If you know anything about the Large Hadron Collider, you know that it is huge. Massive. 17 miles of tunnels under Switzerland. Traditional accelerators need all that space to get particles to smash into each other at close to the speed of light. But scientists at Stanford have come one step closer to a new type of particle accelerator that could do the same at just a fraction of the size.
The key idea is plasma wakefield acceleration, and as the name implies, it's a bit like riding the wake behind a boat. Symmetry Magazine explains in detail:
Researchers sent pairs of electron bunches containing 5 billion to 6 billion electrons each into a laser-generated column of plasma inside an oven of hot lithium gas. The first bunch in each pair blasted all the free electrons away from the lithium atoms, leaving the positively charged lithium nuclei behind—a configuration known as the "blowout regime." The blasted electrons then fell back in behind the second bunch of electrons, forming a "plasma wake" that propelled the trailing bunch to higher energy.
The idea of particle wakefield acceleration has been bandied around for decades, but it's the first time scientists have achieved that "blowout regime" and boosted particles to such high energies. To put some numbers on it, this gives particles 400 to 500 times as much energy as a traditional accelerator would over the same distance.
The LHC is our most advanced particle accelerator yet, but eventually, we'll want more powerful accelerators to study particles bigger than the Higgs that could be the source of dark matter. The size and cost of these accelerators, however, would be formidable. And CERN, which runs the LHC, has already uses enough electricity to power 300,000 homes. The likely solution would be to think small, think plasma wakefields. [Symmetry, LiveScience, Nature]
Top image via SLAC