Magnetic devices of the Amsterdam pulse stretcher ring AmPS

AmPS is a 900-MeVa electron pulse stretcher and storage ring. The ring contains 170 magnetic elements: dipoles, quadrupoles, sextupoles, steering magnets, and magnetic septa. The magnets were designed with the help of the Poisson code and by using conformal mapping methods. A prototype was made of each type of magnet, mainly to optimize the pole end chamfering. The required low harmonic content could be obtained by simple cuts of the pole ends. The steering magnets combine horizontal and vertical steering and have been designed for a low harmonic content as well. The injection septum with a septum thickness of 3 mm operates at a maximum current of 1075 A. This septum is indirectly cooled. A novel electrical isolation technique is applied which also ensures a good thermal contact between the conductor and the yoke. The extraction septum is directly cooled. A computerized x-y-z field mapping device was developed as well as an inexpensive rotating coil measurement system.<>