After all the excitement and anticipation surrounding the Large Hadron Collider's launch last September, its first few months have been an anticlimactic cascade of disappointments. When a fault shut down the subatomic particle collider just nine days after the first beam of protons whizzed around its 17-mile track, officials at first said it would take several weeks to repair. Then they revised that estimate, saying it wouldn't be fixed until spring of 2009--and then that changed to summer of 2009. Now, officials say that repairs won't be finished before September, at the earliest.
To appease impatient high-energy physicists, the laboratory will probably run the machine (albeit at reduced powers) for a ten-month stretch from November until the autumn of 2010 [Nature News].
Officials at CERN, the European agency that runs the collider, hadn't planned to run it through the winters when electricity costs are higher; they estimate that this appeasement will cost them an extra $10.5 million for electricity. The repair timeline has stretched out as researchers realized the extent of the damage, and found further flaws in the ring of superconducting magnets, which guide the beams of particles.
In the accident in September, a weld between two sections of the superconducting wire failed. In the minutes after the accident, several tonnes of liquid helium used to cool the magnets vaporized, creating a pressure build-up that wrenched magnets from their concrete stands. In total 53 superconducting magnets must be removed so they can be cleaned, repaired or replaced. Further diagnostic work has since found two more bad welds in magnets in other sectors [Nature News].
To fix the welds, sectors of the LHC need to be warmed up from their freezing cold operating temperature of -456 degrees Fahrenheit, and the liquid helium in those sectors will have to be stored or shunted to another part of the track. The repaired LHC will have a few new safety precautions built in.
CERN is now installing an early-warning system to detect nano-ohm rises in resistance in the superconducting wires that power the LHC's bending magnets. It is also fitting all magnets with additional pressure relief valves to reduce collateral damage in case of a similar incident. Half of the valves will be in place this year [New Scientist].
Despite its slow start, physicists are definitely staying tuned for the LHC to turn back on in September, and for the first particle collisions to occur four to five weeks later. Physicists hope those collisions will reveal the elusive Higgs boson particle, which is believed to endow other particles with mass, and say it could also uncover hitherto unknown particles--or even evidence of other dimensions. The exciting and anticipation is already building. Related Content: 80beats: LHC’s Repairs Will Cost More and Take Even Longer Than Hoped 80beats: LHC Won’t Be Back Online Until Spring of 2009 80beats: Large Hadron Collider Mishap Could Delay Particle Smashing for Weeks 80beats: First Protons Whiz Around the Large Hadron Collider’s Track DISCOVER: The Extremely Long Odds Against the Destruction of the EarthImage: CERN
