@inproceedings{oai:repo.qst.go.jp:00083470,
 author = {Masayuki, Muramatsu and Fumihisa, Ouchi(AEC) and Taku, Suzuki(AEC) and Katsuyuki, Takahashi(AEC) and Toshinobu, Sasano(AEC) and Tadahiro, Shiraishi(AEC) and Shinji, Nomura(SHI) and Nobuaki, Takahashi(SHI) and Yushi, Kato(Osaka Univ.) and Ken, Katagiri and Kota, Mizushima and Taku, Inaniwa and Atsushi, Kitagawa and Masayuki, Muramatsu and Ken, Katagiri and Kota, Mizushima and Taku, Inaniwa and Atsushi, Kitagawa},
 book = {The 19the International Conference on Ion Sources (ICIS2021)},
 month = {Sep},
 note = {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. We considered the operating method with only one ion source for multi-ion radiotherapy. Ionization gases were helium, methane, oxygen, and neon to produce He2+, C4+, O6+ and Ne7+ ions. Requirement values of beam current were 940 µA correspond to He2+, 290 µA to C4+, 330 µA to O6+, and 245 µA to Ne7+, 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.
We will describe about the beam tests with the NIRS-HEC and design of the new compact ECR ion source.},
 title = {Concept design of new compact electron cyclotron resonance ion source with permanent magnets for multi-ion radiotherapy.},
 year = {2021}
}