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JAEA Reports

Conceptual study of Post Irradiation Examination (PIE) Facility at J-PARC

Saito, Shigeru; Meigo, Shinichiro; Makimura, Shunsuke*; Hirano, Yukinori*; Tsutsumi, Kazuyoshi*; Maekawa, Fujio

JAEA-Technology 2023-025, 48 Pages, 2024/03

JAEA-Technology-2023-025.pdf:3.11MB

JAEA has been developing Accelerator-Driven Systems (ADS) for research and development of nuclear transmutation using accelerators in order to reduce the volume and hazardousness of high-level radioactive waste generated by nuclear power plants. In order to prepare the material irradiation database necessary for the design of ADS and to study the irradiation effects in Lead-Bismuth Eutectic (LBE) alloys, a proton irradiation facility is under consideration at J-PARC. In this proton irradiation facility, 250 kW proton beams will be injected into the LBE spallation target, and irradiation tests under LBE flow will be performed for candidate structural materials for ADS. Furthermore, semiconductor soft-error tests, medical RI production, and proton beam applications will be performed. Among these, Post Irradiation Examination (PIE) of irradiated samples and RI separation and purification will be carried out in the PIE facility to be constructed near the proton irradiation facility. In this PIE facility, PIE of the equipment and samples irradiated in other facilities in J-PARC will also be performed. This report describes the conceptual study of the PIE facility, including the items to be tested, the test flow, the facilities, the test equipment, etc., and the proposed layout of the facility.

Journal Articles

Novel ${it Methanobacterium}$ strain induces severe corrosion by retrieving electrons from Fe$$^{0}$$ under a freshwater environment

Hirano, Shinichi*; Ihara, Sota*; Wakai, Satoshi*; Dotsuta, Yuma; Otani, Kyohei; Kitagaki, Toru; Ueno, Fumiyoshi; Okamoto, Akihiro*

Microorganisms (Internet), 10(2), p.270_1 - 270_12, 2022/02

 Times Cited Count:7 Percentile:84.82(Microbiology)

To understand the role of methanogens in corrosion under anoxic conditions in freshwater, we investigated the corrosion activities of methanogens in samples collected from groundwater and rivers. We enriched microorganisms that can grow with CO$$_{2}$$/NaHCO$$_{3}$$ and Fe$$^{0}$$ as the sole carbon source and electron donor, respectively, in ground fresh water. Electrochemical analysis revealed that ${it Methanobacterium}$ strain can uptake electrons from the cathode at lower than -0.61 V vs SHE and has a redox-active component with electrochemical potential different from those of other previously reported methanogens with extracellular electron transfer ability. This study indicated the corrosion risk by methanogens capable of taking up electrons from Fe$$^{0}$$ in anoxic freshwater environments and the necessity of understanding the corrosion mechanism to contribute to risk diagnosis.

Journal Articles

A Task of microbiologically influenced corrosion in Fukushima Daiichi Decommissioning

Wakai, Satoshi*; Hirano, Shinichi*; Ueno, Fumiyoshi; Okamoto, Akihiro*

Zairyo To Kankyo, 70(12), p.491 - 496, 2021/12

After Fukushima Daiichi Nuclear Power Station accident, various corrosion mitigating activities have been treated, and severe corrosion incident have never taken placed. On the other hand, the facilities were exposed sea water, and some of them have continuously exposed to ground water. The exposure of metal materials to environmental water has a risk of microbiologically influenced corrosion (MIC). In this paper, we summarize the latest knowledge of MIC and the task of MIC in the decommissioning of Fukushima Daiichi Nuclear Power Station.

Journal Articles

Long beam pulse extraction by the laser charge exchange method using the 3-MeV linac in J-PARC

Takei, Hayanori; Hirano, Koichiro; Meigo, Shinichiro; Tsutsumi, Kazuyoshi*

Proceedings of 8th International Beam Instrumentation Conference (IBIC 2019) (Internet), p.595 - 599, 2020/06

Japan Proton Accelerator Research Complex (J-PARC) has a plan to build the Transmutation Physics Experimental Facility (TEF-P), in which a 400-MeV proton beam will be delivered from negative hydrogen (H$$^{-}$$) accelerated by the linac. Since the TEF-P requires a stable proton beam with a power of less than 10 W, a steady and meticulous beam extraction method is required to extract a small amount of the proton beam from the high power beam using 250 kW. To fulfill this requirement, we have developed beam extraction based on the Laser Charge Exchange (LCE) method. For the demonstration present beam extraction technique, an experiment was conducted using H$$^{-}$$ beam accelerated by the 3-MeV linac at RFQ test-stand in J-PARC. As a result of the experiment with continuous wave (CW) of the Laser, a charge-exchanged long-pulsed H$$^{+}$$ beam with a power of about 0.70 W equivalent was successfully obtained under the TEF-P beam condition.

Journal Articles

Upgrade of the 3-MeV linac for testing of accelerator components at J-PARC

Kondo, Yasuhiro; Hirano, Koichiro; Ito, Takashi; Kikuzawa, Nobuhiro; Kitamura, Ryo; Morishita, Takatoshi; Oguri, Hidetomo; Okoshi, Kiyonori; Shinozaki, Shinichi; Shinto, Katsuhiro; et al.

Journal of Physics; Conference Series, 1350, p.012077_1 - 012077_7, 2019/12

 Times Cited Count:1 Percentile:52.28(Physics, Particles & Fields)

We have upgraded a 3-MeV linac at J-PARC. The ion source is same as the J-PARC linac's, and the old 30-mA RFQ is replaced by a spare 50-mA RFQ, therefore, the beam energy is 3 MeV and the nominal beam current is 50 mA. The main purpose of this system is to test the spare RFQ, but also used for testing of various components required in order to keep the stable operation of the J-PARC accelerator. The accelerator has been already commissioned, and measurement programs have been started. In this paper, present status of this 3-MeV linac is presented.

Journal Articles

Genetic survey of indigenous microbial eukaryotic communities, mainly fungi, in sedimentary rock matrices of deep terrestrial subsurface

Saito, Yoshimoto*; Hirano, Shinichi*; Nagaoka, Toru*; Amano, Yuki

Ecological Genetics and Genomics, 12, p.100042_1 - 100042_9, 2019/10

Culture-independent molecular techniques enable us to analyze microflora in various environments. Many uncultured prokaryotes have been detected by the molecular methods from extreme environments, including anaerobic, no light, high-pressure, and high temperature. Recently, microbial eukaryotes were also detected in deep-sea environments, suggesting that microbial eukaryotes can adapt to a wider range of environments than previously thought. Here, we performed a culture-independent analysis of eukaryotes from approximately -250 m depth in the Horonobe Underground Research Laboratory at Horonobe, Japan. Our results indicate that fungi are the dominant eukaryotic flora in deep sedimentary rocks of Horonobe. We detected a wide range of species, including Zygomycete, Basidiomycete, and Ascomycete fungi from the rocks. This study is the first report of eukaryotic diversity in deep subsurface sedimentary rocks.

Journal Articles

Beam extraction by the laser charge exchange method using the 3-MeV LINAC in J-PARC

Takei, Hayanori; Hirano, Koichiro; Tsutsumi, Kazuyoshi; Meigo, Shinichiro

Plasma and Fusion Research (Internet), 13(Sp.1), p.2406012_1 - 2406012_6, 2018/03

The Japan Proton Accelerator Research Complex (J-PARC) has a plan to build the Transmutation Physics Experimental Facility (TEF-P), in which a 400-MeV negative proton (H$$^{-}$$) beam will be delivered from the J-PARC linac. Since the TEF-P requires a stable proton beam with a power of less than 10 W, a stable and meticulous beam extraction method is required to extract a small amount of the proton beam from the high power beam using 250 kW. To fulfil this requirement, the Laser Charge Exchange (LCE) method has been developed. To demonstrate the charge exchange of the H$$^{-}$$, a preliminary LCE experiment was conducted using a linac with energy of 3 MeV in J-PARC. As a result of the experiment, a charge-exchanged H$$^{+}$$ beam with a power of about 8 W equivalent and an accuracy of about 2% was obtained under the J-PARC linac beam condition.

Journal Articles

Beam extraction by the laser charge exchange method using the 3-MeV linac in J-PARC

Takei, Hayanori; Hirano, Koichiro; Meigo, Shinichiro; Tsutsumi, Kazuyoshi*

Proceedings of 6th International Beam Instrumentation Conference (IBIC 2017) (Internet), p.435 - 439, 2018/03

The Japan Proton Accelerator Research Complex (J-PARC) has a plan to build the Transmutation Physics Experimental Facility (TEF-P), in which a 400-MeV negative proton (H$$^{-}$$) beam will be delivered from the J-PARC linac. Since the TEF-P requires a stable proton beam with a power of less than 10 W, a stable and meticulous beam extraction method is required to extract a small amount of the proton beam from the high power beam using 250 kW. To fulfil this requirement, the Laser Charge Exchange (LCE) method has been developed. To demonstrate the charge exchange of the H$$^{-}$$, a preliminary LCE experiment was conducted using a linac with energy of 3 MeV in J-PARC. As a result of the experiment, a charge-exchanged H$$^{+}$$ beam with a power of about 8 W equivalent and an accuracy of about 2% was obtained under the J-PARC linac beam condition.

Journal Articles

A 3 MeV linac for development of accelerator components at J-PARC

Kondo, Yasuhiro; Asano, Hiroyuki*; Chishiro, Etsuji; Hirano, Koichiro; Ishiyama, Tatsuya; Ito, Takashi; Kawane, Yusuke; Kikuzawa, Nobuhiro; Meigo, Shinichiro; Miura, Akihiko; et al.

Proceedings of 28th International Linear Accelerator Conference (LINAC 2016) (Internet), p.298 - 300, 2017/05

We have constructed a linac for development of various accelerator components at J-PARC. The ion source is same as the J-PARC linac's, and the RFQ is a used one in the J-PARC linac. The beam energy is 3 MeV and nominal beam current is 30 mA. The accelerator has been already commissioned, and the first development program, laser-charge-exchange experiment for the transmutation experimental facility, has been started. In this paper, present status of this 3-MeV linac is presented.

Journal Articles

Present status of the laser charge exchange test using the 3-MeV linac in J-PARC

Takei, Hayanori; Chishiro, Etsuji; Hirano, Koichiro; Kondo, Yasuhiro; Meigo, Shinichiro; Miura, Akihiko; Morishita, Takatoshi; Oguri, Hidetomo; Tsutsumi, Kazuyoshi

Proceedings of 5th International Beam Instrumentation Conference (IBIC 2016) (Internet), p.736 - 739, 2017/03

The Accelerator-driven System (ADS) is one of the candidates for transmuting long-lived nuclides, such as minor actinide (MA), produced by nuclear reactors. For efficient transmutation of the MA, a precise pre-diction of neutronics of ADS is required. In order to obtain the neutronics data for the ADS, the Japan Pro-ton Accelerator Research Complex (J-PARC) has a plan to build the Transmutation Physics Experimental Facility (TEF-P), in which a 400-MeV negative proton (H$$^{-}$$) beam will be delivered from the J-PARC linac. Since the TEF-P requires a stable proton beam with a power of less than 10W, a stable and meticulous beam extraction method is required to extract a small amount of the proton beam from the high power beam using 250kW. To fulfil this requirement, the Laser Charge Exchange (LCE) method has been developed. The LCE strips the electron of the H$$^{-}$$ beam and neutral protons will separate at the bending magnet in the proton beam transport. To demonstrate the charge exchange of the H$$^{-}$$, a preliminary LCE experiment was conducted using a linac with energy of 3MeV in J-PARC. As a result of the experiment, a charge-exchanged H$$^{+}$$ beam with a power of about 5W equivalent was obtained under the J-PARC linac beam condition, and this value almost satisfied the power requirement of the proton beam for the TEF-P.

Journal Articles

Development of a control system at a 3 MeV linac in J-PARC

Sawabe, Yuki*; Ishiyama, Tatsuya; Takahashi, Daisuke; Kato, Yuko; Suzuki, Takahiro*; Hirano, Koichiro; Takei, Hayanori; Meigo, Shinichiro; Kikuzawa, Nobuhiro; Hayashi, Naoki

Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.647 - 651, 2016/11

In the J-PARC, a 3 MeV linac has been developed for the tests of beam scraper irradiation and charge exchange by high-power laser. To accomplish tests efficiently and safely, the control system for 3 MeV was designed and developed, and this system consists of four subsystems, personal protection system, machine protection system, timing system, and remote control system using the EPICS. In this paper, the details of control system for a 3 MeV linac are presented.

Journal Articles

Development of beam scrapers using a 3-Mev linac at J-PARC

Hirano, Koichiro; Asano, Hiroyuki; Ishiyama, Tatsuya; Ito, Takashi; Okoshi, Kiyonori; Oguri, Hidetomo; Kondo, Yasuhiro; Kawane, Yusuke; Kikuzawa, Nobuhiro; Sato, Yoshikatsu; et al.

Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.310 - 313, 2016/11

We have used a beam scraper with the incident angle of 65deg to reduce the beam power deposition density in the MEBT between a 324 MHz RFQ and a 50-MeV DTL of the J-PARC linac. The 65$$^{circ}$$ scraper was irradiated by the H$$^{-}$$ beam up to particle number of 1.47E22. We observed a lot of surface projections with several hundred micrometers high in the beam irradiation damage on the scraper by using the laser microscope. In order to study the limits of scrapers, we constructed a new 3 MeV linac at J-PARC. We will conduct the scraper irradiation test at the end of this year.

Journal Articles

Preliminary results of the laser charge exchange test using the 3-MeV linac in J-PARC

Takei, Hayanori; Hirano, Koichiro; Tsutsumi, Kazuyoshi; Chishiro, Etsuji; Miura, Akihiko; Kondo, Yasuhiro; Morishita, Takatoshi; Oguri, Hidetomo; Meigo, Shinichiro

Proceedings of 13th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.987 - 991, 2016/11

Accelerator-driven system (ADS) is one of candidates to transmute long-lived nuclides such as minor actinide (MA) produced at nuclear reactor. For efficient transmutation of the MA, precise prediction of neutronics of ADS is indispensable. In order to obtain the neutronics data for the ADS, J-PARC has a plan to build the Transmutation Physics Experimental Facility (TEF-P). Since the TEF-P requires stable power of the beam and will operate with thermal power less than 500 W and the proton beam power of 10 W so that a stable and meticulous beam extraction method is required to extract small amount of the beam from the high power LINAC beam with 250 kW. To fulfill requirement, Laser charge exchange method (LCE) has been developed for delivery of 400-MeV proton beam with 25Hz to the TEF-P. The LCE strips the electron of H$$^{-}$$ beam and H$$^{0}$$ will separate at the bending magnet at the proton beam transport. The LCE device consists of YAG-laser with high power as 1.6 J/shot and 25 Hz and transport control system with high accuracy of the beam position. For the demonstration of the charge exchange of the H$$^{-}$$, the further LCE tests is conducted using H$$^{-}$$ beam with energy of 3-MeV at RFQ test stand in J-PARC. In this paper, present status of LCE tests is presented.

Journal Articles

Carbon steel corrosion induced by microbial community in soil environment and its analysis

Hirano, Shinichi*; Nagaoka, Toru*; Ise, Kotaro; Amano, Yuki; Matsumoto, Norio*

Zairyo To Kankyo, 64(12), p.535 - 539, 2015/12

To obtain the knowledge about the corrosion ability and its mechanism as a target the soil environment microorganisms, lake mud was cultured with metallic iron. As a result, corrosion of carbon steel was observed with sulfate reduction and methane producing activity in brackish medium with lactate as substrate. Inhibition test of SRB and MPA suggested that SRB plays a major role for this corrosion, and MPA enhanced corrosion activity by the coexistence of SRB.

Journal Articles

Status of decommissioning of the Plutonium Fuel Fabrication Facility and R&Ds of dismantling technologies for gloveboxes

Kimura, Yasuhisa; Hirano, Hiroshi; Watahiki, Masatoshi; Kuba, Meiji; Ishikawa, Shinichiro

Dekomisshoningu Giho, (52), p.45 - 54, 2015/09

The Plutonium Fuel Fabrication Facility (PFFF) of the Japan Atomic Energy Agency is now in its decommissioning phase. In the PFFF, terminated gloveboxes have been dismantled. Gloveboxes to be dismantled are surrounded by a plastic enclosure to prevent contamination from being spread into process room. Dismantling operations for gloveboxes are performed manually by workers, each wearing an air-feed suit. However, the mental and physical loads placed on workers wearing the air-feed suits are intensively high. Therefore, R&Ds on new dismantling technologies including utilization of heavy machines covered with plastic enclosure for anti-contamination have been started to reduce the potential risks associated with workers and decommissioning costs. In this paper, the status of decommissioning of the PFFF and the overview of developed dismantling technologies for $$alpha$$-tight gloveboxes are described.

Journal Articles

Development of phase rotation system for RF-chopper at J-PARC Linac

Futatsukawa, Kenta*; Kobayashi, Tetsuya*; Sato, Fumiaki; Shinozaki, Shinichi; Chishiro, Etsuji; Hirano, Koichiro; Fang, Z.*; Fukui, Yuji*; Hori, Toshihiko; Michizono, Shinichiro*

Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1317 - 1320, 2015/09

In the J-PARC linac, an RF deflector installed in 3-MeV Medium Energy Beam Transport (MEBT1) is used to kick the unnecessary beam and the intermediate-pulse like a comb is created. The kicked beam leads to a scraper downstream the RF deflector and lose all kinetic energy. When the beam current increases to 50 mA of the design value, the heat load of a scraper to irradiate the kicked beam increases and its surface is predicted to be damaged. Therefore, we are preparing the tandem scrapers to reduce the damage. The half of the kicked beam leads to a scraper and the residual is to the other. The chopping operation is achieved by rotating the phase of the RF deflector in the periodic cycles by the LLRF system. We will introduce the phase rotation system and the test results.

Journal Articles

Development of RF chopper system at J-PARC Linac, 2

Hirano, Koichiro; Kondo, Yasuhiro; Kawane, Yusuke; Shinozaki, Shinichi; Miura, Akihiko; Morishita, Takatoshi; Sawabe, Yuki; Sugimura, Takashi*; Naito, Fujio*; Fang, Z.*; et al.

Proceedings of 12th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.944 - 947, 2015/09

Two RF-deflecting cavities as a chopper and a beam scraper have been used in the MEBT1 between a 324 MHz RFQ and a 50-MeV DTL of the J-PARC Linac. We replaced with a newly fabricated RF chopper to decrease beam loss for the operation with 50 mA. We installed two new scrapers to absorb the higher power of the deflected beam by the RF chopper. This paper describes the RF chopper system and beam irradiation test results of the scraper.

Journal Articles

Beam test of a new radio frequency quadrupole linac for the Japan Proton Accelerator Research Complex

Kondo, Yasuhiro; Morishita, Takatoshi; Yamazaki, Saishun; Hori, Toshihiko; Sawabe, Yuki; Chishiro, Etsuji; Fukuda, Shimpei; Hasegawa, Kazuo; Hirano, Koichiro; Kikuzawa, Nobuhiro; et al.

Physical Review Special Topics; Accelerators and Beams, 17(12), p.120101_1 - 120101_8, 2014/12

 Times Cited Count:6 Percentile:42.9(Physics, Nuclear)

We performed a beam test of a new radio frequency quadrupole linac (RFQ III) for the beam current upgrade of the Japan Proton Accelerator Research Complex. First, the conditioning of RFQ III was conducted, and after 20 h of conditioning, RFQ III became very stable with a nominal peak power and duty factor of 400 kW and 1.5%, respectively. An off-line beam test was subsequently conducted before installation in the accelerator tunnel. The transmission, transverse emittance, and energy spread of the 50-mA negative hydrogen beam from RFQ III were measured and compared with simulation results. The experiment and simulation results showed good agreement; therefore, we conclude that the performance of RFQ III conforms to its design.

Journal Articles

Present status of J-PARC linac

Oguri, Hidetomo; Hasegawa, Kazuo; Ito, Takashi; Chishiro, Etsuji; Hirano, Koichiro; Morishita, Takatoshi; Shinozaki, Shinichi; Ao, Hiroyuki; Okoshi, Kiyonori; Kondo, Yasuhiro; et al.

Proceedings of 11th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.389 - 393, 2014/10

no abstracts in English

Journal Articles

Development of RF chopper system at J-PARC Linac

Hirano, Koichiro; Ito, Takashi; Kondo, Yasuhiro; Shinozaki, Shinichi; Chishiro, Etsuji; Miura, Akihiko; Morishita, Takatoshi; Ikegami, Masanori*; Kubota, Chikashi*; Sugimura, Takashi*; et al.

Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.858 - 861, 2014/06

Two RF-deflecting cavities as a chopper and a beam scraper have been used in the MEBT between a 324 MHz RFQ and a 50-MeV DTL of the J-PARC Linac. We plan to increase a peak beam current up to 50 mA by replacing an ion source and a RFQ after the summer shutdown in 2014. Beam loss occurs in the RF chopper for the 50 mA operation. Moreover, the beam scraper cannot fully stand the beam load with 50 mA, 0.5 ms, 3 MeV, and 25 Hz. We have studied the new RF chopper cavity by using HFSS code and the tandem scraper system with two scrapers.

64 (Records 1-20 displayed on this page)