What is a spallation neutron source? When a medium energy protons hit heavy nucleus (tungsten, mercury and other elements) can lead to unstable and heavy nucleus "evaporate" out of the 20-30 neutrons, such heavy nucleus in all directions from a "crack" and "divergence" out of quite a number of neutrons, greatly improve the efficiency of the neutron production, according to the principle of work device is called a spallation neutron source.
The discovery and application of neutron is one of the most important scientific achievements in the twentieth century, and it is an ideal probe to study material structure and dynamic properties. Neutron scattering technique has been widely used in many fields such as condensed matter physics, biological engineering and material science. The spallation neutron source can let us in the smaller volume can produce high neutron flux, each neutron energy deposition is lower than the reactor 4 to 8 times, per unit volume of four to eight times than fission neutron intensity tall, can be used with low power and high flux reactor or higher average neutron flux.
Mainstream development trend of neutron science device in 21st century, is a high throughput research reactor, another is the spallation neutron source, high flux reactor the source of the strong to achieve 1 ╱ x 1015 cm squared. S, spallation neutron source beam power to achieve mw order of magnitude. Neutron source characteristics and advantages of the two complement each other, become an indispensable tool for scientific research, to provide related the development of extreme technology innovation platform, especially megawatt multi-purpose pulsed spallation neutron source is the current development trend of neutron source in the world.
In March 2018, the Chinese built in Dongguan of Guangdong spallation neutron source to complete the whole project construction tasks, and through the organization process of appraisal and acceptance, of the Chinese academy of sciences, it is the first China is the world's fourth type pulse spallation neutron source, the other three in the United States, Japan, England, respectively. That composed of various kinds of high-grade equipment "jack", since construction began in September 2011, the construction period is 6.5 years, with a total investment of about 2.3 billion yuan, including the core technology of protons can be up to 0.9 times the speed of light. According to the engineering process identification of acceptance of the expert committee evaluation, said: "the Chinese spallation neutron source debugging faster than in other countries the spallation neutron source and target standing highest neutron efficiency reached the international advanced level."
Reference source:
https://baike.baidu.com/item/中国散裂中子源/2018800?fr=aladdin
https://baike.baidu.com/item/散裂中子源/3878179?fr=aladdin
http://tech.sina.com.cn/d/i/2018-03-26/doc-ifysqypu9692032.shtml