A cryomodule is a section of a modern particle accelerator composed of superconducting RF (SRF) acceleration cavities, which need very low operating temperatures (often around 2 Kelvin).
The cryomodule is a complex, state-of-the-art supercooled component in which particle beams are accelerated for scientific research.
The superconducting cavities are cooled with liquid helium.
A cryomodule section of an accelerator is composed of superconducting cavities that accelerate the beam, also including a magnetic lattice that provides focusing and steering.
SRF cavities tend to be thin-walled structures immersed in a bath of liquid helium having temperatures of 1.6 K to 4.5 K. Careful engineering is required to insulate the helium bath from the room-temperature external environment.