Yesterday just before 11:25 p.m. Central European Time, the first protons of 2010 were injected in the Large Hadron Collider. By 2:45 a.m. CET a proton beam had made hundreds of turns around the 27-kilometer ring in one direction, and the same feat was completed in the other direction by 4:10 a.m. The beams had an energy of 450 billion electron volts (GeV), which is the energy at which they are injected into the LHC.
The circulating beams marked the end of a ten week particle-free hiatus for the world's largest particle accelerator, during which LHC scientists and engineers have prepared the machine for it's biggest challenge yet, particle collisions at an energy of seven trillion electron volts (TeV). The beams also mark the beginning of the LHC's first long run, expected to last until at least mid-year 2011.
Over the next few weeks, the energy of the proton beams will be ramped up toward this year's goal: colliding 3.5-TeV beams in the center of the LHC experiments.
by Daisy Yuhas
