New Year greetings from the world's deepest underground laboratory, please receive!

◎ Science and Technology Daily reporter Zhang Galen

"Post-90s" Jing Mingkun has been working in the Jinping Underground Laboratory in China for nearly seven years.

After graduating from Chengdu University of Technology, he plunged into the laboratory in this deep mountain and became a scientific research assistant for the Jinping Laboratory project of Tsinghua University. This is a job that Jing Mingkun "can't think of" when he was in college - in the country's major scientific and technological infrastructure, together with researchers, looking for dark matter.

To find dark matter, it is demanding. We live in the background sound of cosmic rays, where different particles make different sounds. But dark matter, hardly silent.

China Jinping Underground Laboratory provides a quiet enough environment. Located in the middle of the JinpingShan Traffic Tunnel in Liangshan Yi Autonomous Prefecture, Sichuan, it is currently the underground laboratory with the lowest cosmic ray flux in the world and the deepest underground laboratory in the world.

Here, the researchers try to block out all known noise, and create ears that are sensitive enough to hear the whispers of dark matter.

Jing Mingkun's daily work is to detect the radiation background of various samples. Each material actually comes with its own radiation, that is, its own noise. In recent times, the workload has been quite large. China's Jinping underground laboratory is "expanding", and all kinds of building materials continue to be delivered to Jing Mingkun' hands: cement, steel bars, bricks... Each one must pass the test before it can be officially put into laboratory construction.

In December, Jing Mingkun measured 110 materials, each of which took about 3 hours, and he spent more than 10 hours a day in the laboratory.

Jing Mingkun is already familiar with the testing process: get the sample material, stir it to a uniform level, put it in the sample box, fill it with compaction, and put it into the instrument to measure the basic data. When the instrument is working, Jing Mingkun drafts a report on the computer; after that, the key information in the energy spectrum given by the instrument is extracted, the simulation calculation is carried out, and the final value is obtained; the value is compared with the reference value to determine whether the material is qualified.

In 2021, Jing Mingkun lived in the mountains for 10 months. Life is simple enough, basically a dormitory, a canteen, a laboratory three points and a line, he likes this state.

The association with Jinping stemmed from an "escort".

In April 2015, Jing Mingkun was about to graduate, and he had found a job in his hometown of Mianyang, Sichuan Province. At that time, the classmates saw the recruitment notice of the Underground Laboratory of Jinping in China and called him to accompany him to "turn around". "I haven't been to Liangshan, and I didn't have anything to do before graduation, so I went and became a tourist." Jing Mingkun and his classmates first went to Xichang, then took a car for more than two hours to "visit" Jinping's underground laboratory.

After that, like all the stories related to the "accompanying examination", the classmates did not choose Jinping, but Jing Mingkun decided to stay.

This job obviously did not meet Jing Mingkun's needs of being "close to home". From Xichang to Mianyang, if you take the train, it will take more than ten hours.

But Jing Mingkun felt that it was suitable for him. His undergraduate science is nuclear engineering and technology, professional counterpart; the content of his work is also "tall", his parents said, this is to contribute to the country. Jing Mingkun does not like to deal with too many people and prefers to be alone. In Jinping, his planet, which likes to rotate alone, has found a vast universe that can accommodate him.

In fact, there are not many people working in the underground laboratory of China Jinping. There are researchers, field workers, engineering managers and administrative teams... At the beginning of the construction of the laboratory, it was a cooperation project between Tsinghua University and Yalong River Basin Hydropower Development Co., Ltd., and in 2019, the construction of major national scientific and technological infrastructure projects was officially launched, and the China Jinping Underground Laboratory became a national platform. Now, Yalong River Basin Hydropower Development Co., Ltd. has established the Jinping Underground Laboratory Management Bureau, and more people have provided all-round guarantees for the smooth operation of scientific research projects.

However, it is easy to get along with everyone, here, people deal with each other, there are not so many twists and turns, which makes Jing Mingkun feel relaxed.

In the past, Jing Mingkun didn't even know how to screw; but when it came to the laboratory, many equipment had to be installed and adjusted by himself. He got started quickly and learned to be on his own. "Now, I basically use the tools you can see in the repair shop and the processing workshop." The daily use of electric drills, wrenches, hammers, pliers, screwdrivers, for him, is no longer a problem.

China's Jinping Underground Laboratory has produced some international cutting-edge research results, and the dark matter detection team is gradually narrowing the possible hiding range of dark matter. "I sometimes think that behind those great achievements, there is also a small part of my strength. All the materials, without my testing, there is no way to enter, I feel that I am a more important part. Jing Mingkun said with a smile, "It's a bit of an exaggeration to say this, but you have to be sure of your own existence." ”

After all, in the face of the grand task of exploring the frontiers of the universe, human beings will inevitably feel small.

Now, China Jinping Underground Laboratory is undergoing a second phase of expansion, and the available space will increase from the previous 4,000 cubic meters to 300,000 cubic meters. Researchers look forward to it becoming a global center for deep-earth scientific research in the future, when different teams, with their own puzzles to be solved, will gather here.

"There will be more tasks, more complex jobs later on. I also want to improve myself and face more challenges. "The Year of the Tiger is coming, Jing Mingkun does not have any special wishes, he wants to be down-to-earth and do a good job."

During the Spring Festival, staff will still stay behind in the underground laboratory buried at a depth of 2400 meters. Here, they listen to the footsteps of the Year of the Tiger and the sounds of everything in the universe.

Source: Science and Technology Daily

Editor: Zhang Qiqi

Review: Yue Liang

Final Judgement: Wang Yu