China's first high-energy synchrotron radiation facility to be lit in 2024: chief engineer

As the last magnet of China's High Energy Photon Source (HEPS) was successfully installed in the Huairou Science City in Beijing on December 11, 2023, the first step of the HEPS storage ring installation was officially completed. The HEPS, after completion, will stand as one of the brightest synchrotron radiation (SR) sources in the world and the first high-energy synchrotron radiation facility in China.

Pan Weimin, the chief manager of the HEPS project, along with the audience, toured the HEPS project via video footage at a New Year's Eve event hosted by the Beijing Association for Science and Technology, demonstrating an important development in China's high-tech fields.

"The HEPS, once completed, will become one of the brightest synchrotron radiation light sources in the world. This will underline that China has become one of the frontrunners in the field of X-ray-based forms of research," Pan told the Global Times.

The HEPS is designed with the capacity to emit X-ray beams that are a trillion times brighter than those of the sun. From an aerial view, the HEPS consists of three main buildings, with an overall shape resembling a magnifying glass, symbolizing "a tool for exploring the microscopic world."

Pan introduced that the HEPS has the characteristics of high energy, high brightness, and high repetition frequency, which means scientists can observe the deep internal structures of microscopic substances more clearly and characterize the microscopic structures in multiple dimensions, real-time, and in-situ.

The photon source is scheduled to accelerate the storage ring in July 2024, and emit its first SR light by the end of the year. The quality of the SR X-ray will be continuously improved to reach its design specifications from then on, according to Pan.

Once completed, HEPS will be one of the world's top five high-energy SR light sources and one of the few fourth-generation SR light sources. "This would greatly enhance China's scientific and technological status and promote technological innovation in fields related to people's livelihoods such as life sciences and energy," Pan said.

At the same time, as an open user facility, the HEPS will also attract more scientists from all over the world to conduct SR-based research projects, and pave the way for ground-breaking research, Pan noted.

The brighter light source requires more advanced technologies. The HEPS is mainly comprised of an electron accelerator complex and beamlines. The electron accelerator complex includes a linear accelerator, booster, and storage ring. Among them, the storage ring is the core part of the light source, producing a bright SR beam and requiring greater advancements in technologies.

With a circumference of approximately 1,360 meters, the storage ring contains more than 1,700 high-precision magnets and other important accelerator elements. It is required that the alignment errors of most of these elements must be controlled within 50 micrometers, which is less than the diameter of the human hair over such a large scale, according to Pan.

More than 500 researchers have been involved in the HEPS project, which consists of multiple disciplines such as magnets, vacuum, power supply, mechanics, and X-ray optics and detection. How to integrate various technologies and let talents from various disciplines collaborate with each other are the keys to realizing a large-scale scientific project such as HEPS, Pan noted.

"It is the golden age of science. Participating in the construction of such a large-scale scientific facility is not only an honor for a scientist, but also an opportunity to exercise, improve, and showcase oneself, especially for young scientists," he said.