@misc{oai:repo.qst.go.jp:00072976,
 author = {Muramatsu, Masayuki and Kitagawa, Atsushi and Ouchi, Fumihisa and Sasano, Toshinobu and Shiraishi, Tadahiro and Suzuki, Taku and Takahashi, Katsuyuki and Inaniwa, Taku and Iwata, Yoshiyuki and Mizushima, Kota and 村松 正幸 and 北川 敦志 and 大内 章央 and 白石 直浩 and 稲庭 拓 and 岩田 佳之 and 水島 康太},
 month = {Sep},
 note = {High-energy carbon-ion radiotherapy is being carried out at Heavy Ion Medical Accelerator in Chiba (HIMAC). Over 11000 cancer patients have been treated with carbon beams having energies of between 56-430 MeV/u since 1994. At present, multi ion irradiation method by various ion species is being studied for optimization of LET and dose distribution. An ion source has to produce the helium, carbon, oxygen and neon at pulse by pulse for this method. Requirement currents for He2+, C2+, O3+ and Ne4+ are 500, 150, 230 and 300 euA, respectively. We obtained beam current of 482, 151, and 270 euA for He2+, C2+ and O3+ with mixed helium and CO2 gases under the extraction voltage of 27 kV. Beam current of 27 and 15 euA for C5+ and O7+ ions were also obtained in this time. He2+ beam include full striped ion such as C6+, N7+ and O8+. We have to increase the purity of He2+ beam. The gas feed system was modified for making pulsed gas by using a solenoid valve for switching different gas. Some experimental results of various ion productions will be described., 23rd International workshop on ECR ion sources (ECRIS2018)},
 title = {Production of various ion species by gas pulsing technique for multi ion irradiation at NIRS-HEC ion source},
 year = {2018}
}