A dual 6T persistent-mode SC solenoid ion-optical system for radioactive nuclear beam research

A unique ion-optical system for the production of high-intensity, short-liv ed radioactive nuclear beams has been designed, constructed and put into op eration at the Nuclear Structure Laboratory at the University of Notre Dame as a joint project between the University of Michigan and NSL-UND. The sys tem consists of a matched in-line pair of large-bore (30 cm) 6T superconduc tivity solenoid magnets which act as high-acceptance collectors and magneti c filters of secondary radioactive nuclear beam (RNB) products, The latter are brought to a focus on a secondary target and nuclear reactions using th e RNB studied. These are primarily reactions of interest in Big-Bang nucleo synthesis and stellar helium burning and involve the production of (6)EIe,B e-7,B-8 and similar beams. A number of unique features were incorporated in the magnet design to permit use as a precise ion optical device in the RNB mode. To our knowledge this is the only large-scale in-beam ion-optical sy stem to operate primarily in persistent made, A similar device will also be built at the University of Sao Paulo for RNB research.