Open AccessConcept design of new compact electron cyclotron resonance ion source with permanent magnets for multi-ion radiotherapy
Author(s) -
M. Muramatsu,
Fumihisa Ouchi,
Taku Suzuki,
Katsuyuki Takahashi,
Toshinobu Sasano,
Tadahiro Shiraishi,
S. Nomura,
Nobuaki Takahashi,
Yushi Kato,
Ken Katagiri,
Kota Mizushima,
Yoshiyuki Iwata,
Taku Inaniwa,
A. Kitagawa
Publication year - 2022
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/2244/1/012094
Subject(s) - ion source , ion , neon , electron cyclotron resonance , ion beam , helium , atomic physics , magnet , beam (structure) , ionization , ion gun , materials science , chemistry , physics , optics , argon , organic chemistry , quantum mechanics
The multi-ion radiotherapy with dose distribution and Liner Energy Transfer optimization is being studied at QST. Helium, carbon, oxygen and neon ions are considered as ion species for multi-ion therapy. A basic experiment using these ion beams has been carried out at the HIMAC. For heavy-ion radiotherapy facility, it is desirable to operate with only one ECR ion source with permanent magnets from the viewpoint of cost and maintenance. We considered the operating method with only one ion source for multi-ion radiotherapy. Ionization gases were helium, methane, oxygen, and neon to produce He 2+ , C 4+ , O 6+ and Ne 7+ ions. Requirement values of beam current were 940 μA correspond to He 2+ , 290 μA to C 4+ , 330 μA to O 6+ , and 245 μA to Ne 7+ , respectively. This value was obtained from the number of particles required for the cancer treatment and the transmission efficiency of the accelerator in the HIMAC. We performed some beam tests for design of a new compact ion source with the existing 18 GHz ECR ion source (NIRS-HEC). From the results of the beam tests, we estimate the mirror magnetic field of NIRS-HEC by using POISSON/SUPERFISH code. Then, the structure of the permanent magnets for new ECR ion source is determined so that they reproduce the values of the upstream mirror peak (Binj), B minimum (Bmin) and the downstream mirror peak (Bext) at the NIRS-HEC. The magnetic field of Binj, Bmin and Bext at NIRS-HEC were 1.14 T, 0.475 T and 0.9 T, respectively.