Cold test results of the FAIR super-FRS first-of-series multiplets and dipole
Résumé
Within the collaboration between GSI and CERN, a dedicated cryogenic test facility has been built at CERN (Geneva, Switzerland) in order to perform the site acceptance tests of the 56 Superconducting FRagment Separator cryomodules before their installation at the the Facility for Antiproton and Ion Research (Darmstadt, Germany). Two of the three benches of the CERN test facility were successfully commissioned with the powering tests of the first-of-series multiplets and dipole. The long multiplet, with a warm bore radius of 192 mm, is composed of nine magnets of different type (quadrupole, sextupole, steering dipole and octupole) assembled with Nb-Ti racetrack and cosine-theta coils, mounted in a cold iron yoke and in a common cryostat. This work presents the first results of the cold powering tests at 4.5 K during which dedicated measurements have been implemented for the magnetic characterization of the single magnets up to nominal current (300 A for a long quadrupole) and the study of their crosstalk effects. The results of the acceptance tests will be presented together with the challenges and lessons learnt during the facility commissioning.