New method of field measurements for small-aperture magnets

The possibility of a new method for measuring the magnetic fields of very small-aperture magnets for linear colliders is discussed. The principle of this method is that a single wire with a not negligibly small radius is revolved with a constant frequency in a circle and the frequency spectrum of the induced voltage is analyzed. In actual cases, instead of revolving the wire, the magnet is revolved by a two-dimensional mechanism, which is driven by piezoelectric transducers and undergoes feed-back by a system with laser interferometers. The effect of the sensing-wire shape is also discussed.