Just nine days after it was first turned on in September 2008, the Large Hadron Collider at CERN was brought to a standstill when an improperly soldered splice connecting two superconducting cables failed (see PHYSICS TODAY, November 2008, page 24). When it starts back up in November, the plan is to test and debug both the LHC and its experiments for a while at 3.5 TeV per proton beam, then to ramp up to perhaps 5 TeV, hopefully sometime in 2010. Some lingering problems still need to be solved to make it safe to go to the design goal of 7 TeV, or 14-TeV center-of-mass collision energy.
“The first job is to rediscover the standard model,” says LHC project leader Lyn Evans. “Produce the top quark, measure its mass, and use the data to calibrate all the physics we know from the Tevatron,” which produces 2-TeV collisions at...
