Performance of fragment separator with homogeneously thick energy degrader: a highly flexible system for use with degraders in a wide thickness range

A projectile-fragment separator, secondary beam line, has been constructed at RCNP for use with the K = 400 ring cyclotron. Products of the projectile fragmentation reactions are isotopically separated by making use of their energy-loss effect in an energy degrader. Unlike the existing separators of similar kind, a homogeneously thick degrader is used and achromatic focus is achieved by the optics of the magnetic system. The separator was designed so as to possess a high ion-optical flexibility which allows the use of degraders of widely ranged thickness. For commissioning the separator, a detailed experimental analysis of the optics was carried out to realize the design performance, and a prescription to correctly determine the strengths of focusing devices was established. The operational performance of the separator is presented.