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Neutrinos are tiny particles that may hold secrets to some of the universe's greatest mysteries.
The DUNE project hopes to learn more about these 'ghost particles', which are difficult to study.
To do this, the project will emit neutrinos over a distance of 800 miles between Illinois and South Dakota.
Nearly seven years ago, crews began extracting 800,000 tons of rock from a former gold mine near Lead, South Dakota.
The three resulting underground caverns are 150 meters long and almost high enough to house a seven-story building.
The DUNE (Deep Underground Neutrino Experiment) project, which is estimated to cost at least $3 billion, is led by scientists from the US Department of Energy. Fermilab.
Ultimately, each cave will contain 17,500 tons of liquid argon to help Fermilab physicists detect elusive particles known as neutrinos, also known as "ghost particles."
Neutrinos are subatomic particles all around you, passing right through you unnoticed. The sun creates them; they make supernovae; even bananas produce neutrinos.
"If you hold your hand up, 10 billion neutrinos from the sun pass through your hand every second," physicist Mary Bishai and spokesperson for DUNE told Business Insider.
Neutrinos are called ghost particles because they have no electrical charge and therefore rarely interact with anything they come into contact with.
This also makes them extremely difficult to study, yet scientists persist because neutrinos could hold the key to unlocking the secrets of the universe, from what happened just after the Big Bang to observing the birth of a black hole.
A neutrino beam between Illinois and South Dakota
Studying a particle that does not emit radiation and is lighter than an electron is difficult. "Neutrino interactions are almost like needles in a haystack," Bishai said.
And scientists at Fermilab want to use DUNE to study neutrinos in unprecedented detail, like never before.
That is why DUNE will have the largest neutrino detectors of their kind ever built.
The story continues
Once complete, the experiment is intended to begin at a series of particle accelerators at Fermilab outside Chicago, Illinois.
The accelerators will first fire an extremely powerful beam of neutrinos through a detector in Fermilab. The beam then travels 800 miles underground to the detectors at the South Dakota Sanford Underground Research Facility.
Along the way, the neutrinos will do something strange. There are three types of neutrinos, and the particles can switch back and forth between these types, a phenomenon known as oscillation. A Fermilab scientist likened it to a house cat that turns into a jaguar and then a tiger before returning to its original form.
By tracking how the neutrinos change over such long distances between Illinois and South Dakota, scientists can better understand these oscillations, giving them a more complete picture than Fermilab's current 500-mile NOvA experiment between Illinois and Minnesota.
Doing all this a mile underground protects the delicate, oscillating particles from energetic cosmic rays that pass over the Earth's surface every second and could disrupt the data.
Solving the mysteries of the universe
Scientists hope to answer three main questions with DUNE: why the universe is made of matter instead of antimatter, what happens when a star collapses, and do protons decay?
"Right after the Big Bang, almost as much matter as antimatter was created," Bishai said. But as far as scientists can tell, the universe today is made up almost entirely of matter.
"Why did we end up with a matter universe, and not an antimatter universe?" she added.
DUNE's beam is designed to create both neutrinos and antineutrinos - the antimatter version. By looking at the oscillations in each type, scientists can figure out what happened to all the antimatter.
The project is also set up for supernova physics, Bishai said.
In 1987, astronomers witnessed a bright supernova that exploded closer than any seen in about 400 years. With the detectors at the time they could only detect a few dozen neutrinos.
There is a 40% chance that another nearby star will explode in the next decade, Bishai said, and Fermilab hopes at least one of its South Dakota detectors will be operational in time.
Such a large detector could capture thousands of neutrinos and provide insight into how both black holes and neutron stars are formed.
Finally, scientists have not yet seen protons decay, but theory predicts that they would. Protons are small, positively charged particles that are part of the nucleus of an atom.
Observing proton decay would have implications for Albert Einstein's belief that a single theory could unify all the forces in nature.
If protons decayed, it would take roughly 10 billion trillion, trillion years. But neutrino detectors can look for different signatures of proton decay, Bishai said. "We might have a chance to see them, if these grand, unified theories are correct."
An ambitious project
There are currently several neutrino projects around the world, including at the Japan Proton Accelerator Research Complex (J-PARC) and the European Organization for Nuclear Research (CERN).
What makes DUNE unique is the use of argon and the long distance between the near and far detectors.
The project has suffered some budget and timeline setbacks, Scientific American reported in 2022. It is supposed to have four argon detectors, but will start with two.
The first could be operational by the end of 2028, Bishai said, while the second detector would follow next year. These will be there in case a supernova explodes, but the beam part won't be ready until 2031.
That said, Bishai thinks the project has already achieved one of its greatest achievements: a collaboration of about 1,400 people from 36 countries. "It's big science," she said. "It's also great international science."
Read the original article on Business Insider
