J. Feuvrier

TL;DR: In this article, the performance of the Nb3Sn conductor was evaluated in the TQS03 series using a shell structure assembled with keys and bladders, and the authors reported on the strain gauge measurements performed during assembly, cooldown, excitation and quench behaviour of the two magnets.

Abstract: The high gradient quadrupole magnet is a 120-mm-aperture, 1-m-long Nb3Sn quadrupole developed by the LHC Accelerator Research Program collaboration in support of the High-Luminosity LHC project. Several tests were performed at Lawrence Berkeley National Laboratory in 2010-2011 achieving a maximum gradient of 170 T/m at 4.4 K. As a next step in the program, the latest model (HQ01e) was sent to CERN for testing at 1.9 K. As part of this test campaign, the magnet training has been done up to a maximum current of 16.2 kA corresponding to 85% of the short sample limit. The ramp rate dependence of the quench current is also identified. The efficiency of the quench heaters is then studied at 4.2 K and at 1.9 K. The analyses of the magnet resistance evolution during fast current discharge showed evidence of quench whereas high energy quenches have been successfully achieved and sustained with no dump resistor.

TL;DR: Ravaioli et al. as mentioned in this paper proposed coupling-loss induced quench system (CLIQ) for the protection of high-field superconducting magnets, which targets a fast and homogeneous transition to the normal state of the winding pack, hence assuring a quick magnet discharge and avoiding overheating of the coil's hot spot.

TL;DR: In this paper, the coupling-loss induced quench system (CLIQ) was tested for the first time on a Nb3Sn magnet in the CERN magnet test facility in order to investigate its performance in practice.

TL;DR: The Nb$_3$Sn block coil dipole magnet FRESCA2 was developed within the framework of a collaboration between CEA Saclay and CERN as discussed by the authors.