Refine your search:     
Report No.
 - 
Search Results: Records 1-20 displayed on this page of 40

Presentation/Publication Type

Initialising ...

Refine

Journal/Book Title

Initialising ...

Meeting title

Initialising ...

First Author

Initialising ...

Keyword

Initialising ...

Language

Initialising ...

Publication Year

Initialising ...

Held year of conference

Initialising ...

Save select records

Journal Articles

MIRS: an imaging spectrometer for the MMX mission

Barucci, M. A.*; Reess, J.-M.*; Bernardi, P.*; Doressoundiram, A.*; Fornasier, S.*; Le Du, M.*; Iwata, Takahiro*; Nakagawa, Hiromu*; Nakamura, Tomoki*; Andr$'e$, Y.*; et al.

Earth, Planets and Space (Internet), 73(1), p.211_1 - 211_28, 2021/12

 Times Cited Count:8 Percentile:81.82(Geosciences, Multidisciplinary)

The MMX InfraRed Spectrometer (MIRS) is an imaging spectrometer on board of MMX JAXA mission. MIRS is built at LESIA-Paris Observatory in collaboration with four other French laboratories, collaboration and financial support of CNES and close collaboration with JAXA and MELCO. The instrument is designed to fully accomplish MMX's scientific and measurement objectives. MIRS will remotely provide near-infrared spectral maps of Phobos and Deimos containing compositional diagnostic spectral features that will be used to analyze the surface composition and to support the sampling site selection. MIRS will also study Mars atmosphere, in particular to spatial and temporal changes such as clouds, dust and water vapor.

Journal Articles

Current status of electrostatic accelerator at TIARA

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

Journal Articles

Current status of electrostatic accelerators at TIARA

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

JAEA Reports

Study to improve recriticality evaluation methodology after severe accident (Joint research)

Kugo, Teruhiko; Ishikawa, Makoto; Nagaya, Yasunobu; Yokoyama, Kenji; Fukaya, Yuji; Maruyama, Hiromi*; Ishii, Yoshihiko*; Fujimura, Koji*; Kondo, Takao*; Minato, Hirokazu*; et al.

JAEA-Research 2013-046, 53 Pages, 2014/03

JAEA-Research-2013-046.pdf:4.42MB

The present report summarizes the results of a 2-year cooperative study between JAEA and Hitachi-GE in order to contribute to the settlement of the Fukushima-Daiichi Nuclear Power Plants which suffered from the severe accident on March 2011. In the present study, the possible scenarios to reach the recriticality events in Fukushima-Daiichi were investigated first. Then, the analytical methodology to evaluate the time-dependent recriticality events has been developed by modelling the reactivity insertion rate and the possible feedback according to the recriticality scenarios identified in the first step. The methodology developed here has been equipped as a transient simulation tool, PORCAS, which is operated on a multi-purpose platform for reactor analysis, MARBLE. Finally, the radiation exposure rates by the postulated recriticality events in Fukushima-Daiichi were approximately evaluated to estimate the impact to the public environment.

Journal Articles

Operation of electrostatic accelerators

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.

Journal Articles

Current status of electrostatic accelerators at TIARA

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.

Journal Articles

Manufacturing and development of JT-60SA vacuum vessel and divertor

Sakasai, Akira; Masaki, Kei; Shibama, Yusuke; Sakurai, Shinji; Hayashi, Takao; Nakamura, Shigetoshi; Ozaki, Hidetsugu; Yokoyama, Kenji; Seki, Yohji; Shibanuma, Kiyoshi; et al.

Proceedings of 24th IAEA Fusion Energy Conference (FEC 2012) (CD-ROM), 8 Pages, 2013/03

The JT-60SA vacuum vessel (VV) and divertor are key components for the performance requirements. Therefore the manufacturing and development of VV and divertor are in progress, inclusive of the superconducting magnets. The vacuum vessel has a double wall structure in high rigidity to withstand electromagnetic force at disruption and to keep high toroidal one-turn resistance. In addition, the double wall structure fulfills originally two functions. (1) The remarkable reduction of the nuclear heating in the superconducting magnets is made by boric-acid water circulated in the double wall. (2) The effective baking is enabled by nitrogen gas flow of 200$$^{circ}$$C in the double wall after draining of water. Three welding types were chosen for the manufacturing of the double wall structure VV to minimize deformation by welding. Divertor cassettes with fully water cooled plasma facing components were designed to realize the JT-60SA lower single null closed divertor. The divertor cassettes in the radio-active VV have been developed to ensure compatibility with remote handling (RH) maintenance in order to allow long pulse high performance discharges with high neutron yield. The manufacturing of divertor cassettes with typical accuracy of *1 mm has been successfully completed. Brazed CFC (carbon fiber composite) monoblock targets for a divertor target have been manufactured by precise control of tolerances inside CFC blocks. The infrared thermography test of monoblock targets has been developed as new acceptance inspection.

Journal Articles

Operation of electrostatic accelerators

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.

Journal Articles

Observation of the partial Fermi surface quenching in the noncentrosymmetric superconductor Mo$$_3$$Al$$_2$$C

Koyama, Takehide*; Ozaki, Yuzuru*; Ueda, Koichi*; Mito, Takeshi*; Kohara, Takao*; Waki, Takeshi*; Tabata, Yoshikazu*; Michioka, Chishiro*; Yoshimura, Kazuyoshi*; Suzuki, Michito; et al.

Journal of the Physical Society of Japan, 81(Suppl.B), p.SB008_1 - SB008_5, 2012/12

 Times Cited Count:1 Percentile:10.83(Physics, Multidisciplinary)

The normal state properties of a noncentrosymmetric superconductor Mo$$_3$$Al$$_2$$C are studied by means of the nuclear magnetic resonance (NMR) experiment. The change of NMR line shape and the peak of the nuclear spin-echo decay rate at $$simeq$$ 130 K indicate that the Mo$$_3$$Al$$_2$$C exhibits the phase transition prior to the emergence of superconductivity. The reduction in the conduction electron density is inferred from the decrease in the nuclear spin-lattice relaxation rate. The nature of the newly found phase transition is discussed by considering the result of the first principle calculations, indicating a good nesting property of the Fermi surfaces.

Journal Articles

Operation of electrostatic accelerators at TIARA

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$$_{6}$$ gas from the base flange on the tank by the Viton gasket of rectangular cross section at the new type.

Journal Articles

Current status of electrostatic accelerators at TIARA

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$$_{6}$$ 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.

Journal Articles

Operation of the electrostatic accelerators

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.

Journal Articles

Partial gap opening on the Fermi surface of the noncentrosymmetric superconductor Mo$$_3$$Al$$_2$$C

Koyama, Takehide*; Ozaki, Yuzuru*; Ueda, Koichi*; Mito, Takeshi*; Kohara, Takao*; Waki, Tsuyoshi*; Tabata, Yoshikazu*; Michioka, Chishiro*; Yoshimura, Kazuyoshi*; Suzuki, Michito; et al.

Physical Review B, 84(21), p.212501_1 - 212501_4, 2011/12

 Times Cited Count:11 Percentile:44.74(Materials Science, Multidisciplinary)

The results of $$^{27}$$Al nuclear magnetic resonance and specific-heat measurements of the noncentrosymmetric superconductor Mo$$_3$$Al$$_2$$C are reported. The phase transition around 130 K is inferred from a distinct change in the NMR spectrum, a clear peak in the spin-echo decay rate, and an anomaly in the specific heat. Possibility of charge-density wave ordering around 130 K is discussed by calculating the Fermi surfaces in the normal states and considering the partial quenching of the Fermi surfaces with the decrease in 1/$$T$$$$_1$$ below the superconducting transition temperature.

Journal Articles

Current status of electrostatic accelerators at TIARA

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.

Journal Articles

Operation of the electrostatic accelerators

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.

Journal Articles

Current status of electrostatic accelerators at TIARA

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.

Journal Articles

Current status of electrostatics accelerators at TIARA

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

Journal Articles

Operation of the electrostatic accelerators

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$$_{6}$$ gas for the single-ended accelerator was purified, and its storage tank was repainted. As to the ion implanter, Bi$$_{2}$$ ion, which was requested by users, was successfully generated and accelerated with intensity of 0.5$$mu$$A.

Journal Articles

Current status of electrostatic accelerators at TIARA

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

Journal Articles

Operation of the electrostatic accelerators

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$$_{6}$$ is leaking from the SF$$_{6}$$ 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 $$mu$$A.

40 (Records 1-20 displayed on this page)