Located in Huizhou, in South China’s Guangdong Province, the High Intensity Heavy-ion Accelerator Facility (HIAF) completed construction and passed technical review on 21 July.
Designed and developed by the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences (CAS), HIAF is a multifunctional accelerator with leading beam parameters for heavy-ion physics and applications.
The project was proposed by IMP in 2009 and broke ground in at the end of 2018. After seven years of construction, the facility completed its first comprehensive beam commissioning in October 2025.
HIAF is designed to generate the world’s most intense pulsed heavy-ion beams
Heavy-ion accelerators act as an enhanced microscope for scientific exploration around the evolution of the universe, particle physics and nuclear science.
HIAF spans 80 acres and includes a two-kilometre beamline situated 13 metres underground. It is reportedly the world’s first advanced heavy-ion research facility to integrate a superconducting linear accelerator with a fast-cycling synchrotron and is designed to generate the world’s most intense pulsed heavy-ion beams, with energies ranging from MeV/u to GeV/u.
“High intensity is the core indicator for a next-generation ion accelerator. It means that the number of ions accelerated per pulse is substantially increased,” said Prof. Yang Jiancheng, deputy director of IMP and chief engineer of the HIAF project. “Achieving this ultra-high intensity presents significant technical challenges, with the research and development of key technologies spanning over a decade.”
Other innovations include utra-fast ramping power supplies capable of changing current by thousands of amperes in just 100 milliseconds (corresponding to a magnetic field ramping rate of 12 T/s), and a high-precision radiofrequency system delivering an electric field strength of approximately 35 kV/m.
The facility also has an ultra-clean environment within a thin-walled, titanium alloy-lined chamber, achieving a vacuum pressure comparable to that on the Moon.
The facility is already exceeding expectations
These technological advances have enabled HIAF to demonstrate beam performance exceeding its design specifications. Notably, the facility achieved an intensity of 2.5 × 10¹¹ particles per pulse for oxygen ion beams and 3.2 × 10¹⁰ particles per pulse for bismuth ions, setting new world records for beam intensity among similar facilities. The oxygen ion beam reached a maximum energy of 4.25 GeV.
HIAF is one of the few accelerators worldwide capable of accelerating a wide range of ion species, from hydrogen to uranium, and producing thousands of species of unstable atomic nuclei.
It focuses on three major scientific goals: exploring the limits of nuclear existence, unravelling nuclear astrophysics processes, and advancing the interdisciplinary applications of heavy ions.
The facility is equipped with six experimental terminals, including the Spectrometer Ring, the Gas-filled Recoil Achromatic Solenoid Spectrometer, and the High-Rigidity Radioactive Ion Beam Line.
HIAF will be open to international scientific users
During commissioning experiments, researchers achieved a mass accuracy for the short-lived nuclide Au-202 that is twice as precise as the previous world record. They also observed two new isotopes, highlighting the facility’s integrated strengths in high intensity, high energy, and high precision.
“HIAF is set to become a globally significant heavy-ion research hub. Scientists from universities, research institutes, and industries around the world are welcome to collaborate and conduct experiments here,” said Yang.