IPAC2011 - List of Authors (Sato, S.)

Paper	Title	Page
WEPC015	Tuning Methods for HIMAC Multiple-energy Operation	2037
	K. Katagiri, T. Furukawa, Y. Iwata, K. Noda, S. Sato, T. Shirai NIRS, Chiba-shi, Japan K. Mizushima Chiba University, Graduate School of Science and Technology, Chiba, Japan E. Takeshita Gunma University, Heavy-Ion Medical Research Center, Maebashi-Gunma, Japan
	Beam stability of multiple-energy operation at HIMAC synchrotron was improved for the fast raster-scanning irradiation. In order to improve the transverse stability, the working point of the betatron tune was investigated during one operation cycle. The signals were collected from the beam position monitor using a fast data-acquisition unit. The temporal evolution of the horizontal and vertical betatron tune was evaluated by using the short time Fourier transform. Analyzed results showed that variation of the betatron tune in the acceleration interval passed through the 3rd-order coupling resonance line, and it caused undesirable emittance growth. In order to keep the working point within the desirable operating region, the current pattern of the power supplies for the quadrupole magnets was corrected by using the variation of the betatron tune. The experimental results showed that the working point could be successfully stabilized, and the undesirable beam losses could be reduced during the acceleration interval.

THPS071	The HIMAC Beam-intensity Control System for Heavy-ion Scanning	3592
	K. Mizushima Chiba University, Graduate School of Science and Technology, Chiba, Japan T. Furukawa, Y. Iwata, K. Katagiri, K. Noda, S. Sato, T. Shirai NIRS, Chiba-shi, Japan E. Takeshita Gunma University, Heavy-Ion Medical Research Center, Maebashi-Gunma, Japan
	Raster scanning irradiation has been carried out at a HIMAC new treatment facility in NIRS. In order to reduce the difference between prescribed and delivered dose distribution, the accurate beam-intensity control with a low ripple and the fast beam-on/off switching are strongly required. For this purpose, we have developed a new beam-intensity control system using the RF-knockout slow extraction. To keep the beam rate constant, this system controls the transverse RF voltage with the feedback proportional-integral control. In addition, the beam-on/off response was improved by the fast quadrupole magnets and the implementation of the transverse beam preheating method. As a result of the system commissioning, it was verified that this system can modulate the beam-intensity with a low ripple and switch the beam-on/off with quick responses. We will report the result in detail.

THPS072	Commissioning of NIRS Fast Scanning System for Heavy-ion Therapy	3595
	T. Furukawa, T. Inaniwa, K. Katagiri, K. Mizushima, K. Noda, S. Sato, T. Shirai NIRS, Chiba-shi, Japan E. Takeshita Gunma University, Heavy-Ion Medical Research Center, Maebashi-Gunma, Japan
	The commissioning of NIRS fast scanning system was started in September 2010, when the first beam was successfully delivered from the HIMAC synchrotron to the new treatment room. After the fine tuning of the new transport line, the commissioning of the scanning system was carried out as following steps; 1) verification of the beam size, position and intensity stability; 2) verification of beam scanning performance and calibration; 3) verification of beam monitor performance; 4) dose measurement of pencil beams for the beam parameterization in the treatment planning system; and 5) verification of 3D dose conformation. As a result of the commissioning, we verified that the new scanning delivery system can produce an accurate 3D dose distribution for the target volume in combination with the planning software. We will report the commissioning results and the performance of the scanning system.

THPS073	Dosimetric Impact of Multiple Energy Operation in Carbon-ion Radiotherapy	3598
	T. Inaniwa, T. Furukawa, N. Kanematsu, S. Mori, K. Noda, S. Sato, T. Shirai NIRS, Chiba-shi, Japan
	In radiotherapy with a scanned carbon beam, its Bragg peak is placed within the target volume either by inserting the range shifter plates or by changing the beam energy extracted from the synchrotron. The former method (range shifter scanning: RS) is adopted in NIRS while the latter method (active energy scanning: ES) has been used in GSI and HIT. In NIRS, an intermediate method, a combination scanning (CS), is now under consideration where eleven beam energies having the ranges with 30 mm intervals are prepared and used in conjunction with the range shifter plates for slighter range shift. The disadvantages of the RS are the beam spread due to the multiple scattering within the range shifter plates and the production of fragment particles through the nuclear reactions within them. On the other hand, for the ES, severely time-consuming beam commissioning and the expensive devices are required. In this study, we compare these three methods from the viewpoint of dose distributions and the impacts for clinical cases will be discussed.

THPS075	Recent Progress of New Cancer Therapy Facility at HIMAC	3604
	T. Shirai, T. Furukawa, T. Inaniwa, Y. Iwata, K. Katagiri, K. Mizushima, S. Sato, E. Takada, Y. Takei, E. Takeshita NIRS, Chiba-shi, Japan T. Fujimoto, T. Kadowaki, T. Miyoshi, Y. Sano AEC, Chiba, Japan
	Since 1994, the carbon beam treatment has been continued at Heavy Ion Medical Accelerator in Chiba (HIMAC). The total number of patients treated is more than 5,000 in 2010. Based on more than ten years of experience with HIMAC, we have developed new treatment equipments toward adaptive cancer therapy with heavy ion at New Particle Therapy Research Facility in NIRS.

Paper

Title

Page

Tuning Methods for HIMAC Multiple-energy Operation

2037

K. Katagiri, T. Furukawa, Y. Iwata, K. Noda, S. Sato, T. Shirai
NIRS, Chiba-shi, Japan
K. Mizushima
Chiba University, Graduate School of Science and Technology, Chiba, Japan
E. Takeshita
Gunma University, Heavy-Ion Medical Research Center, Maebashi-Gunma, Japan

Beam stability of multiple-energy operation at HIMAC synchrotron was improved for the fast raster-scanning irradiation. In order to improve the transverse stability, the working point of the betatron tune was investigated during one operation cycle. The signals were collected from the beam position monitor using a fast data-acquisition unit. The temporal evolution of the horizontal and vertical betatron tune was evaluated by using the short time Fourier transform. Analyzed results showed that variation of the betatron tune in the acceleration interval passed through the 3rd-order coupling resonance line, and it caused undesirable emittance growth. In order to keep the working point within the desirable operating region, the current pattern of the power supplies for the quadrupole magnets was corrected by using the variation of the betatron tune. The experimental results showed that the working point could be successfully stabilized, and the undesirable beam losses could be reduced during the acceleration interval.

THPS071

The HIMAC Beam-intensity Control System for Heavy-ion Scanning

3592

K. Mizushima
Chiba University, Graduate School of Science and Technology, Chiba, Japan
T. Furukawa, Y. Iwata, K. Katagiri, K. Noda, S. Sato, T. Shirai
NIRS, Chiba-shi, Japan
E. Takeshita
Gunma University, Heavy-Ion Medical Research Center, Maebashi-Gunma, Japan

Raster scanning irradiation has been carried out at a HIMAC new treatment facility in NIRS. In order to reduce the difference between prescribed and delivered dose distribution, the accurate beam-intensity control with a low ripple and the fast beam-on/off switching are strongly required. For this purpose, we have developed a new beam-intensity control system using the RF-knockout slow extraction. To keep the beam rate constant, this system controls the transverse RF voltage with the feedback proportional-integral control. In addition, the beam-on/off response was improved by the fast quadrupole magnets and the implementation of the transverse beam preheating method. As a result of the system commissioning, it was verified that this system can modulate the beam-intensity with a low ripple and switch the beam-on/off with quick responses. We will report the result in detail.

THPS072

Commissioning of NIRS Fast Scanning System for Heavy-ion Therapy

3595

T. Furukawa, T. Inaniwa, K. Katagiri, K. Mizushima, K. Noda, S. Sato, T. Shirai
NIRS, Chiba-shi, Japan
E. Takeshita
Gunma University, Heavy-Ion Medical Research Center, Maebashi-Gunma, Japan

The commissioning of NIRS fast scanning system was started in September 2010, when the first beam was successfully delivered from the HIMAC synchrotron to the new treatment room. After the fine tuning of the new transport line, the commissioning of the scanning system was carried out as following steps; 1) verification of the beam size, position and intensity stability; 2) verification of beam scanning performance and calibration; 3) verification of beam monitor performance; 4) dose measurement of pencil beams for the beam parameterization in the treatment planning system; and 5) verification of 3D dose conformation. As a result of the commissioning, we verified that the new scanning delivery system can produce an accurate 3D dose distribution for the target volume in combination with the planning software. We will report the commissioning results and the performance of the scanning system.

THPS073

Dosimetric Impact of Multiple Energy Operation in Carbon-ion Radiotherapy

3598

T. Inaniwa, T. Furukawa, N. Kanematsu, S. Mori, K. Noda, S. Sato, T. Shirai
NIRS, Chiba-shi, Japan

In radiotherapy with a scanned carbon beam, its Bragg peak is placed within the target volume either by inserting the range shifter plates or by changing the beam energy extracted from the synchrotron. The former method (range shifter scanning: RS) is adopted in NIRS while the latter method (active energy scanning: ES) has been used in GSI and HIT. In NIRS, an intermediate method, a combination scanning (CS), is now under consideration where eleven beam energies having the ranges with 30 mm intervals are prepared and used in conjunction with the range shifter plates for slighter range shift. The disadvantages of the RS are the beam spread due to the multiple scattering within the range shifter plates and the production of fragment particles through the nuclear reactions within them. On the other hand, for the ES, severely time-consuming beam commissioning and the expensive devices are required. In this study, we compare these three methods from the viewpoint of dose distributions and the impacts for clinical cases will be discussed.

THPS075

Recent Progress of New Cancer Therapy Facility at HIMAC

3604

T. Shirai, T. Furukawa, T. Inaniwa, Y. Iwata, K. Katagiri, K. Mizushima, S. Sato, E. Takada, Y. Takei, E. Takeshita
NIRS, Chiba-shi, Japan
T. Fujimoto, T. Kadowaki, T. Miyoshi, Y. Sano
AEC, Chiba, Japan

Since 1994, the carbon beam treatment has been continued at Heavy Ion Medical Accelerator in Chiba (HIMAC). The total number of patients treated is more than 5,000 in 2010. Based on more than ten years of experience with HIMAC, we have developed new treatment equipments toward adaptive cancer therapy with heavy ion at New Particle Therapy Research Facility in NIRS.