Ramp rate sensitivity in accelerator magnets

Degraded magnet performance, sometimes quite dramatic, was observed in many dipole magnets built for the SSC. A number of magnets which exhibited degraded performance fell into two classes, ingeniously referred to as type open-quotes Aclose quotes and open-quotes Bclose quotes. As a result of a great deal of theoretical and experimental work, considerable progress has been made toward understanding this behavior. This article reviews much of this work, and speculates as to how better magnets might be produced using the results of what has been learned