Magnetic refrigeration down to 1.6 K for the future circular collider $e^+e^-$

Jakub Tkaczuk (1) , François Millet (1) , Jean-Marc Duval (2) , Bernard Rousset (2)

1 LCF - Laboratoire de Cryogénie pour la Fusion
2 SBT - Service des Basses Températures

High-field superconducting rf cavities of the future circular collider e+e- may require a kW-range superfluid helium refrigeration down to 1.6 K. Magnetic refrigeration operating below 4.2 K can be an alternative to the compression/expansion helium refrigeration. A significant difference between this application and previous magnetic refrigerator studies is its large cooling power, up to 103 times larger than the other designs. Principles of magnetic refrigeration are described and various technical solutions are compared. A numerical model for the static magnetic refrigerator is presented, validated, and adapted to the needs of the positron-electron version of the future circular collider. A preliminary design of magnetic refrigerator suitable for low temperature, kW-range cooling is studied.

Mots clés: experimental equipment; cryogenics; helium: superfluid; temperature: low; cavity: superconductivity; magnetic; FCC; electron positron; numerical calculations

Domaines: Physique des accélérateurs [physics.acc-ph]

Jakub Tkaczuk, François Millet, Jean-Marc Duval, Bernard Rousset. Magnetic refrigeration down to 1.6 K for the future circular collider $e^+e^-$. Phys.Rev.Accel.Beams, 2017, 20 (4), pp.041001. ⟨10.1103/PhysRevAccelBeams.20.041001⟩. ⟨hal-01555148⟩