FFAG Nonscaling FFAGs for Hadron Therapy C. Johnstone, Fermilab FFAG08 Sept 1-5, 2008 University of Manchester Manchester, U.K. Fermilab

FFAG Advances in Medical FFAG accelerators Scaling FFAGs – primarily under development in Japan and recently France Nonscaling FFAGs –Linear-field FFAGs International effort (EMMA ) –Tune-stablized, linear-field FFAG Developed at Fermilab with collaborative design support from TRIUMF and more recently John Adams Institute, Oxford. PAC awarded a Phase I, F. Mills, MSU (Makino and Berz), TRIUMF (Koscielniak), U of Riverside, (Snopok), CRADA with Fermilab (Johnstone and Kashikhin) Fermilab

FFAG Goals of FFAG designs for Medical Accelerators Ultimate design consistent with carbon therapy –Preliminary lattices capable of 400 MeV for protons mm-mr normalized acceptance – not yet optimized Small footprint: ~40m normal conducting, 20 m superconducting (protons) –Synchrotron-like features Variable extraction energy –Resonant or kicker extraction Low losses and component activation Multiple extraction points – multiple treatment areas –Cyclotron-like features High current output Ease of operation – no pulsed components or supplies Fermilab

FFAG Approach : Apply an edge contour to a linear field nonscaling FFAG Linear edge Variational edge Fermilab

FFAG Effect of an edge contour on a nonscaling FFAG Linear-field gradients Linear-gradient + constant edge angle Linear grad+edge contour Fermilab

FFAG Components and Cell Parameters Magnet widths Drift vs. Momentum Field vs Momentum Fermilab

FFAG Ring parameters of tune-stabilized nonscaling FFAG lattice* Circumference30m (4.77m radius) Number of cell9 Cell MeV Length of straight section m Horizontal aperture (QF)~0.6 m (145 MeV/c – 730 MeV/c) ~0.65 m (100 MeV/c – 730 MeV/c) Energy range/momentum5-10 – 250MeV Tune/cell 0.25( H ) 0.25 ( V ) Max field1.5 T (on “F” extraction orbit) Field Gradient-0.49 T/m (QD), 1.8 T/m (QF) Fermilab

FFAG Conclusions Factor of 5-7 in momentum with stable tune has been achieved with a linear gradient and an edge contour. Magnet designs are presently underway Implementation in ZGOUBI and COSY and full tracking and optimization next Fermilab

FFAG Summary of Nonscaling FFAG status and progress Simultaneous multiple sources and injection port Multiple extraction ports Slow or fast resonance or kicker based extraction –resonance extraction has been demonstrated in simulations Variable energy to ~50% of extraction energy – no use of degraders Preliminary magnet designs CRADA established with Fermilab Fermilab

FFAG FFAGs – General Over 30 scaling and nonscaling FFAGs are under design or construction. Applications include –Accelerator Driven Subcritical Reactor –Boron Neutron Capture Therapy –Accelerator-based Neutron Source Emittance/Energy Recovery with Internal Target (ERIT) The first nonscaling FFAG prototype for rapid acceleration (EMMA) is being built at Daresbury Laboratory, U.K. A medical nonscaling FFAG accelerator (PAMELA) is under study in the U.K. Fermilab