“Mirror” magnet experiment for quench studies, quench analysis techniques development and in support of superconducting magnet modeling

Abstract

In order to progress on various research points related to superconducting magnets, we suggest performing series of tests with induced and natural quenches on a mirror magnet, probably using a "11 T" coil. The "mirror" is to have voltage taps instrumented on half the strands, on both coil ends. It is to be instrumented with multiple spot-heaters, of the order of ten, in designated pole-turn areas. Instrumentation is to include quench antenna array facing the inner coil surface, as well as acoustic sensors on the inner layer pole. Further, acoustic sensors at the magnet ends and an acoustic calibration transducer are to be installed. Thus, we are to test sensitivity and precision of acoustic and quench antenna (QA) array sensors, both at close proximity to the coil, and we are to test and commission acoustic onmagnet real-time "calibration". New or extended DAQ will be tested as well. In addition to diagnostic development, the purpose of the magnet experiment is to investigate current redistribution in the coil, both during quenching and in operating conditions; to assess voltage build up across strands and in the coil segments during quenching, to explore voltage signature differentiation between different type of quenches; to improve modeling of processes during quenching and for magnet design purposes. In this experiment, we expect to be able to characterize the processes during a quench in unprecedented details.

Advancing Superconducting Magnet Diagnostics for Future Colliders

“…The intricacies of quench development and current redistribution in Nb 3 Sn magnets are still not mastered [31], creating a need for sub-scale experiments and representative cable tests with well-controlled conductor conditions and a host of versatile instrumentation. Such experiments will improve understanding of natural quenches occurring in state-of-the art accelerator magnets.…”