Division of accelerators, cryogenics and magnetism

Technical means

• H0 magnet composed of 24 NbTi double pancake coils (internal diameter Φ_int = 472 mm and external diameter Φ_ext = 780 mm), cooled by liquid helium bath,
• Electrical circuit which includes the power supply (I < 1800 A), the coil, two current leads (I < 600 A), a magnet protection system based on threshold voltmeters with contactor and discharge resistance,
• Control and acquisition of cryogenic parameters (vacuum, level, temperature, pressure),
• Liquid nitrogen for thermal shielding and pre-cooling; liquid helium supply with Dewar cans.

Achievements, related projects

H0 was originally a prototype of double pancake winding which was built by ALSTOM and tested in the framework of the ISEULT project.

H0 allows to perform R&D studies on high critical temperature conductors and superconducting windings, via a cryogenerator (the station is currently used for characterizing MgB₂ conductors).

The station could also be used for instrumentation tests under magnetic field (temperature and pressure sensor, electronic card...).

It is also planned to use the platform to test prototypes of junctions of superconductors under a field up to 3 T.

Technical steps, expertise

• Possible mechanical adjustments in order to install the component to be tested in the field area.
• Conditioning of the station and its instrumentation,
• Check of the vacuum level,
• Startup of the cryogenic filling (pre-cooling by LN2 exchanger, initial filling for cooling the magnet and then resupplying at regular intervals),
• Securing of the area under magnetic field,
• Magnetic field rise (field measurement, check of the field map when there is a sample which might affect the field generated by the coil),
• Tests on the sample at room temperature, or on the sample cooled with a cryogenerator (variable temperature 4.2 K ≤ T ≤ 300 K) with 600 A current leads.

Contact: