Final report on feasibility study of Pu monitoring and solution measurement of high active liquid waste containing fission product at Reprocessing Facility

Sekine, Megumi; Matsuki, Takuya; Suzuki, Satoshi*; Tsutagi, Koichi; Nishida, Naoki; Kitao, Takahiko; Tomikawa, Hirofumi; Nakamura, Hironobu; LaFleur, A.*; Browne, M.*

JAEA-Technology 2019-023, 160 Pages, 2020/03

JAEA-Technology-2019-023.pdf:9.43MB

The International Atomic Energy Agency (IAEA) has proposed in its Research and Development plan (STR-385), the development of technology to enable real-time flow measurement of nuclear material as a part of an advanced approach to effective and efficient safeguards for reprocessing facilities. To address this, Japan Atomic Energy Agency (JAEA) has been tackling development of a new detector to enable monitoring of Pu in solutions with numerous FPs as a joint research program with U.S. DOE to cover whole reprocessing process. In this study, High Active Liquid Waste (HALW) Storage Facility in Tokai Reprocessing Plant was used as the test field. At first, the design information of HALW storage tank and radiation (type and intensity) were investigated to develop a Monte Carlo N-Particle Transport Code (MCNP) model. And then, dose rate distribution outside/ inside of the concrete cell where the HALW tank is located was measured to design new detectors and check MCNP model applicability. Using the newly designed detectors, gamma rays and neutron were continuously measured at the outside/ inside of the concrete cell to assess the radiation characteristics and to optimize detector position. Finally, the applicability for Pu monitoring technology was evaluated based on the simulation results and gamma-ray/neutron measurement results. We have found that there is possibility to monitor the change of Pu amount in solution by combination both of gamma-ray and neutron measurement. The results of this study suggested the applicability and capability of the Pu motoring to enhance safeguards for entire reprocessing facility which handles Pu with FP as a feasibility study. This is final report of this project.

Status of J-PARC accelerators

Hasegawa, Kazuo; Kinsho, Michikazu; Oguri, Hidetomo; Yamamoto, Kazami; Hayashi, Naoki; Yamazaki, Yoshio; Naito, Fujio*; Yoshii, Masahito*; Yamamoto, Noboru*; Koseki, Tadashi*

Proceedings of 15th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1317 - 1321, 2018/08

After the summer shutdown in 2017, the J-PARC restarted user operation in late October. The Materials and Life Science Experimental Facility (MLF) used a spare target and the beam power was limited to 150-200kW. The target was replaced with a new one in the summer shutdown. The beam power was for user operation gradually increased from 300 kW to 500 kW. We have successfully demonstrated 1MW 1hour operation in July 2018. The beam power for the neutrino experimental facility (NU) was 440 kW to 470 kW. The beam was delivered to the hadron experimental facility (HD) from January to February in 2018. The repetition rate of the main ring was shortened from 5.52 to 5.20 seconds, the beam power was increased from 44 to 50 kW. From March 2018, we delivered to the NU at 490 kW stably. In the fiscal year of 2017, the availabilities for the MLF, NU and HD are 93%, 89% and 66%, respectively.

Status of J-PARC accelerators

Hasegawa, Kazuo; Kinsho, Michikazu; Oguri, Hidetomo; Yamamoto, Kazami; Hayashi, Naoki; Yamazaki, Yoshio; Naito, Fujio*; Hori, Yoichiro*; Yamamoto, Noboru*; Koseki, Tadashi*

Proceedings of 14th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1317 - 1321, 2017/12

After the summer shutdown in 2016, the J-PARC restarted user operation late in October for the neutrino experiments (NU) and early in November for the materials and life science experimental facility (MLF). The beam power for the NU was 420 kW in May 2016, but increased to 470 kW in February 2017 thanks to the change and optimization of operation parameters. For the hadron experimental facility (HD), we started beam tuning in April, but suspended by a failure of the electro static septum. After the treatment, we delivered beam at the power of 37 kW. We delivered beam at 150kW for the MLF. In the fiscal year of 2016, the linac, the 3 GeV synchrotron (RCS) and the MLF were stable and the availability was high at 93%. On the contrary, the main ring has several failures and the availabilities were 77% and 84% for NU and HD, respectively.

Feasibility study of technology for Pu solution monitoring including FP; Composition research of high active liquid waste and radiation measurement results on the surface of cell

Matsuki, Takuya; Masui, Kenji; Sekine, Megumi; Tanigawa, Masafumi; Yasuda, Takeshi; Tsutagi, Koichi; Ishiyama, Koichi; Nishida, Naoki; Horigome, Kazushi; Mukai, Yasunobu; et al.

Proceedings of INMM 57th Annual Meeting (Internet), 9 Pages, 2016/07

The International Atomic Energy Agency (IAEA) has proposed in its long-term research and development (R&D) plan, development of a real-time measurement technology to monitor and verify nuclear material movement continuously as part of an advanced approach to effectively and efficiently conduct safeguards for reprocessing facilities. Since the Tokai Reprocessing Plant (TRP) has solutions containing both Pu and fission products (FP), a new detector development project to monitor Pu with FP is being carried out from 2015 to 2017. This project is mainly conducted in the High Active Liquid Waste Storage (HALWS) in the TRP. For the first step of this project, as the confirmation of composition of high active liquid waste (HALW) to evaluate neutron/-ray emitted from solution in the selected HALW tank which has the most amount of Pu in HALW tanks at the TRP, we took HALW sample and conducted -ray spectrum measurement for HALW. As a study of detector setting location, to survey the available neutron/-ray (i.e. intensity) at the outside surface of the cell where HALW tank is located, we implemented continuous measurement by neutron/-ray detector. In this paper, we report three -ray peaks related with Pu and Pu measured in the composition research of HALW, which is needed to identify Pu amount by the new detector that we are developing and the result of radiation measurement on the surface of the cell.

Beam power and residual dose history of J-PARC RCS

Yamamoto, Kazami; Hotchi, Hideaki; Harada, Hiroyuki; Hayashi, Naoki; Kinsho, Michikazu; Saha, P. K.; Tamura, Fumihiko; Yamamoto, Masanobu; Yoshimoto, Masahiro; Nakane, Yoshihiro; et al.

Progress in Nuclear Science and Technology (Internet), 4, p.238 - 242, 2014/04

https://doi.org/10.15669/pnst.4.238

A 3 GeV rapid cycling synchrotron (RCS) at J-PARC was commissioned in October 2007. Afterwards, the beam intensity was increased through a beam study, and the RCS has continuously provided a proton beam 100 kW to the neutron target since October 2009. With renewed efforts brought about by beam commissioning, we have reduced losses in the RCS and achieved low-loss operation. We present the history of the operational beam power and the residual dose distributions after operation.

Beam commissioning and operation of the Japan Proton Accelerator Research Complex 3-GeV rapid cycling synchrotron

Hotchi, Hideaki; Harada, Hiroyuki; Hayashi, Naoki; Kinsho, Michikazu; Saha, P. K.; Shobuda, Yoshihiro; Tamura, Fumihiko; Yamamoto, Kazami; Yamamoto, Masanobu; Yoshimoto, Masahiro; et al.

Progress of Theoretical and Experimental Physics (Internet), 2012(1), p.02B003_1 - 02B003_26, 2012/00

https://doi.org/10.1093/ptep/pts021

The J-PARC 3-GeV RCS is a high-power pulsed proton driver aiming at 1 MW output beam power. The RCS was beam commissioned in October 2007 and made available for user operation in December 2008 with an output beam power of 4 kW. Since then, the output beam power of the RCS has been steadily increasing as per progressions of beam tuning and hardware improvements. So far, the RCS has successfully achieved high-intensity beam trials of up to 420 kW at a low-level intensity loss of less than 1%, and the output beam power for the routine user program has been increased to 210 kW. The most important issues in increasing the output beam power are the control and minimization of beam loss to maintain machine activation within the permissible level. This paper presents the recent progress in the RCS beam power ramp-up scenario, with particular emphasis on our efforts for beam loss issues.

Micrometer-sized magnetic patterning of FeRh films using an energetic ion microbeam

Fujita, Naoki*; Matsui, Toshiyuki*; Kosugi, Shinya*; Sato, Takahiro; Saito, Yuichi; Takano, Katsuyoshi; Koka, Masashi; Kamiya, Tomihiro; Seki, Shu*; Iwase, Akihiro*

Japanese Journal of Applied Physics, 49(6), p.060211_1 - 060211_3, 2010/06

https://doi.org/10.1143/JJAP.49.060211

Extended steady-state and high-beta regimes of net-current free heliotron plasmas in the large helical device

Motojima, Osamu*; Yamada, Hiroshi*; Komori, Akio*; Oyabu, Nobuyoshi*; Kaneko, Osamu*; Kawahata, Kazuo*; Mito, Toshiyuki*; Muto, Takashi*; Ida, Katsumi*; Imagawa, Shinsaku*; et al.

Proceedings of 21st IAEA Fusion Energy Conference (FEC 2006) (CD-ROM), 12 Pages, 2007/03

http://www-naweb.iaea.org/napc/physics/FEC/FEC2006/html/node31.htm#5947

The performance of net-current free Heliotron plasmas has been developed by findings of innovative operational scenarios in conjunction with an upgrade of the heating power and the pumping/fueling capability in the Large Helical Device (LHD). Consequently, the operational regime has been extended, in particular, with regard to high density, long pulse length and high beta. Diversified studies in LHD have elucidated the advantages of net-current free heliotron plasmas. In particular, an Internal Diffusion Barrier (IDB) by combination of efficient pumping of the local island divertor function and core fueling by pellet injection has realized a super dense core as high as 510m, which stimulates an attractive super dense core reactor. Achievements of a volume averaged beta of 4.5 % and a discharge duration of 54-min. with a total input energy of 1.6 GJ (490 kW in average) are also highlighted. The progress of LHD experiments in these two years is overviewed with highlighting IDB, high and long pulse.

Ion-induced electron emission from Si crystal targets covered with noncrystalline Si layers

Kudo, Hiroshi*; Nakamura, Naoki*; Shibuya, Koki*; Narumi, Kazumasa; Yamamoto, Shunya; Naramoto, Hiroshi; Sumitomo, Koji*; Seki, Seiji*

Nuclear Instruments and Methods in Physics Research B, 168(2), p.181 - 191, 2000/06

https://doi.org/10.1016/S0168-583X(99)00852-6

no abstracts in English

Radioactive waste management and disposal scenario for fusion power reactors

Tabara, Takashi*; Yamano, Naoki*; Seki, Yasushi; Aoki, Isao

JAERI-Tech 97-054, 164 Pages, 1997/10

JAERI-Tech-97-054.pdf:5.46MB

no abstracts in English