IPAC2011 - List of Authors (Sugai, I.)

Paper	Title	Page
TUPS086	Ultra-high Resolution Observation Device for Carbon Stripper Foil	1740
	Y. Takeda, Y. Irie, I. Sugai KEK, Ibaraki, Japan
	To observe a growth process of a pinhole on a HBC-foil due to beam irradiation, an up to 10 um of device for ultra-high resolution observation is needed. For the environment where we use the device for observation is so severe as under high radiation and in vacuum, there is no device available for long-time observation. Then, we designed and created a wholly new method based system which enables constant observation by ultra-high resolution even under high radiation environment. We attempted several experiments, compared materials usable under radiation environment, checked up various optical systems which enables high resolution, and finally developed the best method. As a result, we successfully invented an ultra-high resolution observation device available for monitoring an object about 8 meters distant by 8.3um resolution.

THPS036	Development of Thin NCS-foils by N+ Ion Beam Sputtering and Their Characteristics	3499
	I. Sugai, H. Kawakami, M. Oyaizu, Y. Takeda KEK, Ibaraki, Japan T. Hattori, K.K. Kawasaki RLNR, Tokyo, Japan
	We have developed thin Nitride Carbon Stripper foils (NCS-foil) with a higher nitrogen content by ion beam sputtering　method with reactive nitrogen gas. Such NCS-foils have been demonstrated that the foils in range of 10^-25 ug/m2 have shown long-lifetime as stripper foil against high intensity heavy ion beam bombardment. From the results, we found that the nitrogen element in the carbon foils plays very important role of the foil lifetime. Therefore, in order to investigate further influence of the lifetime on the nitrogen amount in the NCS-foils, we measured the sputtering yield at the different sputtering angles and carbon source materials. We also measured the ratio of nitrogen in carbon foil made at the different sputtering angles, target materials and the sputtering voltages of 4-15 kV by means of RBS method. The foil-lifetime made in above different conditions was measured with a 3.2 MeV Ne⁺ ion beam. The lifetime does not essentially depend on the sputtering angles and the target materials, and the maximum and average lifetimes showed 240 and 40 times longer than that of the CM-best foils.

THPS037	Performance Characteristics of HBC-foils by 650 KeV H⁻ and DC High Intensity Ion Beam Irradiation	3502
	I. Sugai, Y. Irie, H. Kawakami, M. Oyaizu, A. Takagi, Y. Takeda KEK, Ibaraki, Japan M. Kinsho, Y. Yamazaki, M. Yoshimoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	Newly developed Hybrid type Boron mixed Carbon stripper foils (HBC-stripper foil) are extensively used for not only J-PARC, for but also LANL-PSR since September of 2007. In order to know further characteristics of the HBC-stripper foils, we measured following parameters; foil lifetimes, thickness reduction, uniformity before and after beam irradiation and foil shrinkage, using 3.2 MeV Ne⁺ DC beam from TIT-Van de Grraff and 650 keV DC proton beam at KEK Cock-Croft accelerators, which are almost the same energy deposition as well as the J-PARC. We also investigated sputtering yield by hydrogen ion beam, thermal conductivity, weight change in heating and density of the HBC-stripper foils. We compared these values with other tested carbon stripper foils such as commercially available carbon foils (CM-foil), synthetic diamond (DM-foil) and nano-tube carbon foils (NTC-foil). Through these experiments, the　HBC-stripper foils showed superior performance characteristics, in especially, on the lifetime at temperature higher than 1800K compared with other tested CM-, DM- and NTC-foils.

THPS040	Measurement of the Stripping Efficiency for HBC Stripper Foil in the 3-GeV RCS of J-PARC	3511
	P.K. Saha, H. Harada, S. Hatakeyama, H. Hotchi, M. Kinsho, Y. Yamazaki, M. Yoshimoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan Y. Irie, I. Sugai KEK, Ibaraki, Japan
	We have carried out experimental measurement of the stripping efficiency for the newly developed HBC (Hybrid type Boron doped Carbon) stripper foils. The HBC foil is used for charge-exchange injection in the RCS (Rapid Cycling Synchrotron) of J-PARC (Japan Proton Accelerator Research Complex) and plays an important role for the RCS operation. We have developed a rather simple but very precise method using which stripping efficiencies for several HBC foils were determined accurately. Importance of knowing an accurate stripping efficiency so as to determine a realistic stripper foil for the RCS operation will be discussed.

Paper

Title

Page

Ultra-high Resolution Observation Device for Carbon Stripper Foil

1740

Y. Takeda, Y. Irie, I. Sugai
KEK, Ibaraki, Japan

To observe a growth process of a pinhole on a HBC-foil due to beam irradiation, an up to 10 um of device for ultra-high resolution observation is needed. For the environment where we use the device for observation is so severe as under high radiation and in vacuum, there is no device available for long-time observation. Then, we designed and created a wholly new method based system which enables constant observation by ultra-high resolution even under high radiation environment. We attempted several experiments, compared materials usable under radiation environment, checked up various optical systems which enables high resolution, and finally developed the best method. As a result, we successfully invented an ultra-high resolution observation device available for monitoring an object about 8 meters distant by 8.3um resolution.

THPS036

Development of Thin NCS-foils by N+ Ion Beam Sputtering and Their Characteristics

3499

I. Sugai, H. Kawakami, M. Oyaizu, Y. Takeda
KEK, Ibaraki, Japan
T. Hattori, K.K. Kawasaki
RLNR, Tokyo, Japan

We have developed thin Nitride Carbon Stripper foils (NCS-foil) with a higher nitrogen content by ion beam sputtering　method with reactive nitrogen gas. Such NCS-foils have been demonstrated that the foils in range of 10^-25 ug/m2 have shown long-lifetime as stripper foil against high intensity heavy ion beam bombardment. From the results, we found that the nitrogen element in the carbon foils plays very important role of the foil lifetime. Therefore, in order to investigate further influence of the lifetime on the nitrogen amount in the NCS-foils, we measured the sputtering yield at the different sputtering angles and carbon source materials. We also measured the ratio of nitrogen in carbon foil made at the different sputtering angles, target materials and the sputtering voltages of 4-15 kV by means of RBS method. The foil-lifetime made in above different conditions was measured with a 3.2 MeV Ne⁺ ion beam. The lifetime does not essentially depend on the sputtering angles and the target materials, and the maximum and average lifetimes showed 240 and 40 times longer than that of the CM-best foils.

THPS037

Performance Characteristics of HBC-foils by 650 KeV H⁻ and DC High Intensity Ion Beam Irradiation

3502

I. Sugai, Y. Irie, H. Kawakami, M. Oyaizu, A. Takagi, Y. Takeda
KEK, Ibaraki, Japan
M. Kinsho, Y. Yamazaki, M. Yoshimoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

Newly developed Hybrid type Boron mixed Carbon stripper foils (HBC-stripper foil) are extensively used for not only J-PARC, for but also LANL-PSR since September of 2007. In order to know further characteristics of the HBC-stripper foils, we measured following parameters; foil lifetimes, thickness reduction, uniformity before and after beam irradiation and foil shrinkage, using 3.2 MeV Ne⁺ DC beam from TIT-Van de Grraff and 650 keV DC proton beam at KEK Cock-Croft accelerators, which are almost the same energy deposition as well as the J-PARC. We also investigated sputtering yield by hydrogen ion beam, thermal conductivity, weight change in heating and density of the HBC-stripper foils. We compared these values with other tested carbon stripper foils such as commercially available carbon foils (CM-foil), synthetic diamond (DM-foil) and nano-tube carbon foils (NTC-foil). Through these experiments, the　HBC-stripper foils showed superior performance characteristics, in especially, on the lifetime at temperature higher than 1800K compared with other tested CM-, DM- and NTC-foils.

THPS040

Measurement of the Stripping Efficiency for HBC Stripper Foil in the 3-GeV RCS of J-PARC

3511

P.K. Saha, H. Harada, S. Hatakeyama, H. Hotchi, M. Kinsho, Y. Yamazaki, M. Yoshimoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
Y. Irie, I. Sugai
KEK, Ibaraki, Japan

We have carried out experimental measurement of the stripping efficiency for the newly developed HBC (Hybrid type Boron doped Carbon) stripper foils. The HBC foil is used for charge-exchange injection in the RCS (Rapid Cycling Synchrotron) of J-PARC (Japan Proton Accelerator Research Complex) and plays an important role for the RCS operation. We have developed a rather simple but very precise method using which stripping efficiencies for several HBC foils were determined accurately. Importance of knowing an accurate stripping efficiency so as to determine a realistic stripper foil for the RCS operation will be discussed.