736
M. Dohlus et al.
Fig. 11.30 This design of CABOTO (CArbon BOoster for the Therapy in Oncology) features a
150 MeV/u superconducting isochronous cyclotron followed by a 5.7 GHz standing-wave linac
powered by seventeen 12 MW klystrons (courtesy of TERA Foundation)
electric fields larger than 150 MV/m. In parallel an all-linac solution was studied by
L. Picardi and collaborators [99] which has been adopted for the TOP-IMPLART a
proton-therapy facility under development at the Laboratories of Enea, in Frascati,
Italy. The 150 MeV linac will be installed in the IFO Hospital, in Rome.
In the last years various cyclinacs have been designed: for proton therapy a 15-m
long linac could be used to accelerate the protons between 30 MeV and a maximum
of 230 MeV. A second cyclinac design is based on a superconducting cyclotron
that accelerates carbon ions C +6 (and H 2
+ molecules) to 150 MeV/u (Fig. 11.30)
with a 300–400 Hz repetition rate [100]. The linac is subdivided in modules, which
interspaced with permanent magnetic quadruples are so short that the beam energy
can be continuously varied in a couple of milliseconds between the cyclotron energy
and the maximum by varying the output power of the klystrons.
Fixed Field Alternating Gradient (FFAG) accelerators have been proposed as
fast cycling accelerators for hadron therapy since the magnetic fields of the ring
are constant in time—as in a cyclotron—and the frequency of the accelerating
electric field can vary up to 500–1000 Hz. The many bending magnets are arranged
in triplets: the central magnet bends the circulating beam inwards while the two
external ones bend it outwards. During acceleration the orbits maintain the same
oscillating shape but increase in average radius so to remain inside the wide vacuum
chamber and find stronger and stronger deflecting fields. In the recent ‘non scaling’
FFAGs the orbits of increasing radius do not maintain the same shape so that the
full excursion requires bending magnets which are radially smaller than in classical
‘scaling’ FFAGs. It has to be noted that in every case beam extraction at different
energies needs fast kickers [101].
M. Dohlus et al.
Fig. 11.30 This design of CABOTO (CArbon BOoster for the Therapy in Oncology) features a
150 MeV/u superconducting isochronous cyclotron followed by a 5.7 GHz standing-wave linac
powered by seventeen 12 MW klystrons (courtesy of TERA Foundation)
electric fields larger than 150 MV/m. In parallel an all-linac solution was studied by
L. Picardi and collaborators [99] which has been adopted for the TOP-IMPLART a
proton-therapy facility under development at the Laboratories of Enea, in Frascati,
Italy. The 150 MeV linac will be installed in the IFO Hospital, in Rome.
In the last years various cyclinacs have been designed: for proton therapy a 15-m
long linac could be used to accelerate the protons between 30 MeV and a maximum
of 230 MeV. A second cyclinac design is based on a superconducting cyclotron
that accelerates carbon ions C +6 (and H 2
+ molecules) to 150 MeV/u (Fig. 11.30)
with a 300–400 Hz repetition rate [100]. The linac is subdivided in modules, which
interspaced with permanent magnetic quadruples are so short that the beam energy
can be continuously varied in a couple of milliseconds between the cyclotron energy
and the maximum by varying the output power of the klystrons.
Fixed Field Alternating Gradient (FFAG) accelerators have been proposed as
fast cycling accelerators for hadron therapy since the magnetic fields of the ring
are constant in time—as in a cyclotron—and the frequency of the accelerating
electric field can vary up to 500–1000 Hz. The many bending magnets are arranged
in triplets: the central magnet bends the circulating beam inwards while the two
external ones bend it outwards. During acceleration the orbits maintain the same
oscillating shape but increase in average radius so to remain inside the wide vacuum
chamber and find stronger and stronger deflecting fields. In the recent ‘non scaling’
FFAGs the orbits of increasing radius do not maintain the same shape so that the
full excursion requires bending magnets which are radially smaller than in classical
‘scaling’ FFAGs. It has to be noted that in every case beam extraction at different
energies needs fast kickers [101].