Magnetic field measurements on small magnets by vibrating wire systems

Abstract

A new method based on vibrating wire to measure field multipole is presented. The magnet multipoles are assessed by positioning the wire in different points on a circle inside the magnet aperture and measuring the amplitude of wire vibrations. An analytical model relates vibration amplitudes to multipoles. Results of simulation tests aimed at analyzing the model performance are reported. Preliminary experimental validation results on small permanent magnets for the new linear accelerator Linac4 at European Organization for Nuclear Research (CERN) are shown.

Multipole correction of stretched-wire measurements of field-gradients in quadrupole accelerator magnets

“…The flow diagram of the correction procedure is shown in figure 2. The position of the quadrupole magnetic axis is determined by means of the vibrating wire method [12]. The wire has the highest response to the transversal magnetic field when excited at its resonance frequency; thus the magnetic axis position is found by minimizing the oscillation amplitude of the wire.…”