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← Hadron Collider halted for months

Steven Mading's Avatar Jump to comment 8 by Steven Mading

I work in a place with a lot of NMR spectroscopists who also work with low-temperature electromagnets (but not THIS low) and I've heard them use this word "quench" a lot. From what I gather as a total layman it works like this:

The electromagnet needs to be a superconductor in order to maintain such a high strength field. If there is the slightest resistance then it takes too much electrical power to run the magnet. But the superconductors we know how to make require very low temperatures to operate. If some thing fails in such a way that the superconductive material gets even the teeniest bit of resistance, this creates a feedback effect called a "quench". The fact that the material now has resistence means the massive current running through it will now start producing a heat byproduct. As soon as it does that, it makes the material warm up even more, which makes it become even more reistant, which makes it produce even more heat, and so on. The magnet goes from a superconductor carrying massive current to a dead burned out hunk carrying no current, and it does it quickly and can cause a lot of damage to the rest of the apparatus.

Sun, 21 Sep 2008 02:53:00 UTC | #237983