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Usui, Aya; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Kitano, Toshihiko*; Takayama, Terumitsu*; Orimo, Takao*; Kanai, Shinji*; Aoki, Yuki*; Hashizume, Masashi*; et al.
Dai-28-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.117 - 119, 2015/12
no abstracts in English
Usui, Aya; Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Kitano, Toshihiko*; Takayama, Terumitsu*; Orimo, Takao*; Kanai, Shinji*; Aoki, Yuki*; et al.
Dai-27-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.118 - 121, 2015/03
no abstracts in English
Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Usui, Aya; Saito, Yuichi; Ishii, Yasuyuki; Sato, Takahiro; Okubo, Takeru; Nara, Takayuki; et al.
JAEA-Review 2013-059, JAEA Takasaki Annual Report 2012, P. 179, 2014/03
Three electrostatic accelerators at TIARA were operated on schedule in fiscal year 2012 except changing its schedule by cancellations of users. The yearly operation time of the 3 MV tandem accelerator, the 400 kV ion implanter and the 3MV single-ended accelerator were in the same levels as the ordinary one, whose operation time totaled to 2,073, 1,847 and 2,389 hours, respectively. The tandem accelerator had no trouble, whereas the ion implanter and the single-ended accelerator stopped by any troubles for one day and four days, respectively. The molecular ion beam of helium hydride was generated by the ion implanter, because the users required irradiation of several cluster ions in order to study the effect of irradiation. As a result, its intensity of beam was 50 nA at 200 kV. The ion beam of tungsten (W) at 15 MeV was accelerated by the tandem accelerator, whose intensity was 20 nA at charge state of 4+, because of the request from a researcher in the field of nuclear fusion.
Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Usui, Aya; Kitano, Toshihiko*; Takayama, Terumitsu*; Orimo, Takao*; Kanai, Shinji*; Aoki, Yuki*; et al.
Dai-26-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.79 - 81, 2013/07
Three electrostatic accelerators at TIARA were operated on schedule in fiscal year 2012 except changing its schedule by cancellations of users. The yearly operation time of the 3MV tandem accelerator, the 400 kV ion implanter and the 3 MV single-ended accelerator were in the same levels as the ordinary one, whose operation time totaled to 2,073, 1,847 and 2,389 hours, respectively. The tandem accelerator had no trouble, whereas the ion implanter and the single-ended accelerator stopped by any troubles for one day and four days, respectively. The ion implanter generated molecular ion beam of helium hydride by using the Freeman type ion source, because of the request from the user. As a result, its intensity of beam was 50 nA at 200 kV.
Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Saito, Yuichi; Ishii, Yasuyuki; Sato, Takahiro; Okubo, Takeru; Nara, Takayuki; Kitano, Toshihiko*; et al.
JAEA-Review 2012-046, JAEA Takasaki Annual Report 2011, P. 173, 2013/01
The three electrostatic accelerators at the TIARA had no mechanical damage when the Tohoku earthquake happened on March 11, 2011. But, they could not be operated during April, due to the influence of planned power outage by TEPCO. These accelerators additionally operated on Saturday for ten days in order to compensate for the lost experiment time. As a result, the yearly operation time had kept the same level as the ordinary one. The ion beam of erbium (Er) with 11.7MeV was accelerated newly by the tandem accelerator, whose intensity was 20nA at charge state of 3+. The sequential generation/irradiation of two different kinds of fullerene ions was achieved at the ion implanter by a mixed powder method without exchange of the Freeman type ion source by the user's request.
Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Saito, Yuichi; Ishii, Yasuyuki; Sato, Takahiro; Okubo, Takeru; Nara, Takayuki; Kitano, Toshihiko*; et al.
Dai-7-Kai Takasaki Oyo Kenkyu Shimpojiumu Yoshishu, P. 119, 2012/10
The three electrostatic accelerators at TIARA had no damage when the Tohoku earthquake happened on March 11, 2011. But, they could not be operated until end of April, due to the influence of planned power outage and keep out into the controlled area for radiation. These accelerators additionally operated on Saturday for twelve days in order to compensate for the lost experiment time. Therefore, the yearly operation time had kept the same level as the ordinary one. The tandem accelerator has stopped leakage of the SF gas from the base flange on the tank by the Viton gasket of rectangular cross section at the new type.
Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Kitano, Toshihiko*; Takayama, Terumitsu*; Orimo, Takao*; Kanai, Shinji*; Aoki, Yuki*; Yamada, Naoto*; et al.
Dai-25-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.64 - 66, 2012/07
The three electrostatic accelerators at the TIARA had no damage when the Tohoku earthquake happened on March 11, 2011. But, they could not be operated until end of April, due to the influence of planned power outage and keep out into the controlled area for radiation. These accelerators additionally operated on Saturday for twelve days in order to compensate for the lost experiment time. Therefore, the yearly operation time had kept the same level as the ordinary one. The tandem accelerator has stopped leakage of the SF gas from the base flange on the tank by the Viton gasket of rectangular cross section at the new type. The ion implanter could generate two kinds of fullerene ions by a mixed material of ions and a controlled temperature of the oven without exchange of ion source.
Agematsu, Takashi; Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Saito, Yuichi; Ishii, Yasuyuki; Sato, Takahiro; Okubo, Takeru; Yokota, Wataru; et al.
JAEA-Review 2011-043, JAEA Takasaki Annual Report 2010, P. 173, 2012/01
Three electrostatic accelerators of TIARA were operated smoothly in FY 2010, and all the planned experiments were carried out except those canceled by users or the impact of Great East Japan Earthquake on March 11, 2011. On the other hand, Saturday operation for experiments was carried out after October on the Global Nuclear-Human Resource Development Initiative. The yearly operation time of the tandem accelerator, the single-ended accelerator and the ion implanter amounted to 2116, 2367 and 1800 hours, respectively, which were similar to those of usual years. Regarding the single-ended accelerator, the generator in the high-voltage terminal failed and was replaced with new one. A switching magnet was installed for a new branch beam line of the ion implanter. As to the tandem accelerator, In ion was generated and accelerated at intensity of 500 nA.
Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Agematsu, Takashi; Kitano, Toshihiko*; Takayama, Terumitsu*; Orimo, Takao*; Kanai, Shinji*; Aoki, Yuki*; et al.
Dai-24-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.125 - 128, 2011/07
The yearly operation time of three electrostatic accelerators at TIARA of Japan Atomic Energy Agency is keeping the same level since 2000, the tandem accelerator, the ion implanter and the single-ended accelerator amounted to about 2000, 1900 and 2500 hours, respectively. Three electrostatic accelerators did not have damage when the Tohoku Earthquake occurred on March 11, 2011. However, these accelerators were not able to operate during the planned power outage by Tokyo Electric Power Company (TEPCO). The tandem accelerator accelerated ion beam of In, which gave intensity of 500nA with stability. Additionally, the ion implanter generated maximum 400nA at ion beam of Gd, which was used in experiments for the users.
Agematsu, Takashi; Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Saito, Yuichi; Ishii, Yasuyuki; Sato, Takahiro; Okubo, Takeru; Yokota, Wataru; et al.
JAEA-Review 2010-065, JAEA Takasaki Annual Report 2009, P. 181, 2011/01
Three electrostatic accelerators of TIARA were operated smoothly in FY 2009, and all the planned experiments were carried out except those canceled by users. The yearly operation time of the tandem accelerator, the single-ended accelerator and the ion implanter amounted to 2100, 2416 and 1866 hours, respectively. Regarding the single-ended accelerator, the radio frequency oscillator of the ion source mounted in high-voltage terminal and the sequencer for control of the SB beam line failed, and they were replaced. The oven controller of Freeman ion source of the ion implanter was renewed. As to the tandem accelerator, Mn ion was successfully generated and accelerated with intensity of 150 nA.
Chiba, Atsuya; Uno, Sadanori; Yamada, Keisuke; Yokoyama, Akihito; Agematsu, Takashi; Yokota, Wataru; Kitano, Toshihiko*; Takayama, Terumitsu*; Kanai, Shinji*; Orimo, Takao*; et al.
Dai-23-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.119 - 122, 2010/11
Operation times of each accelerator are keeping the same level as in recent 10 years, Tandem accelerator, Single-ended and Ion implanter amounted to about 2,000, 2,500 and 1,900 hours, respectively. In the last fiscal year, we succeeded in maintaining the terminal voltage of the tandem accelerator to high stability for long periods by exchanging the material of a corona-probe needle to the tungsten (NPS Co.). In the ion-implanter, the oven control system equipped with the Freeman ion source was renewed. There was no trouble to affect on the machine-time in the last fiscal year, so the all planned experiments were carried out.
Chiba, Atsuya; Uno, Sadanori; Yamada, Keisuke; Yokoyama, Akihito; Agematsu, Takashi; Kitano, Toshihiko*; Takayama, Terumitsu*; Orimo, Takao*; Koka, Masashi*; Aoki, Yuki*; et al.
Dai-22-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.104 - 106, 2010/01
no abstracts in English
Agematsu, Takashi; Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Saito, Yuichi; Ishii, Yasuyuki; Sato, Takahiro; Okubo, Takeru; Yokota, Wataru; et al.
JAEA-Review 2009-041, JAEA Takasaki Annual Report 2008, P. 175, 2009/12
Three electrostatic accelerators of TIARA were operated smoothly in FY 2008, and all the planned experiments were carried out except those canceled by users. The yearly operation time of the tandem accelerator, the single-ended accelerator and the ion implanter amounted to 2009, 2426 and 1882 hours, respectively. Regarding the tandem accelerator, the control system was renewed, and the unstable acceleration voltage caused by mechanical vibration reduced by adjusting the driving mechanism of the pellet chains. The SF gas for the single-ended accelerator was purified, and its storage tank was repainted. As to the ion implanter, Bi ion, which was requested by users, was successfully generated and accelerated with intensity of 0.5A.
Hayashi, Takao; Tobita, Kenji; Nakamori, Yuko*; Orimo, Shinichi*
Journal of Nuclear Materials, 386-388, p.119 - 121, 2009/04
Times Cited Count:83 Percentile:98.21(Materials Science, Multidisciplinary)Neutron transport calculations have been carried out to assess the capability of zirconium borohydride (Zr(BH)) and zirconium hydride (ZrH) as advanced shield materials, because excellent shields can be used to protect outer structural materials from serious activation. The neutron shielding capability of Zr(BH) is lower than ZrH, even though the hydrogen density of Zr(BH) is slightly higher than that of ZrH. High-Z atoms are effective in neutron shielding as well as hydrogen atoms. The combination of steel and Zr(BH) can improve the neutron shielding capability. The combinations of (Zr(BH) + F82H) and (ZrH + F82H) can reduce the thickness of the shield by 6.5% and 19% compared to (water + F82H), respectively. The neutron flux for Zr(BH) is drastically reduced in the range of neutron energy below 100 eV compared to other materials, due to the effect of boron, which can lead to a reduction of radwaste from fusion reactors.
Yamada, Keisuke; Okoshi, Kiyonori; Saito, Yuichi; Orimo, Takao*; Omae, Akiomi*; Yamada, Naoto*; Mizuhashi, Kiyoshi
JAEA-Technology 2008-090, 95 Pages, 2009/03
The 400 kV ion implanter at the Takasaki Ion Accelerators for Advanced Radiation Application facility (TIARA) provides ion beams for various experiments of research and development (R&D's) mainly on materials science and biotechnology using Freeman ion sources. Two methods of ionization are generally used to a Freeman ion source. In one method, a sample gas is directly fed to the plasma chamber, and in the other, vapor of a solid material having high vapor pressure is vaporized by an oven and fed. Those methods, however, can supply limited number of ion species of those required from various R&D's. We have developed new methods available to materials which are difficult to vaporize by an oven: the disc method for high melting point materials, the SF plasma method for high melting point and low vapor pressure materials, the filament method for metals with melting point higher than 2400 C, and one of them is chosen according to the nature of a material. Forty four ion species from hydrogen to bismuth are generated by using the Freeman ion sources to date. Furthermore, a small ECR (electron cyclotron resonance) ion source is also developed to generate multiply charged ions for acceleration to higher energies.
Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Agematsu, Takashi; Mizuhashi, Kiyoshi; Kitano, Toshihiko*; Takayama, Terumitsu*; Orimo, Takao*; Koka, Masashi*; et al.
JAEA-Conf 2008-012, p.44 - 47, 2009/03
no abstracts in English
Agematsu, Takashi; Uno, Sadanori; Chiba, Atsuya; Yamada, Keisuke; Yokoyama, Akihito; Saito, Yuichi; Ishii, Yasuyuki; Sato, Takahiro; Okubo, Takeru; Mizuhashi, Kiyoshi; et al.
JAEA-Review 2008-055, JAEA Takasaki Annual Report 2007, P. 191, 2008/11
Three electrostatic accelerators were operated smoothly in FY 2007, and all the planned experiments were carried out except those canceled by users. The yearly operation time of the tandem accelerator, the single-ended accelerator and the ion implanter amounted to 1949, 2437 and 1900 hours. The high-pressure residual gas of SF is leaking from the SF gas handling system of the tandem accelerator. The most amount of the leak comes out when the accelerator tank pressure is high. Therefore, in order to reduce the leak by lowering the residual gas pressure, a pipe was installed to carry the gas in the high-pressure part of the system for the accelerator to the low-pressure storage tank. As to the ion implanter, Pb ion, which was requested by users, was successfully generated using oven method and accelerated with intensity of 1.5 A.
Yamada, Keisuke; Saito, Yuichi; Mizuhashi, Kiyoshi; Okoshi, Kiyonori; Orimo, Takao*; Omae, Akiomi*; Yamada, Naoto*
JAEA-Conf 2008-005, p.114 - 117, 2008/03
no abstracts in English
Mizuhashi, Kiyoshi; Uno, Sadanori; Okoshi, Kiyonori; Chiba, Atsuya; Yamada, Keisuke; Saito, Yuichi; Ishii, Yasuyuki; Sato, Takahiro; Sakai, Takuro; Yokota, Wataru; et al.
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 197, 2007/02
Three electrostatic accelerators were almost operated smoothly for various experiments in FY 2005. The yearly operation time of each accelerator amounts to 1974, 2359.9, 1859.9 hour for the tandem, the single-ended and the ion implanter, respectively. Main trouble was a short circuit of a part of the ion source in the single-ended accelerator. This lets to the suspension of operation for fifteen days. As features in FY 2005, the generation of the power cut by thunderbolts and large earthquakes were abounding. By this natural force, the Turbo-molecular pump was broken, experiment was interrupted and then the inspection of accelerator facility was carried out every time. New beam acceleration and improvement of each accelerator were carried out.
Hayashi, Takao; Tobita, Kenji; Nishio, Satoshi; Ikeda, Kazuki*; Nakamori, Yuko*; Orimo, Shinichi*; DEMO Plant Design Team
Fusion Engineering and Design, 81(8-14), p.1285 - 1290, 2006/02
Times Cited Count:23 Percentile:81.45(Nuclear Science & Technology)Neutron transport calculations were carried out to evaluate the capability of metal hydrides and borohydrides as an advanced shielding material. Some hydrides indicated considerably higher hydrogen content than polyethylene and solid hydrogen. The hydrogen-rich hydrides show superior neutron shielding capability to the conventional materials. From the temperature dependence of dissociation pressure, ZrH and TiH can be used without releasing hydrogen at the temperature of less than 640 C at 1 atm. ZrH and Mg(BH) can reduce the thickness of the shield by 30% and 20% compared to a combination of steel and water, respectively. Mixing some hydrides with F82H produces considerable effects in -ray shielding. The neutron and -ray shielding capabilities decrease in order of ZrH Mg(BH) and F82H TiH and F82H water and F82H.