By successfully performing a dry run with other subatomic particles, physicists have achieved a significant advancement in the transportation of antimatter.
In addition to being the first time loose particles have been moved in this manner, it opens the door to a means to carry antimatter from CERN to labs that can analyze it more precisely than ever before.
Since antimatter tends to destroy any container it gets into, it doesn’t transport well. However, CERN researchers have created a unique trap they call BASE-STEP that has the ability to contain and move this peculiar material.
In late October, the researchers loaded a cloud of 70 unbonded protons into the trap, loaded it into a truck, and drove it across CERN’s main site to show that BASE-STEP functions as intended. Fortunately, the delicate cargo made it through the brief journey.
“If you can do it with protons, it will also work with antiprotons,” says Christian Smorra, a scientist at CERN and the BASE-STEP principal investigator. “The only difference is that you need a much better vacuum chamber for the antiprotons.”
Since a particle and its antiparticle have opposite charges, antimatter is essentially the “evil twin” of conventional matter. It may seem straightforward, but the consequences are profound. In an energy explosion, antimatter particles annihilate one another when they come into contact with those of conventional matter, including air.
Because of this, antimatter often has a short lifespan, making it difficult to create and even more difficult to research. One of the only facilities on the planet capable of reliably producing antimatter is CERN’s Antiproton Decelerator (AD), which feeds the material into a number of adjacent experiments that investigate it from various angles.
Antimatter must be suspended in an electromagnetic field to prevent it from reaching the sides in order to store the material long enough to be studied. This is exactly what the BASE experiment does, and it has a year-long storage capacity for antimatter particles. However, the number of tests that may be conducted on-site is limited.
According to Stefan Ulmer, a particle scientist at CERN, “the accelerator equipment in the AD hall generates magnetic field fluctuations that limit how far we can push our precision measurements.”
“If we want to get an even deeper understanding of the fundamental properties of antiprotons, we need to move out.”
For this reason, CERN created BASE-STEP, a scaled-down, portable variant that is just one-fifth the size of BASE and measures 1.9 meters (6.2 feet) in length. A lot of equipment is packed into that tiny area in order to protect antiparticles from the shocks and tremors that come with a road trip.
BASE-STEP includes a cryogenic system that cools the superconducting magnet using liquid helium, a vacuum chamber to contain the antiparticles, batteries to power the entire apparatus, and a superconducting magnet to generate the electromagnetic fields required to suspend the particles.
Instead of using antimatter particles for this initial test run, the scientists used 70 loose protons, which are likewise shock-sensitive. These unbonded particles will be drawn back into atomic nuclei if they move around too much because they are simply aching to make new bonds. If they don’t make it, they are much less valuable to lose.
The protons made their way across the complex by truck, and the run was successful. Next year, the team hopes to transfer its first shipment of antimatter after some additional adjustments. In 2025, a different experiment named PUMA also seeks to accomplish the same goal.
“Eventually we want to be able to transport antimatter to our dedicated precision laboratories at the Heinrich Heine University in Düsseldorf, which will allow us to study antimatter with at least 100-fold improved precision,” Smorra explains.
“Our long-term goal is to deliver it to any lab in Europe. This implies that the truck must be equipped with a power generator. We are looking into this possibility right now.