Which forced the accelerator to shut down in 2008

Feb 24, 2010 07:53 GMT  ·  By
The destruction of a section of the LHC could have been prevented, a report shows
   The destruction of a section of the LHC could have been prevented, a report shows

Though the Large Hadron Collider (LHC) is operational at this point, engineers working on the international project are painfully aware that the largest physics experiment in the world is more than a year behind schedule. It is also operating at a fraction of the energy it is capable of, analysts add, and the current program shows that the machine will only be brought to its maximum energy output level in 2013. Now, more than a year after the 2008 crash that hampers operations, engineers say that faulty connections and human errors were largely responsible for the failure, Nature News reports.

“Any technical fault is a human fault,” says bluntly expert Lucio Rossi. He is one of the physicists who oversaw the construction and assembly processes of the large superconducting magnets which fill the LHC's 27-kilometer-long tunnels. On February 22, he published a paper in an Institute of Physics (IOP) journal, showing that poor design and lack of proper diagnostics and quality assurance methods led to the devastation that occurred on September 19, 2008. He concludes that the glitch was not a freak accident, but something that could have been easily prevented, had the necessary measures been taken in due time. He adds that all the new warning systems installed on the accelerator after the glitch should have been there in the first place.

Engineers were, in the last year or so, been able to determine the exact chain of events that led to the destruction of a section of the LHC. They say that the main culprit for the accident was a single connection between two superconducting magnets. The faulty link began warming up at one point, and did so until it lost its ability to carry electrical current. Generally, these connections are cooled by liquid helium, which keeps the components at low enough temperatures for the materials to become superconductors. When the link lost its ability to allow current to pass, thousands of amps of energy simply arced in the machine.

They produced a massive hole in one side of the device, which allowed several tons of the superconducting helium fluid to be drained inside the tunnels. As the helium expanded from its cold temperatures, it produced massive damage, spreading into the ultraclean beamline that was used for proton acceleration, and basically ripping a large number of magnets from the ground. This is one of the main reasons why engineers needed more than a year to repair the damage. They had their work cut out for them. In addition to reverting the system to its initial state, they also installed new security systems, such as sensors capable of detecting the build-up of heat in the connections between superconducting magnets.