I think only the shells of the superconducting coils are cooled to those temperatures. The rest of the system, including the containment walls, are water-cooled.
In a real system you would also have neutron radiation carrying away energy that could be captured with additional layers of water.
I think only the shells of the superconducting coils are cooled to those temperatures. The rest of the system, including the containment walls, are water-cooled.
In a real system you would also have neutron radiation carrying away energy that could be captured with additional layers of water.