Monitoring the magnetic axis misalignment in axially-symmetric magnets

A method for monitoring the misalignment of the magnetic axis in axially-symmetric magnets is proposed. Conversely to the other methods for magnet axis determination, the proposed method is suitable also when the magnet has been deployed and the surrounding equipment has been installed, often making the axis region and almost the whole remaining magnet aperture not accessible. Requiring only a few measurements of the magnetic field at fixed positions inside the magnet aperture, it overcomes the main drawback of the other Hall sensor-based methods which is having to deal with sturdy mechanics of the moving stages. In this paper the analytical description of the method is presented, and the sensitivity concerning the measurement is studied. Then, the validation of the measurement method, based on analytical simulations of the magnetic field inside an ideal solenoid magnetic aperture, is presented.