A flexible printed-circuit coil for scanning transversal magnetic-fields errors in accelerator magnets

The proof of principle of an induction coil sensor for scanning transverse magnetic-field errors is presented. This sensor allows to build a rotating-coil transducer that is not sensitive to the axial magnetic field component in the magnets. The main design objective is to optimize the positions of each coil loop in the sensor’s transverse cross-section, to guarantee the desired sensitivity factors to the specific field-harmonic components. After illustrating the magnetic measurement principle, the design and the manufacturing technology of the flexible circuit board are presented. Then the metrological characterization, the calibration and the functional tests are discussed