In the coming months a giant sphere 700 meters (2,300 feet) underground will be sealed into a 12-story cylindrical pool of water with thousands of light-detecting tubes for an experiment that will shed new light on elusive subatomic particles called neutrinos.
After years of construction, the $300 million Jiangmen Underground Neutrino Observatory (Juno) in China’s southern Guangdong province may soon produce data on neutrinos, the product of nuclear reactions, to help solve one of the biggest mysteries in particle physics. Will start collecting.
Every second, trillions of extremely small neutrinos pass through matter, including the human body. In mid-flight, a neutrino, of which there are three known varieties, may transform into other types. Determining which types are lightest and heaviest will provide clues to subatomic processes during the early days of the universe and explain why matter is the way it is.
To this end, Chinese physicists and collaborating scientists from around the world will spend six years analyzing data on neutrinos emitted by two nearby Guangdong nuclear power plants.
Juno will also be able to observe neutrinos from the Sun, gaining a real-time view of solar processes. It can also study neutrinos released from the radioactive decay of uranium and thorium in Earth to better understand the mantle convection that drives tectonic plates.
View of a cable car that carries workers, scientists and visitors through a 1,266-metre-long sloping tunnel 700 meters underground.
Due to become operational in the late 2025, Juno will overtake the much larger Deep Underground Neutrino Experiment (DUNE) under construction in the United States. DUNE, supported by the Long-Baseline Neutrino Facility (LBNF) under Fermilab, the top particle physics laboratory of the US Department of Energy (DOE), will come online around 2030.
The race to understand neutrinos and advance the study of particle physics, which has transformed medical imaging technologies and developed new energy sources, accelerated when DOE abruptly cut funding to US institutions collaborating on Juno. Did it. Instead it focused on the production of DUNE, which has since been plagued with delays and budget overruns, with costs exceeding $3 billion.
“China supported Fermilab’s LBNF at the time, but later cooperation could not continue,” Wang Yifang, Juno’s chief scientist and project manager, told Reuters during a recent government-backed media tour of the facility.
Chinese physicists and collaborating scientists from around the world will analyze data on neutrinos.
“Around 2018-2019, the US DOE told all national laboratories not to cooperate with China, so Fermilab was forced to stop working with us.”
The DOE, the largest US funding agency for particle physics, did not respond to a Reuters request for comment.
China-America tensions have increased rapidly in the last decade. A trade war broke out during the Trump administration and President Joe Biden later banned the sale of advanced technology to China.
In August, the bilateral science and technology cooperation agreement signed in 1979 expired, potentially prompting more scientists to seek alternative partners, creating duplication of research and missing out on collaborations that might otherwise have yielded beneficial discoveries. .
In the 2010s, the countries jointly built a nuclear reactor that could use low-enriched uranium, reducing the risk of any fuel becoming a weapon.
China’s Foreign Ministry said Beijing was “in communication” with Washington about the lapsed science agreement. The US State Department did not comment.
sole US ally
Institutions collaborating on Juno come from places including France, Germany, Italy, Russia and the US, and even self-ruled Taiwan, which China claims as part of its territory.
Neutrino observatories are also being built at other locations.
“The one in the US will be six years behind us. And the one in France and Japan will be two or three years behind us. So we believe we can get the results of the mass hierarchy (of neutrinos) ” Ahead of everyone else,” Wang said.
So far, neutrino applications in real life remain a distant possibility. Some scientists have considered the possibility of transmitting long-distance messages via neutrinos, which pass through a solid such as Earth at nearly the speed of light.
Researchers stay away from politics to focus on science, although they are at the mercy of the governments that provide funding.
A US group remains at Juno, supported by the National Science Foundation, which recently renewed its funding for the collaboration for another three years, the group’s lead physicist told Reuters.
In contrast, more than a dozen American institutions participated in Juno’s predecessor, the Daya Bay Experiment, also in Guangdong.
“Regardless of any political differences, I believe that through our collaboration on this scientific endeavor, we are setting a positive example that will contribute, even in a small way, to bringing our countries closer together.” Can give,” J. said Pedro Ochoa-Ricoux. University of California, Irvine.
data integrity
The neutrino’s passage from the two power stations will be logged by Juno’s 600-metric-ton spherical detector, which will instantly transmit the data electronically to Beijing. The data will be relayed simultaneously to Russia, France and Italy, where it can be accessed by all partner institutions, said Cao Jun, Juno’s deputy manager.
Data integrity has been a concern among foreign companies in China since the implementation of a law in 2021 on the use, storage and transfer of data in the name of protecting national security.
“We have a protocol in place to ensure that no data is missing,” Cao said.
For data on more important aspects of the experiment, at least two independent teams will conduct the analysis, whose results will be double-checked.
“When these two groups get a consistent result, we can publish it,” Cao said.
US-based Ochoa-Ricoux, who previously collaborated on China’s Daya Bay experiment, will lead data analysis for Juno. He will also be involved in DUNE data analysis.
“We welcome the Americans,” said Wang, director of Fermilab’s Chinese counterpart, the Institute of High Energy Physics.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)