cosmic ray age.

Assistant Researcher Zhaomin Wang delivered a report titled "Measurement of Iron Nuclei Energy Spectra in the AMS Experiment". Previously, the AMS experiment discovered through high-precision experimental data that the spectral features of lighter elements (helium, carbon, oxygen) and heavier elements (neon, magnesium, silicon) differ, indicating the existence of two distinct populations of primary cosmic rays in the universe. Unexpectedly, AMS results show that the heaviest iron nuclei instead exhibit the same spectral features as the lighter primary cosmic rays. With high binding energy, iron nuclei are the heaviest nuclei produced by stellar nuclear fusion, making AMS’s precise characterization of iron nuclei a key to unraveling the mystery of cosmic ray origins.

Assistant Researcher Zhaoyi Qu delivered a report titled "Position Calibration of Silicon Microstrip Detectors and Track Reconstruction Algorithms in the Alpha Magnetic Spectrometer (AMS) Experiment". Silicon microstrip detectors serve as the core detectors of the AMS experiment, with track reconstruction and position calibration being fundamental tasks for accurately measuring charged cosmic rays. By employing a track reconstruction algorithm based on a cellular automaton network, the team improved the track reconstruction efficiency by 15%, equivalent to the AMS collecting an additional 27 billion cosmic ray events over 10 years. Additionally, a machine learning-based position calibration algorithm was developed to uncover the relationship between displacement parameters of silicon microstrip detectors and temperature changes, providing the AMS with a real-time online calibration tool.