Cable Magnetization Effects in the LHC Main Dipole Magnets
Several short (1 m) and long (10 m) dipole models have been tested within the scope of the on-going R&D programme for LHC at CERN. We report here the results of measurements of field quality, focussing on the contribution of persistent current magnetization. We show that measurements of the dependence of allowed harmonics on magnetic field at 1.8 K can be computed with reasonable accuracy. The calculation is based on a model of the filament magnetization adjusted to fit available strand data. Low field measurements of the first allowed harmonics, sextupole and decapole, correlate satisfactorily with the filament diameter and the scaling obtained from the simulation program.
KeywordsLarge Hadron Collider1 Minimum Current Filament Diameter Penetration Phase Field Error
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