The collider, buried beneath the Swiss-French border, was powered up two weeks ago with great fanfare. Once it's fully functional, the multi-billion-dollar machine will send beams of protons smashing into each other at nearly the speed of light.
Physicists hope the collisions will help prove or disprove some previously un-testable theories about the universe. For example, they may create a never-before-seen particle called a Higgs boson, the so-called "God particle" one theory says gives all other particles mass. Or the collisions may produce evidence of dark matter, the hypothetical matter that some scientists think makes up as much as 80 percent of the universe.
All of that, however, will have to wait until next spring. The collider had a successful first run on Sept. 10, when scientists sent a beam of protons completely around the 17-mile track. But on Sept. 18, an electrical glitch in the cooling system sparked a helium leak in one section of the tunnel.
"This is undoubtedly a psychological blow," European Organization for Nuclear Research (CERN) General Director Robert Aymar said in a news release.
The collider's superconducting magnets, which steer the protons on their course, must be kept at an operating temperature of -271.3 Celsius. So in order to investigate the equipment failure, engineers will have to wait approximately a month for the collider to warm up to room temperature. Once the problem is fixed, it will take another month or so to cool back down. That will take until late November.
Michael Barnett, a physicist at Lawrence Berkeley National Laboratories and the education and outreach coordinator for ATLAS, one of the experiments being run at CERN, says that scientists are waiting along with the public to find out the extent of the damage to the collider, which won't be fully known until it warms up enough to be examined.
"That's the question we're all asking ourselves. How many magnets were damaged? No one really seems to know," he says.
But, he adds, the ATLAS equipment -- the detector that will detect the results of the collisions -- was unharmed.
"We're still doing what we were doing before, which is looking at cosmic rays [...] to sort of tune up," he says.
Because CERN intended to power down the collider in early December anyway for a money-saving winter break (electricity is more expensive in Switzerland in the winter), CERN officials decided this week to wait until spring to power the collider back up.
"The success of the LHC's first operation with beam is testimony to years of painstaking preparation and the skill of the teams involved," Aymar said. "I have no doubt that we will overcome this setback with the same degree of rigor and application."