TTC/ARIES topical workshop on flux trapping and magnetic shielding

Session

Magnetic shielding

8 Nov 2018, 09:00

31/3-004 - IT Amphitheatre (CERN)

Conveners

Magnetic shielding: Part 1

• Mika Masuzawa (KEK)
• Saravan Chandrasekaran (FNAL)

Magnetic shielding: Part 2

• Saravan Chandrasekaran (FNAL)
• Mika Masuzawa (KEK)

8. Measurement of magnetic shielding performance and permeability of soft magnetic alloys for SRF

Mr Sakakibara (Othama CO)

08/11/2018, 09:00

Magnetic shield products are manufactured through specialized processes, including heat treatment and performance testing of DC magnetic shielding. By May 2018, all of the magnetic shields for the SRF of the FRIB were completed and passed performance tests at room temperature in our factory. Those products are made of mu-metal, a nickel-iron alloy, instead of from an alloy for cryogenic...

9. Small magnetic field measurements and control at CERN

Marco Buzio (CERN)

08/11/2018, 09:25

At CERN, magnetic measurement activities typically concern fields up to about 10 T, with uncertainties in the 10-100 ppm range. In some cases, however, measurement and control of very low fields, in the range of nano to microcrotesla, is needed. In this talk, we shall first review briefly such cases, which are mostly motivated by the mitigation of beam perturbations at very low energy or over...

10. Magnetic field management in cryomodules and vertical cryostats at CEA-Saclay

Juliette Plouin (CEA)

08/11/2018, 09:50

Limitation of the flux trapping in superconducting cavities requires magnetic field management around cavities. At CEA, this activity is carried out both for cryomodules (IFMIF, ESS, SARAF) and test facilities. Appropriate magnetic shielding must be provided, and magnetic field sources must be avoided close to the cavities. This latter point requires the selection of non magnetic material for...

11. Magnetic field management for SRF

Saravan Chandrasekaran (FNAL)

08/11/2018, 10:30

Magnetic field management for SRF cavities has grown in importance with recent projects desiring greater Q, implying smaller magnetic fields at the cavities. This requires cryomodules and facilities to be designed with additional measures, such as global and/or local passive magnetic shielding as well as active methods to reduce fields. I will provide a summary of these techniques as applied...

12. Characterisation of the magnetic shield efficiency for the ESS double spoke cavities

Vateanui Sansine (Institut de Physique nucléaire d'orsay)

08/11/2018, 11:05

Measurements of the efficiency of the magnetic shield have been carried out for the ESS Spoke cavities. The magnetic shield is made of Cryophy, a Nickel-Iron alloy, and is mounted around the Double-Spoke cavity. It is composed of two 1mm-thick layers, actively cooled by cryogenic circuit (LHe @ 4K). The installation of a mock-up cavity in the prototype cryomodule (made of stainless steel) gave...

13. Q&A on Magnetic shielding

08/11/2018, 11:20