The vaunted Large Hadron Collider (LHC) experienced a significant setback this morning, when temperatures in one sector of the particle collider began to rise, and a ton of liquid helium escaped into one area of the collider's 17-mile tunnel. The mishap follows a previous glitch that occurred one day after the LHC's opening and delayed operations for about a week, but this new incident appears to be more serious and could take several weeks to resolve. The LHC smashes subatomic particles together by send protons whizzing through its circular tunnel to collide at certain points; the beams of protons are kept on track by over 1,600 massive magnets that must be kept at temperature near zero on the Kelvin scale.
The incident was what is known as a “quench”, in which the temperature of superconducting magnets that are normally chilled to 1.9C above absolute zero started to rise. It caused the temperature of many of the 200 or so magnets in the affected sector to soar by as much as 100C, which would normally take about two weeks to be cooled again [The Times].
The LHC's operating organization, known as CERN, hasn't yet revealed the cause of the incident. The problem squashes hopes that the first particle collisions could occur next week, as was announced earlier. (So far, the LHC team has sent particles racing around the track in each direction, but they haven't collided anything yet.)
James Gillies, head of communications at Cern, said: "The incident occurred while we were commissioning the final sector, and a lot of helium has leaked into the tunnel. We are investigating now, and we should have a clearer picture over the weekend. How long it takes to resolve depends on what it is. It could be very little time, or it could be many weeks. I don't want to speculate until we have more information. It certainly means we will not have collisions on Monday, or indeed next week" [Telegraph].
The incident follows a glitch that occurred the day after the LHC opened for business, in which a 30-ton transformer that keeps the magnets chilled broke down and had to be replaced. The LHC's cryogenics team had just finished bringing the magnets back down to the appropriate operating temperature when the second problem occurred. CERN officials say that such setbacks are inevitable when starting up a project of this complexity. Image: CERN Related Posts: First Protons Whiz Around the Large Hadron Collider's Track All Systems Go for World's Largest Particle SmasherThe Large Hadron Collider Will Finally Start Smashing in SeptemberPhysics Experiment Won't Destroy Earth