Scientists and engineers at the European Organization for Nuclear Research, CERN, running the Large Hadron Collider (LHC), the world’s largest particle accelerator, restarted it on Sunday after a two-year shutdown for major upgrade.
The upgrade was implemented to allow physicists to extend their ability to probe deeper to unravel the fundamental forces underlying the structure of our physical universe.
According to a statement announcing the restart of the particle accelerator released by the Geneva-based CERN, “After two years of intense maintenance and several months of preparation for restart, the Large Hadron Collider, the most powerful particle accelerator in the world, is back in operation.”
The LHC, consisting of a ring-shaped underground tunnel about 17 miles long (27 kilometers) straddling the Franco-Swiss border, is currently the principal equipment available to scientists worldwide in efforts to unravel the structure of the universe at the small scale.
CERN scientists announced discovery of the Higgs boson particle in 2013 after a series of experiments using the LHC. Existence of the Higgs boson, popularly called the “God Particle,” was first proposed by the British physicist Peter Higgs in the 1964. The Higgs boson is believed to be the particle which confers mass on matter.
Following discovery of the Higgs boson, scientists decided to upgrade the LHC by nearly doubling its energy level. Doubling the energy level of the particle accelerator allows scientists to explore the physics of the universe closer to the moment of its big bang “creation.”
CERN shut down the LHC in February of 2013 to implement a two-year, $150 million overhaul that increased the LHC’s highest attainable energy level from eight tetraelectronvolts (TeV) to 13 tetraelectronvolts.
Scientists and engineers said that the newly-upgraded machine has the potential capacity to reach 14 tetraelectronvolts if required.
CERN scientists restarted the LHC on Sunday by shooting two protons beams through the tunnels at near the speed of light. The initial run will be used to conduct a series of systems tests and checks before technicians begin to increase the energy of the beams.
“Today (Sunday) at 10:42 a.m. (0842 GMT) a proton beam was back in the 27-kilometer (17-mile) ring, followed at 12:27 p.m. by a second beam rotating in the opposite direction.”
After restarting the LHC, Frédérick Bordry, CERN director for accelerators and technology, said the LHC was “in great shape” and that they plan to increase the energy of particle collisions to 13 TeV by June.
Scientists shoot proton beams traveling at close to the speed of light through the tunnels and allow them to collide. The high-energy collisions generate novel, but transient particles which can be detected using special sensors.
The type of particles detected give scientists vital clues about otherwise hidden aspects of the physics of the universe, especially at the early stages of its evolution. The insight obtained helps to elucidate the fundamental forces that shape the evolving physical universe.
Scientists plan to use the next series of experiments to generate higher energy level particle collisions than previously attained when the Higgs boson was first detected. They hope that at the new and higher energy levels they will be able to detect dark matter, antimatter and parallel universes predicted by scientific theories.
No one has ever detected or observed dark matter but scientists have inferred its existence form calculations and observations of its gravitational force effects in the galaxies.
Dark matter is believed to comprise up to 80 percent of mass in the universe.
According to CERN spokesman Arnaud Marsollier, the ability to detect darker matter will lead to a deepening of scientific understanding of the physics of our universe.
“The LHC will be running day and night. When we will get results we don’t know. What is important is that we will have collisions at energies we’ve never had before. If something interesting appears in this new window we will see it. It might be two months from now or two years, we’re not able to say. It took 50 years to find the Higgs boson and 20 years to build this machine, and it will be running at least until 2035, so we can be patient.”
Restarting of the LHC was delayed several days following a short circuit in one of the LHC’s magnetic circuits.
[Images: Wikimedia Commons]