The Large Hadron Collider, the particle accelerator that enabled the discovery of the Higgs boson, is back in action after over three years in hiatus. CERN shut the accelerator down for maintenance and upgrade work that was extended due to delays caused by the COVID-19 pandemic. Now, it's ready to smash particles for various research projects throughout its third run that's scheduled to last until 2026. In fact, two beams of protons had already circulated in opposite directions around the 27-kilometer collider as of April 22nd at 12:16 CEST (6:16AM Eastern Time).
It's just a start, however: The beams contained a relatively small number of protons and circulated at 450 billion electronvolts. The LHC team will ramp up the energy and intensity of the beams until the accelerator can perform collisions at a record energy of 13.6 trillion electronvolts.
Mike Lamont, CERN's Director for Accelerators and Technology, said:
"The machines and facilities underwent major upgrades during the second long shutdown of CERN's accelerator complex. The LHC itself has undergone an extensive consolidation programme and will now operate at an even higher energy and, thanks to major improvements in the injector complex, it will deliver significantly more data to the upgraded LHC experiments."
Research teams using the accelerator for their studies are expecting to be able to perform a lot more collisions — one, in particular, is expecting a 50 times increase — thanks to the upgrade. The more powerful LHC will allow scientists to study the Higgs boson more closely and to resume their hunt for a particle that proves the existence of dark matter with a more capable tool at hand.
At the moment, dark matter is but a hypothetical form of matter that's believed to be five times more prevalent than its ordinary counterpart. It's invisible, doesn't reflect or emit light, and all attempts at looking for it have so far been unsuccessful. LHC researchers have narrowed down the regions where the particle may be hidden, though, and the upgraded accelerator could bring us closer to its discovery. To note, CERN previously approved plans to build a more powerful $23 billion super-collider that's 100 km in circumference, but its construction isn't expected to begin until 2038.