Following a two-year overhaul, CERN’s Large Hadron Collider is to begin exploring unknown dimensions of the physical universe
CERN, the European physics research centre located near Geneva, restarted the Large Hadron Collider (LHC) on Sunday, more than two years after it was closed for upgrade work.
Following weeks of cooling procedures, a first beam of protons made its way around the £3.74bn collider at 10:41 a.m. local time on Sunday, followed by a second by 12:27 p.m., scientists said.
“It’s fantastic to see it going so well after such a major overhaul,” CERN director General Rolf Heuer reportedly told scientists and engineers.
The LHC, a 17-mile circular tunnel that is the most powerful particle accelerator and the world’s largest single machine, was built from 1998 to 2008 and initially went live in September 2008, but was shut down after only nine days of operation when a faulty electrical connection caused the rupture of a liquid helium enclosure.
A year later the facility resumed operations and then ran between 2010 and 2013, in 2012 producing evidence that confirmed the previously theorised Higgs boson, part of the “Standard Model” of physics.
During the 2010-2013 run, scientists had taken the precaution of operating the accelerator at half of its design energy, in order to prevent the possibility of another accident such as that which had occurred in 2008. The overhaul carried out since 2013 has been aimed at allowing the machine to produce particle collisions at 13TeV (teraelectron volts), nearly double the energy of the previous experiments.
The upgrade involved reinforcing more than 10,000 connections between components and building in new safety devices. Scientists have also upgraded the back-end computing and storage systems needed to cope with the tens of petabytes of data produced by the experiments.
Beams will initially be run at low power, with plans to increase to the maximum energy over the next two months. The LHC is due to run over the next 20 years.
Until now the machine’s operations have provided some evidence giving credence to the Standard Model, a theory of particle physics dating from the mid-1970s. However, that model is considered as leaving most of the workings of the physical universe unexplained – observable phenomena, such as the movements of celestial bodies, can only be made intelligible through the influence of unseen elements that aren’t included in this model.
These elements are sometimes referred to as “dark matter”, or described as unknown dimensions or as a “supersymmetry” between known and unknown elements; these are some of the theories for which the LHC’s further experiments are intended to search for evidence.
“We could… find something very, very unexpected,” CERN scientist Oliver Buchmueller told Reuters. “This is what makes life on the energy frontier so exciting.”
Are you clued up about Amazon’s cloud computing platform? Try our quiz!