Update on the LHC

The Large Hadron Collider (LHC) is offline for now. A helium leak was discovered and perhaps some electrical problem with the magnets.

The magnets that keep the beam going in the ring are superconducting, and thus must be cooled to liquid helium temperatures to work. In order to fix them, they need to be warmed back up to room temperature. The reason for warming them up is similar to the reason for shutting off the circuit breaker in your house before working on the wiring, except here the risk is not of electrocution, but of being instantly frozen to death.

So the whole thing has to be warmed up to room temperature, and it must be done gradually to avoid cracking materials or creating more leaks. The magnets must be warmed up slowly for the same reason that you don't take a regular glass pan from the freezer and stick it in the oven - crack!

Once everything is warmed up, problems will be fixed, then everything gradually cooled back down to liquid helium temperatures. I told a could people that I thought that this would only take a month or two.

But... there was already a planned shutdown for the winter, so the LHC won't be back online until spring. We'll just keep waiting for those insanely high-energy collisions to see if they shed new light on physics.