New weapon against cancer! China Spallation Neutron Source: making the microscopic world “visible”

From "a piece of paper plan" to the creation of a "national treasure", my country's first pulsed spallation neutron source, the China Spallation Neutron Source, was born in Dongguan, Guangdong. Liang Tianjiao, deputy director of the Spallation Neutron Source Science Center, led the team to achieve a number of zero breakthroughs in high-power target stations, promote the open operation and scientific application of spectrometers, and participate in the design and development of new anti-cancer "weapons" based on the technology developed by the project... At present, the second phase of the China Spallation Neutron Source project will start construction in the second half of this year.

China's Spallation Neutron Source has become the core scientific facility of the Greater Bay Area (Photo provided by Songhu Xuan)

It is reported that the source of neutron scattering applications lies in the neutron performance of the target station, which directly determines the production efficiency and quality of the "neutron factory". Liang Tianjiao introduced the initial construction of the China Spallation Neutron Source (CSNS) and mentioned that compared with the proton accelerators and neutron spectrometers that my country has already accumulated, designing and building a good target station has become a major challenge for the CSNS project.

The construction of CSNS has the dual attributes of scientific research and engineering. How to ensure the physical advancement? How to ensure the feasibility of the project? The design plan of the target station has undergone many major adjustments. Each adjustment requires a lot of time and energy to recalculate and design, and comprehensively consider factors such as physical performance, technical feasibility, and maintainability. From the initial plan of horizontal maintenance of fixed targets plus methane moderators, to the plan of rotating targets plus liquid hydrogen moderators, and then to the plan of separate maintenance of fixed targets plus liquid hydrogen moderators, the compactly coupled high neutron efficiency target station plan was finally determined. Through the physical and engineering design of compact coupling of target-moderator-reflector, the high neutron efficiency of the target station is guaranteed.

In September 2011, the construction of CSNS started. This is the first large-scale scientific project built off-site in my country. At 10:56:18 on August 28, 2017, the spallation neutron source successfully hit the target and produced the first beam of neutrons.

CSNS was officially opened in 2018. It not only meets the needs of cutting-edge research methods for cutting-edge basic research and key technology research, but is also widely used in related research and development that is closely related to the lives of many people. The spallation neutron source is like a "super microscope" that can use neutron scattering to detect the microscopic structure and dynamics of matter. In order to efficiently and safely mine and utilize combustible ice, neutron scattering can be used to study the formation mechanism and stability conditions of combustible gas methane hydrate; in the field of engineering machinery, neutron scattering can be applied to the study of residual stress and metal fatigue of large engineering components; in the medical and health industry, this technology can be used to see the changes in proteins at different time and space scales...

Among them, small-angle neutron scattering instruments and micro-angle neutron scattering instruments detect the microscopic structure of the material at the nanometer to micrometer scale. Liang Tianjiao gave an example: "It can also be used to study how to adjust the ingredients of ice cream to make it more delicious." He also said that due to its advantages in studying energy materials and soft matter containing light elements such as hydrogen and lithium, neutron spectrometers have also become a "weapon" for studying lithium batteries.

Relying on the technology developed by the spallation neutron source project, the accelerator-based boron neutron capture therapy device plans to conduct human clinical trials in Dongguan next year. Boron Neutron Capture Therapy (hereinafter referred to as BNCT) will bring hope to cancer patients. The treatment principle of this device is that boron drugs are targeted and enriched in cancer cells in tumor patients, and neutrons are injected to "detonate boron drugs" and accurately "strike" cancer cells. "For brain gliomas, melanomas, and recurrent tumors of the head and neck, BNCT is an effective treatment method, and attempts have been made to treat organ tumors such as lung cancer, liver cancer, and pancreatic cancer." Liang Tianjiao explained. He also mentioned that it is necessary to increase investment in scientific research, strengthen international cooperation, and accelerate the process of technological innovation and industrialization. He hopes to transform this scientific and technological achievement into practical application as soon as possible to benefit cancer patients.

Produced by Guangdong Science and Technology Newspaper Media Center

Gatekeeper | Liang Tianjiao, Deputy Director of the Spallation Neutron Source Science Center

Editor | Li Wanxin

Review | Liu Xiaoyong