The world's most powerful particle accelerator will go live again in June at the earliest, after a shutdown in September.
The European Organization for Nuclear Research (CERN), which runs the Large Hadron Collider, previously suggested that the apparatus would be restarted in April, following maintenance. On Monday, however, it emerged that June would be the earliest possible date for operations to resume fully. It also became apparent that the cost of the repairs alone could be as high as $16 million.
The LHC is housed in a 17-mile-long circular tunnel nestled beneath the Swiss-French border in the Alps. It is designed to shoot streams of particles around the tunnel in opposing directions, smashing them into each other and thereby hopefully discovering more about the origin and nature of matter and the universe.
The particle beams are held on their paths by dipole magnets and focused by quadrupole magnets. These magnets are made of a superconducting material that needs to be cooled by liquid helium to a temperature of 1.9 kelvins (3.4 degrees Fahrenheit), if it is to avoid overheating and exploding.
The LHC was successfully turned on in September, but little more than a week later, an electrical fault caused a helium leak that necessitated the complete shutdown of the machine.
This week, details began to emerge about the cost of the necessary repairs and the likely resumption date for the LHC. Repair time aside, the process will also be slowed down by the fact that the LHC needs to be out of service throughout winter; as it uses a tremendous amount of electricity, CERN cannot risk power issues at a time when citizens' homes need to be heated.
"We already said the bare minimum (repair time) included two months to warm up the sector (from its cryogenic state)," a CERN representative told ZDNet UK on Tuesday. "It became clear that there was no way of doing that before we shut down the accelerator complex for winter, anyway, so that puts the earliest possible date (for the refreezing of the LHC to start) in May. When we start up our accelerator complex, getting it up and running again takes a few weeks, so that takes you into June."
CERN said the glitch and resulting shutdown had been educational, as "markers" had been identified that show when such an incident is likely to occur.
"Those markers would have allowed us to stop (the LHC before the helium leak), had we known where to look," the representative said. "We're building in additional monitoring and protection systems to make sure this kind of incident won't happen again, and this will take time."
CERN's scientists are currently working on a detailed cost analysis and timetable for the necessary repairs and subsequent reinitiation of the LHC, and will present that timetable to the organization's governing body next month.
"We expect that the repairs and the (installation of additional monitoring systems) will cost us between 10 million and 20 million Swiss francs ($8.4 million to $16.8 million)," CERN's spokesperson said. However, because the repairs will eat into CERN's supply of spare parts for the LHC, a second phase of the resumption operation will involve buying more spares, thereby raising the total costs further.
The costs for repairing the LHC and buying new spares would be "accommodated within CERN's annual budget," the spokesperson said, and the organization would not be requesting additional funds from European member states for those purposes.
David Meyer of ZDNet UK reported from London.