What Are the Uses of Cryogenics in Large Particle Accelerators?

[Mitchell316]

I do know that for large particle accelerators ( LHC, Fermilab) that the use of cryogenics is used, which is anything below -150C. LHC for example uses liquid helium to create a temperature of about 4K. For smaller particle accelerators though, let's say around 3m in diameter, is the use of cryogenics needed and if so would it need to be cooled to such an extreme temperature?

 

[Vanadium 50]

It's not the size, it's the design. There are (or were) Fermilab accelerators that were large and did not require cryogenics.

 

[Mitchell316]

That being said, what are the cryogenics used for on the LHC and others? Possibly to help with create the near perfect vacuum or to cool down the equipment needed to power the electromagnets?

 

[Vanadium 50]

The LHC magnets are superconducting, so they need to be kept cold. This helps with vacuum, to be sure, but that's not why they do it.

 

[mfb]

Superconducting magnets are important if you want a high energy without building even larger tunnels. The LHC needs them, small particle accelerator usually do not - it is cheaper and easier to make the ring larger.

 

[ChrisVer]

That being said, what are the cryogenics used for on the LHC and others? Possibly to help with create the near perfect vacuum or to cool down the equipment needed to power the electromagnets?

For LHC you can check this one:

http://home.web.cern.ch/about/engineering/cryogenics-low-temperatures-high-performance