China turns on giant neutrino detector that took a decade to build
(2025/08/29)
- Reference: 1756449011
- News link: https://www.theregister.co.uk/2025/08/29/china_turns_on_giant_neutrino/
- Source link:
More than a decade after construction began, China has commenced operation of what it claims is the world’s most sensitive neutrino detector.
Neutrinos are subatomic particles that have no charge and therefore pass through most matter without leaving any sign of their passing. Physics can’t fully explain neutrinos, so scientists are interested in observing them more often to learn more about how they behave.
The Jiangmen Underground Neutrino Experiment (JUNO) is buried 700 meters under a mountain and features a 20,000-tonne “liquid scintillator detector” that China’s Academy of Science [1]says is “housed at the center of a 44-meter-deep water pool.” There’s also a 35.4-meter-diameter acrylic sphere supported by a 41.1-meter-diameter stainless steel truss. All that stuff is surrounded by more than 45,000 photo-multiplier tubes (PMTs).
[2]
The latter devices are super-sensitive light detectors. A liquid scintillator is a fluid that, when exposed to ionizing radiation, produces light. At JUNO, the liquid is 99.7 percent alkylbenzene, an ingredient found in detergents and refrigerants.
[3]
The acrylic sphere and photomultipliers tube inside JUNO's central detector - Click to enlarge
JUNO’s designers hope that any neutrinos that pass through its giant tank bonk a hydrogen atom and produce just enough light that the detector array of PMTs can record their passing, producing data scientists can use to learn more about the particles.
[4]China is beating the world at scientific research, think tank finds
[5]China sends an AI to its space station, where Taikonauts use it to prep for spacewalk
[6]China to visit Earth’s ‘quasi-moon’ and bring a chunk of it back home
[7]China sends cloud powered by homebrew Loongson CPUs into space
At this point, readers could sensibly ask how JUNO will catch any of these elusive particles.
The answer lies in the facility’s location – a few tens of kilometers away from two nuclear power plants that produce neutrinos.
[8]
The Chinese Academy of Science’s Journal of High Energy Physics [9]says trials of JUNO succeeded, suggesting it will be able to help scientists understand why some neutrinos are heavier than others so we can begin to classify the different types of the particle – a key goal for the facility. The Journal also reports that scientists from Japan, the United States, Europe, India, and South Korea, are either already using JUNO or plan experiments at the facility.
China likes to share some of its scientific achievements. When it [10]retrieved moon rocks , it made sure to show them off and allow some foreign labs to examine them. It looks like Beijing is keen to ensure the world appreciates JUNO’s efforts to help us all appreciate neutrinos. ®
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[1] https://english.cas.cn/newsroom/cas_media/202508/t20250827_1051466.shtml
[2] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=2&c=2aLF6P9EybkErEIMKXX6vdAAAARM&t=ct%3Dns%26unitnum%3D2%26raptor%3Dcondor%26pos%3Dtop%26test%3D0
[3] https://regmedia.co.uk/2025/08/28/supplied_jiangmen_underground_neutrino_experiment.jpg
[4] https://www.theregister.com/2024/08/30/aspi_technology_tracker/
[5] https://www.theregister.com/2025/08/19/china_wukong_ai_space_station/
[6] https://www.theregister.com/2025/05/29/china_tianwen_2_probe_launch/
[7] https://www.theregister.com/2024/11/24/asia_tech_news_in_brief/
[8] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44aLF6P9EybkErEIMKXX6vdAAAARM&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[9] https://ihep.cas.cn/dkxzz/juno/JUNO_dongtai/202508/t20250827_7915624.html
[10] https://www.theregister.com/2024/12/20/chinese_moon_samples_analysis/
[11] https://whitepapers.theregister.com/
Neutrinos are subatomic particles that have no charge and therefore pass through most matter without leaving any sign of their passing. Physics can’t fully explain neutrinos, so scientists are interested in observing them more often to learn more about how they behave.
The Jiangmen Underground Neutrino Experiment (JUNO) is buried 700 meters under a mountain and features a 20,000-tonne “liquid scintillator detector” that China’s Academy of Science [1]says is “housed at the center of a 44-meter-deep water pool.” There’s also a 35.4-meter-diameter acrylic sphere supported by a 41.1-meter-diameter stainless steel truss. All that stuff is surrounded by more than 45,000 photo-multiplier tubes (PMTs).
[2]
The latter devices are super-sensitive light detectors. A liquid scintillator is a fluid that, when exposed to ionizing radiation, produces light. At JUNO, the liquid is 99.7 percent alkylbenzene, an ingredient found in detergents and refrigerants.
[3]
The acrylic sphere and photomultipliers tube inside JUNO's central detector - Click to enlarge
JUNO’s designers hope that any neutrinos that pass through its giant tank bonk a hydrogen atom and produce just enough light that the detector array of PMTs can record their passing, producing data scientists can use to learn more about the particles.
[4]China is beating the world at scientific research, think tank finds
[5]China sends an AI to its space station, where Taikonauts use it to prep for spacewalk
[6]China to visit Earth’s ‘quasi-moon’ and bring a chunk of it back home
[7]China sends cloud powered by homebrew Loongson CPUs into space
At this point, readers could sensibly ask how JUNO will catch any of these elusive particles.
The answer lies in the facility’s location – a few tens of kilometers away from two nuclear power plants that produce neutrinos.
[8]
The Chinese Academy of Science’s Journal of High Energy Physics [9]says trials of JUNO succeeded, suggesting it will be able to help scientists understand why some neutrinos are heavier than others so we can begin to classify the different types of the particle – a key goal for the facility. The Journal also reports that scientists from Japan, the United States, Europe, India, and South Korea, are either already using JUNO or plan experiments at the facility.
China likes to share some of its scientific achievements. When it [10]retrieved moon rocks , it made sure to show them off and allow some foreign labs to examine them. It looks like Beijing is keen to ensure the world appreciates JUNO’s efforts to help us all appreciate neutrinos. ®
Get our [11]Tech Resources
[1] https://english.cas.cn/newsroom/cas_media/202508/t20250827_1051466.shtml
[2] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=2&c=2aLF6P9EybkErEIMKXX6vdAAAARM&t=ct%3Dns%26unitnum%3D2%26raptor%3Dcondor%26pos%3Dtop%26test%3D0
[3] https://regmedia.co.uk/2025/08/28/supplied_jiangmen_underground_neutrino_experiment.jpg
[4] https://www.theregister.com/2024/08/30/aspi_technology_tracker/
[5] https://www.theregister.com/2025/08/19/china_wukong_ai_space_station/
[6] https://www.theregister.com/2025/05/29/china_tianwen_2_probe_launch/
[7] https://www.theregister.com/2024/11/24/asia_tech_news_in_brief/
[8] https://pubads.g.doubleclick.net/gampad/jump?co=1&iu=/6978/reg_offbeat/science&sz=300x50%7C300x100%7C300x250%7C300x251%7C300x252%7C300x600%7C300x601&tile=4&c=44aLF6P9EybkErEIMKXX6vdAAAARM&t=ct%3Dns%26unitnum%3D4%26raptor%3Dfalcon%26pos%3Dmid%26test%3D0
[9] https://ihep.cas.cn/dkxzz/juno/JUNO_dongtai/202508/t20250827_7915624.html
[10] https://www.theregister.com/2024/12/20/chinese_moon_samples_analysis/
[11] https://whitepapers.theregister.com/