@inproceedings{oai:repo.qst.go.jp:00075603,
 author = {Muramatsu, Masayuki and Kitagawa, Atsushi and Inaniwa, Taku and Iwata, Yoshiyuki and Mizushima, Kota and Muramatsu, Masayuki and Kitagawa, Atsushi and Inaniwa, Taku and Iwata, Yoshiyuki and Mizushima, Kota},
 book = {Proceedings of 23rd International workshop on ECR ion sources (ECRIS2018)},
 month = {Feb},
 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 eA, respectively. We obtained beam current of 482, 151, and 270 eA for He2+, C2+ and O3+ with mixed helium and CO2 gases under the extraction voltage of 27 kV. Beam current of 27 and 15 eA 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.},
 pages = {79--81},
 title = {Production of various ion species by gas pulsing technique for multi ion irradiation at NIRS-HEC ion source},
 year = {2019}
}