Thermohydraulic Quench Back in a Copper CICC Coil Cooled by He II

The MAgnetized Disc and Mirror Axion eXperiment (MADMAX) project aims at detecting axion dark matter in the mass range of 100 μeV. To do so, a dipole detector magnet producing 100 T2m2 is needed. In the framework of an innovation partnership with the Max Planck Institute, CEA Paris-Saclay designed this large-scale magnet producing 9 T in a 1.35-m bore. The magnet is made of a cable in-conduit conductor, operating at 1.8 K. One of the main challenges of this novel design is to guarantee the magnet's safety toward quench management. In order to validate the magnet and conductor designs, a mock-up coil with a quench behavior scalable to MADMAX was designed, manufactured, and cold-tested. This article gives an overview of the main guidelines followed to design the prototype fully representative of the MADMAX quench behavior. The experimental facility, instrumentation, and protocol are presented. The main experimental results are given and extensively analyzed with empirical, analytical, and numerical approaches. This article presents the first experimental observation of the existence of the thermohydraulic quench back phenomenon in stagnant superfluid helium.