FFAGs as Accelerators and Beam Delivery Devices for Ion Cancer Therapy

Abstract

First, a review is given of fixed field alternating gradient (FFAG) accelerators, presenting a bit of their history and basic concepts. Special attention is paid to the concept of scaling (S-FFAG) and nonscaling (NS-FFAG) FFAGs. This notation is used only in the NS-FFAG part of the article. A discussion is then provided on operating FFAGs. A presentation is made of the designs being considered for S-FFAGs. A bit more is said about the concept of the NS-FFAG and a resonance crossing problem resulting from designs of the NS-FFAGs. A beam delivery system (gantry) employing the NS-FFAG concept is presented after that and, finally, future plans and R&D requirements are put forward.