| Paper | Title | Page |
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| TUOAFI01 | Development for New Carbon Cancer-therapy Facility and Future Plan of HIMAC | 955 |
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| The first clinical trial with carbon beams generated from the HIMAC was conducted in June 1994. The total number of patients treated is now in excess of 2500 as of December 2005. Based on our 10 years of experience with the HIMAC, we have proposed a new carbon-ion therapy facility for widespread use in Japan. The key technologies of the accelerator and irradiation systems for the new facility have been developed since April 2004. The new carbon-therapy facility will be constructed at Gunma University from April 2006. As our future plan for the HIMAC, further, a new treatment facility will be constructed at NIRS from April 2006. The design work has already been initiated and will lead to the further development of the therapy with the HIMAC. The facility is connected with the HIMAC accelerator complex and has two treatment rooms with horizontal and a vertical beam-delivery systems and one room with a rotating gantry. We will report the development for new carbon therapy facility and the design study for new treatment facility with the HIMAC. | ||
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Transparencies | |
| WEPCH167 | Study of Scatterer Method to Compensate Asymmetric Distribution of Slowly Extracted Beam at HIMAC Synchrotron | 2322 |
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| In the medical use of the ion beam, the following characteristics of the beam are preferred: 1) Symmetric Gaussian beam profile is convenient for the scanning irradiation. 2) In the rotating gantry system, the symmetric beam condition can realize no-correlation between the beam profiles and the rotation angles of the gantry. However, the slowly extracted beam has asymmetric distribution in the phase-space and a difference between the horizontal emittance and vertical one. Thus, we have proposed the thin scatterer method to compensate the phase-space distribution of the slowly extracted beam, although the emittance is enlarged by scattering. As a result of particle tracking and experiment, it was verified that the asymmetric distribution was compensated by very small scattering angle. It was also simulated that this scatterer method can realize the symmetric beam condition for the rotating gantry. In this paper, these results of asymmetry compensation for the slow-extraction at HIMAC is presented. | ||
| WEPCH168 | Development toward Turn-key Beam Delivery for Therapeutic Operation at HIMAC | 2325 |
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| Since 1994, more than 2500 cancer patients have been treated by carbon ion beam at HIMAC. To increase the number of patients per day, we have studied the reproducibility of the beam quality, such as the position, profile and intensity, during the operation. For this purpose, the accelerator needs high reproducibility to minimize the beam tuning time with more flexible scheme. Further, the irradiation system and the accelerator need to ensure dose uniformity. As a result of this study, it was found that a slight change of the magnetic field in the transport line would not affect the beam quality. However, a slight change of the horizontal tune strongly affects the beam quality because of a resonant slow-extraction. In this paper, we report about our investigation and present result of the development. | ||
| WEPCH169 | Alternating Phase Focused IH-DTL for Heavy-ion Medical Accelerators | 2328 |
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Tumor therapy using HIMAC has been performed at NIRS since June 1994. With the successful clinical results over more than ten years, a number of projects to construct these complexes have been proposed over the world. Since existing heavy-ion linacs are large in size, the development of compact linacs would play a key role in designing compact and cost-effective complexes. Therefore, we developed an injector system consisting of RFQ and Interdigital H-mode (IH) DTL having the frequency of 200 MHz. The injector system can accelerate carbon ions up to 4.0 AMeV. For the beam focusing of IH-DTL, the method of Alternating Phase Focusing (APF) was employed. With the IH structure and rather high frequency, the cavity size is compact; the radius is 0.4 m, and lengths of RFQ and IH-DTL are 2.5m and 3.5m respectively. The fabrication of RFQ was completed, and we succeeded to accelerate carbon ions with satisfactory performances. For IH-DTL, the full-scale model was first fabricated. With the encouraging result* of its electric field measurement, we constructed IH-DTL and beam acceleration tests will be performed in March 2006. We will present the performances of the entire injector system.
*Y. Iwata et al., Nucl Instr. & Meth in Phys. Res. A (submitted). |
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| WEPCH170 | Development of Intensity Control System with RF-knockout Extraction at the HIMAC Synchrotron | 2331 |
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| We have developed a dynamic intensity control system toward scanning irradiation at the HIMAC Synchrotron. In this system, for controlling the spill structure and intensities of the beams extracted from the synchrotron, the amplitude of the RF-knockout is controlled with the response of 10 kHz. Its amplitude modulation (AM) function is generated based on an analytical one-dimensional model of the RF-knockout slow-extraction. In this paper, we describe the system for controlling amplitude modulation including feedback and the experimental result. |