Significance of HIAF

Heavy ion accelerator is a device which produces high speed ion beam by artificial method, which includes ion source, accelerator system, electromagnetic guiding and focusing system, beam transmission and distribution system, experimental measuring system, and other supporting facilities. Ions are ionized atoms, and heavy ions refer to those ions with more than four nucleons in the nucleus of the ion center, such as ¹²C ion, ⁵⁶Fe ion, ²³⁸U ion, etc. Heavy ion accelerator is mainly used to generate charged heavy ion beam, also proton beam. It is not only an important tool to explore the basic interaction, the structure of matter and the evolution of the universe, but also a platform to research and develop advanced nuclear technologies related to economic and social development as well as national security.

Entering the 21st century, nuclear science confronts new opportunities for development. The United States and Europe have worked out medium and long term development plans for nuclear physics research, pointing out that the frontier areas of heavy ion nuclear physics research are nuclear structure, nuclear astrophysics, the nature of strongly interaction materials, and new physics beyond the standard model, etc. It relates to several major scientific issues, including the limits of the existence of atomic nuclei and its peculiar structures, the source of heavy elements in the universe, the plasma phase transition of quarks and gluons, the test of fundamental symmetry and so on.

Driven by important scientific and technological goals, sci-tech powers worldwide are building large heavy ion accelerator facilities, such as Facility for Antiproton and Ion Research (FAIR) in Germany, Facility for Rare-isotope Beams (FRIB) in America, and Système de Production d'Ions Radioactifs en Ligne -2 (SPIRAL2) in France, etc. At present, there are Beijing HI-13 Tandem Accelerator and Heavy Ion Research Facility in Lanzhou (HIRFL) in China. HI-13 is a low-energy heavy ion accelerator that has been operating for more than twenty years, while HIRFL can provide stable and radioactive nuclear beams with various kinds and different energies, which presents good conditions and opportunities for Chinese nuclear physics research to advance to the international forefront. However, Chinese heavy ion accelerators are not sound in number, scale, overall performance, and beam time, which is not commensurate with the level of economic development and international status of China. With the new generation of heavy ion accelerator facilities such as FAIR and FRIB being put into operation in the next decades, HIRFL’s overall performance indicators will fall behind obviously and gradually lose its international competitiveness. Therefore, in the face of challenging international environment, China should take control of important position in heavy ion science. By building advanced heavy ion accelerator facilities, enhancing the innovation capacity of nuclear science and Chinese international influence, as well as solving key technologies related to national development, to make a major contribution to the understanding of matter’s structure and exploration of nature’s law, also provide theoretical, method, technical and talent support for the application of nuclear technology. Relying on HIRFL, IMP, as a major influential international heavy ion science research center, engaged in nuclear physics and heavy ion beam applied research. It also developed particle accelerators and nuclear technology research institute. Hence, IMP put forward the construction of major s&t infrastructure ─ “High Intensity Heavy-ion Accelerator Facility” (HIAF).