Abstract
The paper is an account of the design, construction and testing of a pulsed superconducting dipole magnet of novel design known as AC4. It represents a stage in the development of very-high-field magnets for possible use in a super-high-energy proton synchrotron. Though the magnet does not quite attain the necessary field homogeneity, the extensive tests reported here provide confidence and much relevant information for future designs using saturated iron. From electrical measurements of total losses for unidirectional and bidi rectional pulsing, an estimate can be made of the contribution from the iron yoke and shows that the hysteretic losses in the superconductor are about as expected.