Crew members pose for a photo during the construction of DUNE
Crew members on the construction of DUNE

Of all the billion-dollar physics experiments, I’m particularly fond of those that have a “does what it says on the tin” name: the Extremely Large Telescope, the International Space Station . . . and now there’s a new one to add to the list: the Deep Underground Neutrino Experiment. The DUNE project will investigate the neutrino – the tiniest of fundamental particles, meaning “the little neutral one” in Italian. It is being constructed one mile deep below Sanford Lab in South Dakota.

Neutrinos are so tiny that they barely interact with anything and simply glide straight through you, through the Earth and out the other side. But these particles have a mighty role to play in helping us understand some of the most fundamental questions in physics: What is the origin of matter and why is there an imbalance of matter and anti-matter? Is there a grand unifying theory that connects all forces? How do black holes form?

More than 1,000 scientists and engineers, from 200 labs and universities across 30 countries, are collaborating to build DUNE in the hope it will reveal key information about this mysterious particle. The DUNE experiment starts with an underground particle accelerator, where particles will smash into a target to generate an intense beam of neutrinos that will travel through the ground towards the detectors. That’s the easy part. The real challenge is in the design and construction of huge, highly complex detector systems that are capable of seeing a particle that doesn’t want to be seen.

Each of four detector modules will be a liquid-argon chamber filled with 17,000 tons of argon. Neutrinos colliding with argon atoms will produce charged particles that in turn knock out electrons that will be detected by 150 2.3m x 6m units of tightly-wound copper beryllium wires, thus providing a signal that can be recorded as neutrino data. And now the DUNE collaboration has announced the exciting news that mass production for this first, colossal detector module has started, after a series of successful prototype tests at CERN.

This piece is from the New Humanist summer 2023 edition. Subscribe here.