FSU Jena, Jena, Germany
GSI, Darmstadt, Germany
IPHT, Jena, Germany
HIJ, Jena, Germany
IOQ, Jena, Germany
Supracon AG, Jena, Germany
New versions of Cryogenic Current Comparator (CCC) sensors with eXtended Dimensions (CCC-XD) for beam line diameters up to 150 mm (necessary for the planned new Facility for Antiproton and Ion Research (FAIR) at GSI (Gesellschaft für Schwerionenforschung) have been realized. These non-destructive charged particle beam monitoring systems are able to measure intensities in the nA-range with a white noise level below 5 pA/sqrt(Hz). The systems are sensitive from DC to several hundred kHz and can be linked-up in a traceable way with national and international ampere-standards. In its present design, the base body consists of a highly-permeable, nano-crystalline core optimized for low-temperatures (ready for superfluid He-II applications) and a niobium shielding/pickup-coil unit. The flexible SQUID (Superconducting Quantum Interference Device) - cartridge allows for application tuning. Three cartridge versions (direct, balanced and enhanced) will be presented, discussed and results of electrical laboratory measurements of the noise behaviour and the frequency response will be given.
GSI, Darmstadt, Germany
TEMF, TU Darmstadt, Darmstadt, Germany
CERN, Geneva, Switzerland
FSU Jena, Jena, Germany
IPHT, Jena, Germany
HIJ, Jena, Germany
IOQ, Jena, Germany
The University of Liverpool, Liverpool, United Kingdom
Supracon AG, Jena, Germany
Triggered by the need for current measurement in the nA range for slow extracted beams and for the beams in the storage rings at FAIR and CERN, the idea of the CCC as a current transformer has been revitalized during the last ten years. Compared to the first prototype, developed at GSI in the 90s, the second generation of CCCs is based on the possibility of detailed simulation of superconducting magnetic shielding properties, new nano-crystalline materials for the magnetic ring-cores, and on superior commercially available SQUID systems. In 2014, nA resolution measurements at 2 kHz bandwidth demonstrated the possibility of spill analysis at slow extracted beams from GSI SIS18. In the following year, the first stand-alone CCC system, including a cryostat with separate He liquefier, started operation in the CERN AD. Although the existing systems show an outstanding current resolution, their cost efficiency and robustness, as well as noise and vibration sensitivity can still be improved, which is subject of ongoing research. In this contribution recent results of our CCC tests are shown and future developments are discussed.
