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

Daniel Barna, Martin Novák, Kristof Brunner, Carlo Petrone, Miroslav Georgiev Atanasov, Jerome Feuvrier, Max Andre Pascal

Research output: Contribution to journalArticle

Abstract

A passive superconducting shield was proposed earlier to realize a high-field (3-4 T) septum magnet for the Future Circular Collider. This paper presents the experimental results of a potential shield material, an NbTi/Nb/Cu multilayer sheet. A cylindrical shield was constructed from two halves, each consisting of four layers with a total thickness of 3.2 mm, and inserted into the bore of a spare dipole corrector magnet of the Large Hadron Collider. At 4.2 K, up to about 3.1 T at the shield's surface, only a leakage field of 12.5 mT was measured inside the shield. This can be attributed to the misalignment of the two half cylinders, as confirmed by finite element simulations. With a better configuration, we estimate the shield's attenuation to be better than 4× 10-5, which is acceptable for the intended application. Above 3.1 T, the field penetrated smoothly. Below that limit, no flux jumps were observed even at the highest achievable ramp rate of more than 50 mT/s at the shield's surface. A 'degaussing' cycle was used to eliminate the effects of the field trapped in the thick wall of the shield, which could otherwise distort the homogeneous field pattern at the extracted beam's position. At 1.9 K, the shield's performance was superior to that at 4.2 K, but it suffered from flux jumps.

LanguageEnglish
Article number4900108
JournalIEEE Transactions on Applied Superconductivity
Volume29
Issue number1
DOIs
Publication statusPublished - Jan 1 2019

Fingerprint

septum
Magnetic sensors
particle accelerators
High energy physics
Superconducting magnets
Colliding beam accelerators
Magnetism
superconducting magnets
Particle accelerators
Magnets
Degaussing
Multilayers
accelerators
magnets
thick walls
Fluxes
ramps
misalignment
leakage
attenuation

Keywords

  • Accelerator
  • Future Circular Collider (FCC)
  • NbTi
  • septum magnet
  • superconducting shield (SuShi)

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Electrical and Electronic Engineering

Cite this

Barna, D., Novák, M., Brunner, K., Petrone, C., Atanasov, M. G., Feuvrier, J., & Pascal, M. A. (2019). NbTi/Nb/Cu Multilayer Shield for the Superconducting Shield (SuShi) Septum. IEEE Transactions on Applied Superconductivity, 29(1), [4900108]. https://doi.org/10.1109/TASC.2018.2872860

NbTi/Nb/Cu Multilayer Shield for the Superconducting Shield (SuShi) Septum. / Barna, Daniel; Novák, Martin; Brunner, Kristof; Petrone, Carlo; Atanasov, Miroslav Georgiev; Feuvrier, Jerome; Pascal, Max Andre.

In: IEEE Transactions on Applied Superconductivity, Vol. 29, No. 1, 4900108, 01.01.2019.

Research output: Contribution to journalArticle

Barna, Daniel ; Novák, Martin ; Brunner, Kristof ; Petrone, Carlo ; Atanasov, Miroslav Georgiev ; Feuvrier, Jerome ; Pascal, Max Andre. / NbTi/Nb/Cu Multilayer Shield for the Superconducting Shield (SuShi) Septum. In: IEEE Transactions on Applied Superconductivity. 2019 ; Vol. 29, No. 1.
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