The Large Hadron Collider in Switzerland can often be found colliding particles together at nearly the speed of light, but recently it has begun colliding a new type of particle for the first time: atoms. In a test run on July 25, scientists at the LHC accelerated lead atoms with a single electron and maintained the beam for multiple hours, creating an opportunity for future experiments with these types of particles.
A typical LHC experiment involves sending small particles—usually protons—around a giant ring at a decent fraction of the speed of light. After building up enough speed, the particles crash into each other, releasing huge amounts of energy and breaking into new, more exotic particles. By studying the results of this collision, scientists can learn a great deal about the building blocks of our universe.
Of course, different starting ingredients produce different final results, so scientists at the LHC are interested in sending as many different particles through their accelerator as they can. In the past, they’ve sent entire atomic nuclei through the machine.
This new experiment is a bit different because it features a single electron per atomic nucleus. That electron makes the experiment more difficult because it changes how the atoms behave around the LHC’s magnets. In particular, there’s the risk that if the atoms lose their electrons somewhere inside the complex’s giant ring, it could send those atoms careening into the tunnel walls.
“It’s really easy to accidentally strip off the electron,” says LHC engineer Michaela Schaumann. “When that happens, the nucleus crashes into the wall of the beam pipe because its charge is no longer synchronised with the LHC’s magnetic field.”
However, thanks to delicate engineering, the LHC scientists successfully ran two experiments with these atoms. In the first, they maintained a low-energy beam of atoms for around an hour, before increasing the energy to the LHC’s maximum. They held the atom beam stable at that energy for around two minutes before automatic safeguards shut it down. In a second attempt, the beam was stable at maximum energy for two hours.
The primary benefit for accelerating atoms with electrons attached is that the electrons can generate high-energy gamma rays, which are the most powerful light waves possible. With a reliable source of gamma rays, scientists could perform all kinds of experiments, including trying to produce some of the more exotic types of matter in the universe. They may even be able to generate dark matter.
It will likely be at least another year before the LHC starts running real experiments using this technique, so we’ll have to wait a bit longer to see what new discoveries these scientists can make.
Originally posted on Popular Mechanics USA