In Jiangmen, go deep into the underground 700 meters to explore the mystery of the universe 丨 large project and large engine

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【Squat】 Jiangmen

[Major Project] Jiangmen Zhongmei Laboratory

[Portrait] particle physics is one of the most important cutting -edge sciences at present. The construction of the Jiangmen neutron laboratory will establish an internationally leading position in the field of China's neutron research, and provide important support for the construction of the comprehensive national science center of the Guangdong -Hong Kong -Macao Greater Bay Area.

The project team of the Jiangmen Zhongwei Lab has completed a number of technical research, achieving a number of "world's best." The picture shows the detector center of the experimental equipment in the construction. Jiangmen Zhongmei Laboratory Photo Conferry

Every second, about 100 billion universe "hidden people" through the size of the size of our body's nails, but we can not perceive their existence at all. Is it magical?

This "hidden person" is the neutrine of one of the most basic particles of the material world. It is ubiquitous in the universe, very small and light, and one -million less than electrons. It is very difficult to detect the speed of light and detect. It is called "ghost particles". But neutrinos played a very important role in the origin, evolution of our entire universe, and the source of the energy of the sun and the earth.

In the past hundreds of years, neutrinos research has been a popular discipline in the physics world. Since the discovery of neutrinos in the 1930s, the Nobel Prize has been awarded in the field of neutrinos.

In the depth of 700 meters underground in Jinji Town, Kaiping City, Jiangmen, a series of advanced scientific equipment in the world's largest experimental cave is in the world. The purpose is to capture and measure the "ghost particles" -mochri. This is the Jiangmen neutron laboratory. The Jiangmen Microcons Laboratory is a large scientific device jointly constructed by the Chinese Academy of Sciences and Guangdong Province. It is expected that after completion in 2024, it will become one of the center of international neutron research.

This year's work report of the Guangdong Provincial Government proposes to strengthen strategic technology. These include the construction of Jiangmen Zhongmei Laboratory, the construction of the second phase of the Sanzhongzi Source, and the construction of a world -class and major scientific and technological infrastructure group with concentrated disciplines and regional agglomeration. "The construction of the Jiangmen neutralized laboratory will establish an internationally leading position in the field of China's neutron research." Said Li Xiaonan, a researcher at the Institute of High Energy Physics and Kaiping Zhongmei Research Center, said.

Keep the key technical problem of "world -class" key technical problems

Centered on the Yangjiang Nuclear Power Station and Taishan Nuclear Power Station, and draw a circle with a radius of 53 kilometers respectively. The intersection point on the land is the area where the Jiangmen neutron laboratory is located.

Why is it here? Li Xiaonan introduced: "We inspected many places, and finally I was fortunate to find this place in Kaiping."

Li Xiaonan told the reporter of "Southern" that on the one hand, a large number of neutrinos will be generated by nuclear reactor power generation, so the laboratory is generally located near the nuclear power plant. Studies have shown that the neutron oscillation effect is the most obvious and easier to capture at 53 kilometers away from the reactor, and Jinji Town is located 53 kilometers each of Yangjiang and Taishan Nuclear Power Station. At present, the effective reactor group of Yangjiang and Taishan Nuclear Power Station ranks first in the world. The larger the reactor power, the more neutrinos released.

On the other hand, there are a large number of cosmic rays in the daily environment. If no shielding is added, the signals generated in the detector will be hundreds of millions of times more than a rare neutrinous signal. Therefore, the neutron detector needs to be placed in a deep underground and use rocks to block the cosmic rays. "In addition, the span of the underground cave reaches 50 meters, and it needs to be supported by the rock body's own structure. This requires the rock body to be a very hard granite, and the stone mountain of Jinji Town just meets all conditions." Li Xiaonan said.

When I walked into the Jiangmen Zhongmei Laboratory, I saw the mountains surrounded by mountains, and the surrounding environment was extremely quiet. At present, supporting infrastructure projects such as ground office buildings, assembly halls, dormitory buildings, cafeterias, and underground experimental halls, experimental pools and affiliated cave excavation construction projects have been basically completed at the end of 2021.

Take a cable car, quickly drop in a closed dark environment for more than 10 minutes, and come to about 700 meters underground. Out of the cable car, walking hundreds of meters along the potholes, turning a few curves, a huge circular cave with a horizontal span of about 50 meters and a tens of meters high in the dome appeared in front of the reporter. In the cave, an equally huge spherical stainless steel structure has been completed.

According to Li Xiaonan, the experimental equipment is called a central detector, mainly in an organic glass ball with a diameter of 35.4 meters. 20,000 tons of liquid flashes, the outer wall is covered with tens of thousands of optoelectricity pipes, and the neutron is " The flashing light generated during capturing ". The entire center detector is soaked in about 35,000 tons of high -pure water pools. At present, the installation of organic glass installation of the experimental equipment and the stainless steel mesh shell have been installed, and the central detector organic glass is installed.

"The entire experiment has put forward extremely high requirements for liquid flashing body, high -pure water transparency, etc., and also requires high quality and transparency of organic glass balls." Li Xiaonan explained The photon produced by the micro -collision liquid flashing is at least 20 meters in the fluid, which requires a high degree of light transmission.

在建设过程中，江门中微子实验室项目团队不断克服困难，攻克了探测器研制的诸多关键技术难题，实现了多个“世界之最”：世界最大的有机玻璃容器（直径35.4米）、 The world's highest photoelectric boring pipe (domestic micro -channel plate -type photoelectric pipe detection efficiency is> 30%), and the world's most transparent liquid flashing body (attenuation length> 20 meters). In the office of the office building of the Jiangmen Zhongjing, the "Southern" magazine reporter saw a "huge light bulb". According to Li Xiaonan, this "bulb" is a 20 -inch micro -channel plate -type photoelectric pipe independently developed by China. About 18,000 20 -inch photoelectric pipes.

The challenges in infrastructure are equally huge. To excavate an underground cave of 50 meters in 700 meters underground, there must be no support for a pillar, which has almost no precedent in China. Over the past few years, construction workers overcome difficulties such as rushing water and faults, and finally completed infrastructure work in December 2021.

Establish an international leading position in the field of China's neutron research

The research of neutral microons is a hot spot for international particle physics research. In 1998, the Japanese Super Kamagang Experiment and the 2001 Canadian Sno experiment proved the phenomenon of oscillation of neutrinos, indirectly proved that neutrinos had a small quality and had a significant impact on particle physics, celestial physics and cosmology.

There are three types of medium microons. In principle, the three neutrinos are oscillation of each other. There should be three modes in two or two combinations. However, the third medium micro -oscillating mode has not been discovered.

Li Xiaonan introduced that my country's neutrinos' research began in 2003, which began in 2003. This experiment led by the Chinese has successfully discovered the third oscillation model of neutrinos, becoming a milestone in my country's neutrinos research. The experimental results won the 2016 National Natural Science Award of the National Natural Science Award.

The Daya Bay Experiment has completed the historical mission of accurately measured the third oscillating mode of the microphone, making it possible to measure the quality order and CP phase angle of the microphone in the current stage. The construction of the medium micro -laboratory was put on the agenda. In 2013, the Chinese Academy of Sciences established a strategic pilot technology special project to build Jiangmen neutrinos in Guangdong Province.

Judging from the weight of the liquid flashing body, the size of the Jiangmen neutron laboratory has reached 1,000 times that of the Da Ya Bay neutral laboratory. After completion, it will become the world's largest and most advanced liquid flashing neutron laboratory.

In the office building of the Jiangmen Neutonal Laboratory, a reporter from the "Southern" magazine saw that the wall clearly marked "the next challenge: the quality of the quality of the medium microconut".

"If the Daya Bay Lab is the beginning of the research of neutrinos research, then the Jiangmen neutron laboratory is a leap -up stage." Li Xiaonan said that the Daya Bay experiment proved that the neutrinos are quality. The quality order of the three neutrinos is the most critical and most needed question for the current research of neutrinos, which plays an important role in studying the origin of the universe.

"The construction of the Jiangmen neutron laboratory will establish an internationally leading position in the field of China's neutron research." Li Xiaonan said.

Li Xiaonan told the reporter of "Southern" that in the next step, the laboratory will continue to speed up the installation and testing of the central detector, and strive to complete the installation of the experimental device as planned. At the same time, the laboratory will focus on the favorable opportunities of the middle and micro -laboratory operations, make a solid plan for the Popular Popularization Museum, and make every effort to build the popular science museum into innovative popular science popularization in science research, science popularization, research, business, and tourism. base.

Strike the construction of the Comprehensive National Science Center of the Guangdong -Hong Kong -Macao Greater Bay Area

This year's work report of the Guangdong Provincial Government proposed that "strengthening strategic technology forces" and "building a world -class major scientific and technological infrastructure group with concentrated disciplines and regional agglomerations". The report also proposes that the implementation of basic and application foundation for ten years of "Zhuoyue" plan, and puts more than 3 provincial -level scientific and technological innovation strategic special funds for basic research.

It is understood that the total investment in Jiangmen Zhongmou Laboratory Infrastructure Supporting Project is about 730 million yuan, and the total investment of experimental equipment installation is about 2 billion yuan. As one of the five major national scientific devices deployed and constructed by the Chinese Academy of Sciences in Guangdong, and one of the five major scientific and technological infrastructures of Guangdong's "Fourteenth Five -Year Plan" planned in the country, Jiangmen neutron laboratory will be comprehensive for the Guangdong -Hong Kong -Macao Greater Bay Area The construction of the National Science Center provides important support.

According to Li Xiaonan, Jiangmen Zhongwei Laboratory has cooperated with many Guangdong universities such as Sun Yat -sen University, Dongguan Institute of Technology, and Wuyi University. "The large scientific device is very wide. For example, we have set up a small liquid flash detector near the nuclear power plant, which is responsible for Wuyi University. Through similar methods, we can cultivate related basic research talents for Guangdong's universities."

The relevant person in charge of the Jiangmen Science and Technology Bureau revealed that in order to further expand the cutting -edge science science science science function of the China Micro -Treasure Experimental Project, Jiangmen City is currently cooperating with Jiangmen Zhongmei Laboratory to actively build the China Micro -Small Science Press and create a youth research base. The National Popular Science Education Base, relying on the popular science museum to build a small town of popular science.

Responsible for this article 丨 Guo Fang

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