Physicists at CERN, the European nuclear research center, say they've shut off the particle beams of the Large Hadron Collider for a two-year repair period.

The collider, famous for identifying a particle believed to be the Higgs boson or "God particle" in late 2012, will undergo repairs and upgrades that will allow it to be run at its full design energy for the first time, they said.

The collider's beams were switched of Thursday morning but it will take until Saturday for the machine's 1,734 magnets to return to room temperature from their super-chilled state, the BBC reported.

The LHC has been operated at particle energies of 8 trillion electron-volts but when the upgrade is completed in late 2014 it should be capable of running at 14 trillion, creating the highest-energy collisions ever attempted by researchers.

Problems with the connections between the giant magnets that steer charged particles around the collider's 16-mile ring have kept it from ever being run at full power, scientists said.

"We have been running successfully, but only at half the maximum energy, because we can only safely run the magnets at half the design current," Tony Weidberg, a University of Oxford physicist who works with the LHC, said.

After testing when the collider is reactivated, experiments are set to resume in February or March 2015, CERN said.