High Energy Photon Source

High Energy Photon Source. It is a major fourth-generation synchrotron radiation facility located in Beijing, China, representing a significant advancement in the nation's scientific infrastructure. Operated by the Institute of High Energy Physics of the Chinese Academy of Sciences, it is designed to produce extremely bright and coherent X-ray beams for cutting-edge research. The facility positions China at the forefront of materials science, structural biology, and nanotechnology research, joining the ranks of other world-class light sources like the Advanced Photon Source and the European Synchrotron Radiation Facility.

Overview

The primary purpose of this facility is to generate high-intensity, high-energy photon beams for probing the atomic and molecular structure of matter. As a fourth-generation synchrotron, it utilizes a multi-bend achromat lattice design to achieve exceptional beam brightness and coherence, surpassing the capabilities of earlier facilities like the Beijing Synchrotron Radiation Facility. Its construction is a cornerstone project within China's 13th Five-Year Plan for national scientific development, aimed at providing an indispensable tool for researchers across academia and industry. The complex hosts numerous experimental endstations, or beamlines, which serve a diverse international user community from institutions such as Tsinghua University and Peking University.

Technical Specifications

The accelerator complex is based on a 6 GeV electron storage ring with a circumference of 1360.4 meters, making it one of the largest of its kind in Asia. The storage ring employs a hybrid multi-bend achromat lattice, a design also implemented at facilities like the MAX IV Laboratory in Sweden, to achieve an ultralow beam emittance below 60 pm·rad. This design enables the production of X-rays with unprecedented brightness, particularly in the hard X-ray regime. Key supporting systems include a full-energy linear accelerator injector, sophisticated superconducting insertion devices, and advanced beamline optics developed in collaboration with institutions like the Argonne National Laboratory.

Scientific Applications

The intense X-ray beams enable revolutionary experiments across numerous disciplines. In structural biology, researchers can determine the atomic structures of complex proteins and viruses, aiding drug discovery for diseases like COVID-19. In condensed matter physics, scientists probe quantum materials and superconductors to understand novel electronic phenomena. The beams are also critical for advanced industrial applications, such as non-destructive testing of aerospace components at companies like COMAC and probing catalytic processes for clean energy research. Furthermore, fields like archaeology and cultural heritage science utilize the beams for analyzing ancient artifacts without damage.

Development and History

The project was formally proposed by the Institute of High Energy Physics following the successful operation of its predecessor, the Beijing Electron–Positron Collider. Major construction commenced in 2019 after receiving approval from the National Development and Reform Commission. The project timeline accelerated following key technological demonstrations at other Chinese facilities, including the Shanghai Synchrotron Radiation Facility. The engineering phase involved overcoming significant challenges in magnet fabrication and vacuum system design, with critical contributions from partners like the University of Science and Technology of China. The storage ring achieved first stored beam in 2024, marking a pivotal milestone for the project.

Comparison with Other Light Sources

This facility is part of a global wave of fourth-generation synchrotron sources. It operates at a higher energy than the 3 GeV MAX IV Laboratory but at a lower energy than the 7 GeV Advanced Photon Source Upgrade project in the United States. Its design emittance is competitive with other new facilities, such as the Sirius (synchrotron light source) in Brazil and the European Synchrotron Radiation Facility Upgrade Programme in France. While the SPring-8 in Japan offers higher energy (8 GeV) for different scientific cases, this source excels in high brightness and coherence for experiments requiring extreme focusing. Its location in Beijing creates a powerful regional research hub complementary to other major Asian facilities.