ByJAMEY KEATEN Associated Press
March 23, 2026, 10:48 PM

GENEVA -- Scientists in Geneva took some antiprotons out for a spin — a very delicate one — in a truck, in a never-tried-before test drive that has been deemed a success.

If this so-called antimatter came into contact with actual matter, even for a fraction of an instant, it would have been annihilated in a quick flash of energy. So experts at the European Organization for Nuclear Research, known as CERN, over the course of four hours Tuesday, brought about 100 antiprotons on the road.

The antiprotons were suspended in a vacuum inside a specially designed box and held in place by supercooled magnets.

After easing them from the lab and onto the truck, the scientists transported the antimatter on a half-hour drive to test how — if at all — the infinitesimal particles could be transported by road without seeping out. The antiprotons were then taken back to the lab in Tuesday's final stage that concluded with applause and a bottle of Champagne.

CERN spokeswoman Sophie Tesauri called the experiment successful. It was not immediately clear how many antiprotons had survived the entire journey, but roughly 91 of 100 were still there after the truck's trip.

The hard part: Manipulating antimatter, like antiprotons, can be tricky business. As scientists understand the universe today, for every type particle that exists, there is a corresponding antiparticle, exactly matching the particle but with an opposite charge.

If those opposites come into contact, they “annihilate” each other, setting off lots of energy, depending on the masses involved. Any bumps in the road on the test journey that aren't compensated for by the specially-designed box could spoil the whole exercise.

“The motivation behind these experiments is to compare matter and antimatter with extremely high accuracy and watch for differences which we might have not seen yet,” said Stefan Ulmer, the leader and spokesperson for Tuesday’s experiment.

And Tuesday’s practice was a first step toward making good on hopes, one day, to deliver CERN antiprotons to researchers at Heinrich Heine University in Düsseldorf, Germany, which is about eight hours away in normal driving conditions.

“We are scientists. We want to understand something about the fundamental symmetries of nature, and we know that if we do these experiments outside of this accelerator facility, we can measure 100 to 1000 times better,” Ulmer said.

The antiprotons were encased in a 1,000-kilogram (2,200 pounds) box called a “transportable antiproton trap.” It was compact enough to fit through ordinary laboratory doors and fit on a truck. It used superconducting magnets cooled to -269 degrees Celsius (-452 Fahrenheit) that allowed the antiprotons to be remain suspended in a vacuum — not touching the inner walls, which are made of ... matter.

The mass in Tuesday's test — slightly less than that of about 100 hydrogen atoms — is so little, experts say, that the worst possible outcome was the loss of the antiprotons. Even if they did touch matter, any release of energy would be unnoticeable, only an oscilloscope, which picks up electrical signals, was be able to detect it.

The trap, says Tesauri, “is supposed to contain these antiprotons no matter what: if the truck stops, if it starts again, if it has to slam on the brakes — all that.” Work remains: The trap can contain the antiprotons on its own for only about four hours, and the drive to Düsseldorf is twice that.

The Geneva-based center is best known for its Large Hadron Collider, a network of magnets that accelerates particles through a 27-kilometer (17-mile) underground tunnel and slams them together at velocities approaching the speed of light. Scientists then study the results of those collisions.

But the sprawling, buzzing complex of scientific experiment is more than just about smashing atoms together: the World Wide Web, for example, was invented here by Britain’s Tim Berners-Lee in 1989.

Heinrich Heine University is seen as a better place to study antiprotons in-depth because CERN, with all its other activities, generates a lot of magnetic interference that can skew the study of antimatter.

But to get them there, those antiprotons will have to avoid touching anything on the way.

The center's Antiproton Decelerator, where a proton beam gets fired into a block of metal, causes collisions that generate secondary particles, including lots of antiprotons. It’s billed as a unique machine that produces low-energy antiprotons for the study of antimatter.

CERN’s “Antimatter Factory,” lab officials say, is the only place in the world where scientists can store and study antiprotons.

The center has been experimenting with antimatter for years, and has made breakthroughs on measurement, storage and interaction of antimatter. Two years ago, the team transported a “cloud” of about 70 protons — not antiprotons — across CERN's campus.

It was a similar drill this time, except that with antiprotons, a much better vacuum chamber is needed, according to Christian Smorra, head of a team behind the apparatus designed to store and transport antimatter.

https://abcnews.com/Technology/wireStory/road-antiprotons-cern-runs-delicate-test-transporting-ultrasensitive-131350304