MURA days

The Midwestern Universities Research Association (MURA),incorporated in the mid nineteen-fifties, was a unique institution in that, although it never succeeded in its primary goal of building a multi-GeV particle accelerator, it remained in existence for more than ten years, during which the MURA group made many contributions to the science of particle accelerators. Included among these were the invention of fixed field alternating gradient (FFAG) accelerators and spiral sector cyclotrons, an extensive analysis of rf acceleration with particular attention to the consequences of Liouville's theorem, beam stacking, analytic and computational studies of nonlinear orbit theory, studies of collective instabilities, and the first demonstration of practical ways to achieve colliding beams, Although no large FFAG accelerators were ever built, model FFAG accelerators turned out to be excellent devices for the experimental study of accelerator problems because they separate the guide field from the acceleration process. Models were used to study nonlinear resonances, acceleration processes, space charge limits, and beam stacking. Among the last MURA projects was an electron storage ring that became the first machine dedicated exclusively to the production of synchrotron radiation for experiments, a facility which evolved into the highly successful Synchrotron Radiation Center at the University of Wisconsin-Madison.