Innovative calibration method for rotating-coil magnetometers

Rotating-coil magnetometers, which rely on induction-coil arrays, are commonly used for magnetic measurements of particle accelerator magnets. In order to characterize magnetic fields with high accuracy using the induced voltages, it is essential to calibrate the geometry of the coils. In this thesis we present an innovative method of calibration of the coil radius of rotation which is necessary for determination of the field gradient. The method, called rotating calibration method, is based on two well-known measurement techniques: single-stretched wire and rotating induction-coils. The flux measured with a rotating induction-coil over the entire length of a reference quadrupole magnet is cross-calibrated with a single-stretched wire measurement. In the experimental validation of the method, the radius of rotation of several coils has been calibrated with an accuracy of 10 µm on a radius of 30 mm. The advantage of this method is that the calibration is performed under the same conditions in which the rotating-coil magnetometers are used for measuring accelerator magnets. In the thesis also a proposal for calibration of other geometric factors of a coil by using higher order multipoles is presented.