High field septum magnet using a superconducting shield for the Future Circular Collider

Abstract

A zero-field cooled superconducting shield is proposed to realize a high-field (3-4 T) septum magnet for the Future Circular Collider hadron-hadron (FCC-hh) ring. Three planned prototypes using different materials and technical solutions are presented, which will be used to evaluate the feasibility of this idea as a part of the FCC study. The numerical simulation methods are described to calculate the field patterns around such a shield. A specific excitation current configuration is presented that maintains a fairly homogeneous field outside of a rectangular shield in a wide range of field levels from 0 to 3 Tesla. It is shown that a massless septum configuration (with an opening in the shield) is also possible and gives satisfactory field quality with realistic superconducting material properties.

Effect of Ultra-sonicated Y2BaCuO5 on Top-Seeded Melt Growth YBa2Cu3Oy Bulk Superconductor

“…Bulk REBCO superconductors are mostly used in practical applications such as flywheel energy storage systems, magnetic bearings, trapped field magnets, etc. [3][4][5]. For achieving good superconducting performance, it is necessary to obtain high superconducting critical current density (J c ) and trapped flux density (B T ) at high temperatures and high fields [6].…”

NbTi/Nb/Cu Multilayer Shield for the Superconducting Shield (SuShi) Septum

“…hysteresis simulations. For the nonsymmetrical cases extra parameters (the values of the vectorpotential A z in the interior of the bulk superconductors) were introduced and solved for by requiring that the current density integrated over the cross section of each superconducting piece be zero, as described in [1]. (ii) A time-dependent eddy current simulation using the power-law E-J characteristics…”

“…These requirements are even more important for the high-energy LHC (HE-LHC) option (an alternative to the FCC), which would use FCC technology in the LHC tunnel, where space is very limited. In a recent proposal [1] this field configuration would be realized by the combination of a superconducting magnet and a passive superconducting shield, referred to as a superconducting shield (SuShi) septum in the following. The geometry of the shield and the magnet winding need to be optimized simultaneously to give the required field homogeneity outside the shield.…”

Accelerator Engineering and Technology: Accelerator Technology

“…Although the direct-drive septum could be equipped with a superconducting coil, most superconducting septa are derived from superconducting cosine theta dipoles [205][206][207]. A novel concept under study uses a superconducting tube, used to shield a magnetic field (in principle generated by a superconducting magnet outside the tube), the tube becoming effectively the septum separation between the high field generated by the external magnet and the field-free region inside the tube [208]. This topology is often referred to as the SuShi (superconducting shield) septum.…”