The Large Hadron Collider (LHC), the world's largest and most powerful particle accelerator and the machine that found what appears to be the long-sought Higgs boson (a.k.a. "God particle") last summer, is preparing to push the limits of its current configuration in the final weeks before a nearly two-year-long shutdown and upgrade period. The LHC will spend the remainder of the month until mid-February smashing together protons and lead ions, according to an update this week from the European Organization for Nuclear Research (CERN), the organization that oversees the accelerator.
Previously, the LHC was used to smash two like beams of protons together, and only briefly tested the proton/lead-ion collisions for one week in September. As CERN explained the significance of the change in a bulletin:
The LHC was designed to collide two similar beams - either two beams of protons or two beams of lead ions. But if the two beams are of different particles with different mass and charge, they respond differently to the effects of the magnets and travel at different speeds.
The LHC shoots beams around a 17-mile-long underground ring at nearly the speed of light to simulate the conditions of the early universe, shortly after the "Big Bang." But these new collisions will be some of the most trying on the current hardware, prior to the upgrade. As physicist John Jowett was quoted by CERN:
“No-one has ever collided protons and lead ions successfully before, and we have just one month to do it. We have to implement a new set of operational procedures very quickly and then explore how much we can increase the beam intensities,” says Jowett. “It’s going to be a challenging experimental run for the accelerator.”
Image above shows a bottle of Linac 3, the source of lead ions for the experiment.