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Harisaki S, Onishi K, Hamada K, Takeda T, Okumura K, Omori T, Kubo W, Ishihara M, Kato Y. Improving multipole magnets and background vacuum conditions on electron cyclotron resonance ion sources. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:013308. [PMID: 32012560 DOI: 10.1063/1.5128472] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2019] [Accepted: 12/16/2019] [Indexed: 06/10/2023]
Abstract
Electron cyclotron resonance ion sources (ECRISs) are used in various fields such as accelerator physics, engineering, cancer therapy, and ion engines in the satellite. We are aiming to improve the production of multicharged ions efficiently at the point of view from the length of multipole magnets and vacuum conditions in the ECRIS. The diameter of the connection pipe between the main chamber and diffusion pump was made larger to improve vacuum conductance. Moreover, the length of multipole magnets with the direction along the geometrical axis in the ECRIS was extended. The effects of these improvements are investigated experimentally to measure the pressure in the vacuum chamber, beam intensity, charge state distributions of extracted ion beams, and plasma parameters. The purity of extracted ion beams and magnetic confinement have been enhanced. These results are expected to have positive effects on the production of various species and synthesized ion beams, e.g., production of iron endohedral fullerene in the future experiments in the ECRIS.
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Affiliation(s)
- Shuhei Harisaki
- Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Koji Onishi
- Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Kouta Hamada
- Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Tatsuto Takeda
- Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Kazuki Okumura
- Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Takayuki Omori
- Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Wataru Kubo
- Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Masaki Ishihara
- Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Yushi Kato
- Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
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Wedenberg M, Beltran C, Mairani A, Alber M. Advanced Treatment Planning. Med Phys 2018; 45:e1011-e1023. [PMID: 30421811 DOI: 10.1002/mp.12943] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Revised: 03/22/2018] [Accepted: 04/22/2018] [Indexed: 12/15/2022] Open
Abstract
Treatment planning for protons and heavier ions is adapting technologies originally developed for photon dose optimization, but also has to meet its particular challenges. Since the quality of the applied dose is more sensitive to geometric uncertainties, treatment plan robust optimization has a much more prominent role in particle therapy. This has led to specific planning tools, approaches, and research into new formulations of the robust optimization problems. Tools for solution space navigation and automatic planning are also being adapted to particle therapy. These challenges become even greater when detailed models of relative biological effectiveness (RBE) are included into dose optimization, as is required for heavier ions.
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Affiliation(s)
| | - Chris Beltran
- Division of Medical Physics, Department of Radiation Oncology, Mayo Clinic, Rochester, MN, USA
| | - Andrea Mairani
- Heidelberg Ion Therapy Center (HIT), Heidelberg University Hospital, Heidelberg, Germany.,National Center for Radiation Research in Oncology (NCRO), Heidelberg Institute for Radiation Oncology (HIRO), Heidelberg, Germany.,The National Centre for Oncological Hadrontherapy (CNAO), Pavia, Italy
| | - Markus Alber
- The National Centre for Oncological Hadrontherapy (CNAO), Pavia, Italy.,Section for Medical Physics, Department of Radiation Oncology, Heidelberg University Hospital, Heidelberg, Germany
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Uehara T, Watanabe M, Suzuki H, Furusawa Y, Arano Y. Amino acid transport system - A substrate predicts the therapeutic effects of particle radiotherapy. PLoS One 2017; 12:e0173096. [PMID: 28245294 PMCID: PMC5330493 DOI: 10.1371/journal.pone.0173096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Accepted: 02/15/2017] [Indexed: 11/19/2022] Open
Abstract
L-[methyl-11C]Methionine (11C-Met) is useful for estimating the therapeutic efficacy of particle radiotherapy at early stages of the treatment. Given the short half-life of 11C, the development of longer-lived 18F- and 123I-labeled probes that afford diagnostic information similar to 11C-Met, are being sought. Tumor uptake of 11C-Met is involved in many cellular functions such as amino acid transport System-L, protein synthesis, and transmethylation. Among these processes, since the energy-dependent intracellular functions involved with 11C-Met are more reflective of the radiotherapeutic effects, we evaluated the activity of the amino acid transport System-A as an another energy-dependent cellular function in order to estimate radiotherapeutic effects. In this study, using a carbon-ion beam as the radiation source, the activity of System-A was evaluated by a specific System-A substrate, alpha-[1-14C]-methyl-aminoisobutyric acid (14C-MeAIB). Cellular growth and the accumulation of 14C-MeAIB or 14C-Met were evaluated over time in vitro in cultured human salivary gland (HSG) tumor cells (3-Gy) or in vivo in murine xenografts of HSG tumors (6- or 25-Gy) before and after irradiation with the carbon-ion beam. Post 3-Gy irradiation, in vitro accumulation of 14C-Met and 14C-MeAIB decreased over a 5-day period. In xenografts of HSG tumors in mice, tumor re-growth was observed in vivo on day-10 after a 6-Gy irradiation dose, but no re-growth was detected after the 25-Gy irradiation dose. Consistent with the growth results, the in vivo tumor accumulation of 14C-MeAIB did not decrease after the 6-Gy irradiation dose, whereas a significant decrease was observed after the 25-Gy irradiation dose. These results indicate that the activity of energy dependent System-A transporter may reflect the therapeutic efficacy of carbon-ion radiotherapy and suggests that longer half-life radionuclide-labeled probes for System-A may also provide widely available probes to evaluate the effects of particle radiotherapy on tumors at early stage of the treatment.
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Affiliation(s)
- Tomoya Uehara
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Science, Chiba University, Chiba, Japan
- * E-mail:
| | - Mariko Watanabe
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Science, Chiba University, Chiba, Japan
| | - Hiroyuki Suzuki
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Science, Chiba University, Chiba, Japan
| | - Yoshiya Furusawa
- National Institutes for Quantum and Radiological Science and Technology, National Institute of Radiological Sciences, Chiba, Japan
| | - Yasushi Arano
- Department of Molecular Imaging and Radiotherapy, Graduate School of Pharmaceutical Science, Chiba University, Chiba, Japan
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Nishiokada T, Nagaya T, Hagino S, Otsuka T, Muramatsu M, Sato F, Kitagawa A, Kato Y. Experimental results of superimposing 9.9 GHz extraordinary mode microwaves on 2.45 GHz ECRIS plasma. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:02A714. [PMID: 26931932 DOI: 10.1063/1.4934212] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Efficient production of multicharged ions has been investigated on the tandem-type ECRIS in Osaka University. According to the consideration of the accessibility conditions of microwaves to resonance and cutoff regions, it was suggested that the upper hybrid resonance (UHR) heating contributed to enhancement of ion beam intensity. In order to enhance multicharged ion beams efficiently, injecting higher frequency microwave with extraordinary (X-mode) toward UHR region has been tried. In this study, 2.45 GHz frequency microwaves are used for conventional ECR discharge, and 9.9 GHz frequency microwaves with X-mode are superimposed for UHR heating. The effects of additive microwave injection are investigated experimentally in terms of plasma parameters and electron energy distribution function (EEDF) measured by Langmuir probe and ion beam current. As the results show, it is confirmed that the electrons in the high energy region are affected by 9.9 GHz X-mode microwave injection from the detailed analysis of EEDF.
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Affiliation(s)
- Takuya Nishiokada
- Division of Electrical, Electronic, and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Tomoki Nagaya
- Division of Electrical, Electronic, and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Shogo Hagino
- Division of Electrical, Electronic, and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Takuro Otsuka
- Division of Electrical, Electronic, and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Masayuki Muramatsu
- National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-855, Japan
| | - Fuminobu Sato
- Division of Electrical, Electronic, and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Atsushi Kitagawa
- National Institute of Radiological Sciences (NIRS), 4-9-1 Anagawa, Inage-ku, Chiba-shi, Chiba 263-855, Japan
| | - Yushi Kato
- Division of Electrical, Electronic, and Information Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
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Biri S, Kitagawa A, Muramatsu M, Drentje AG, Rácz R, Yano K, Kato Y, Sasaki N, Takasugi W. Two-frequency heating technique at the 18 GHz electron cyclotron resonance ion source of the National Institute of Radiological Sciences. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2014; 85:02A931. [PMID: 24593510 DOI: 10.1063/1.4829735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The two-frequency heating technique was studied to increase the beam intensities of highly charged ions provided by the high-voltage extraction configuration (HEC) ion source at the National Institute of Radiological Sciences (NIRS). The observed dependences on microwave power and frequency suggested that this technique improved plasma stability but it required precise frequency tuning and more microwave power than was available before 2013. Recently, a new, high-power (1200 W) wide band-width (17.1-18.5 GHz) travelling-wave-tube amplifier (TWTA) was installed. After some single tests with klystron and TWT amplifiers the simultaneous injection of the two microwaves has been successfully realized. The dependence of highly charged ions (HCI) currents on the superposed microwave power was studied by changing only the output power of one of the two amplifiers, alternatively. While operating the klystron on its fixed 18.0 GHz, the frequency of the TWTA was swept within its full limits (17.1-18.5 GHz), and the effect of this frequency on the HCI-production rate was examined under several operation conditions. As an overall result, new beam records of highly charged argon, krypton, and xenon beams were obtained at the NIRS-HEC ion source by this high-power two-frequency operation mode.
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Affiliation(s)
- S Biri
- National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - A Kitagawa
- National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - M Muramatsu
- National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - A G Drentje
- National Institute of Radiological Science (NIRS), 4-9-1 Anagawa, Inage, Chiba 263-8555, Japan
| | - R Rácz
- Institute for Nuclear Research (ATOMKI), H-4026 Debrecen, Bem tér 18/c, Hungary
| | - K Yano
- Graduated School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - Y Kato
- Graduated School of Engineering, Osaka University, 2-1 Yamada-oka, Suita-shi, Osaka 565-0871, Japan
| | - N Sasaki
- Accelerator Engineering Corporation (AEC), Inage, Chiba 263-0043, Japan
| | - W Takasugi
- Accelerator Engineering Corporation (AEC), Inage, Chiba 263-0043, Japan
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