A method for measuring the magnetic fields of undulators based on a wire with a pulsed current is considered. This method is promising for creating a fine-tuning system for undulators, which can work in on-line mode because a single measurement takes only a few seconds. The pulsed wire field measurements were carried out with the superconductive 128-pole undulator with the magnetic field amplitude of 1.15 T and magnetic period of 15.6 mm.
Kazantsev et al. (Wed,) studied this question.