Improvement of aerosol time-of-flight mass spectrometer for on-line measurement of tiny particles containing alpha emitters (Contract research); FY2022 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Osaka University*

JAEA-Review 2023-040, 104 Pages, 2024/05

JAEA-Review-2023-040.pdf:5.01MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2022. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station (1F), Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2021, this report summarizes the research results of the "Improvement of aerosol time-of-flight mass spectrometer for on-line measurement of tiny particles containing alpha emitters" conducted in FY2022. The present study aims to improve Aerosol Time-Of-Flight Mass Spectrometer (ATOFMS) in order to monitor tiny particles containing alpha emitters such as U and Pu generated in removing debris from the reactors of 1F. In FY2022, we newly fabricated a prototype of the improved ATOFMS and measured collection and detection efficiencies of the particle detection unit and carried out mass measurement using the TOF part.

Measurement of double-differential neutron yields for iron, lead, and bismuth induced by 107-MeV protons for research and development of accelerator-driven systems

Iwamoto, Hiroki; Nakano, Keita; Meigo, Shinichiro; Satoh, Daiki; Iwamoto, Yosuke; Sugihara, Kenta*; Nishio, Katsuhisa; Ishi, Yoshihiro*; Uesugi, Tomonori*; Kuriyama, Yasutoshi*; et al.

EPJ Web of Conferences, 284, p.01023_1 - 01023_4, 2023/05

https://doi.org/10.1051/epjconf/202328401023

For accurate prediction of neutronic characteristics for accelerator-driven systems (ADS) and a source term of spallation neutrons for reactor physics experiments for the ADS at Kyoto University Critical Assembly (KUCA), we have launched an experimental program to measure nuclear data on ADS using the Fixed Field Alternating Gradient (FFAG) accelerator at Kyoto University. As part of this program, the proton-induced double-differential thick-target neutron-yields (TTNYs) and cross-sections (DDXs) for iron, lead, and bismuth have been measured with the time-of-flight (TOF) method. For each measurement, the target was installed in a vacuum chamber on the beamline and bombarded with 107-MeV proton beams accelerated from the FFAG accelerator. Neutrons produced from the targets were detected with stacked, small-sized neutron detectors for several angles from the incident beam direction. The TOF spectra were obtained from the detected signals and the FFAG kicker magnet's logic signals, where gamma-ray events were eliminated by pulse shape discrimination. Finally, the TTNYs and DDXs were obtained from the TOF spectra by relativistic kinematics. The measured TTNYs and DDXs were compared with calculations by the Monte Carlo transport code PHITS with its default physics model of INCL version 4.6 combined with GEM and those with the JENDL-4.0/HE nuclear data library.

High accuracy, high resolution U(n,f) cross section from n_TOF (CERN) from 18 meV to 10 keV

Mastromarco, M.*; Amaducci, S.*; Colonna, N.*; Kimura, Atsushi; 118 of others*

European Physical Journal A, 58(8), p.147_1 - 147_13, 2022/08

https://doi.org/10.1140/epja/s10050-022-00779-7

Basic study for on-line monitoring of tiny particles including alpha emitters by aerosol time-of-flight mass spectroscopy (Contract research); FY2020 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Osaka University*

JAEA-Review 2021-074, 104 Pages, 2022/03

JAEA-Review-2021-074.pdf:4.91MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2020. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2019, this report summarizes the research results of the "Basic study for on-line monitoring of tiny particles including alpha emitters by aerosol time-of-flight mass spectroscopy" conducted in FY2019 and FY2020. Since the final year of this proposal was FY2020, the results for two fiscal years were summarized. The present study aims to conduct a feasibility study of Aerosol time-of-flight mass spectroscopy (ATOFMS) to on-line measurement of tiny particles containing alpha emitters which might be dispersed in cutting the debris in reactors of the Fukushima Daiichi Nuclear Power Station for realizing their real-time monitoring.

Demonstration of a neutron resonance transmission analysis system using a laser-driven neutron source

Hironaka, Kota; Ito, Fumiaki*; Lee, J.; Koizumi, Mitsuo; Takahashi, Tone; Suzuki, Satoshi*; Yogo, Akifumi*; Arikawa, Yasunobu*; Abe, Yuki*

Dai-42-Kai Nihon Kaku Busshitsu Kanri Gakkai Nenji Taikai Kaigi Rombunshu (Internet), 4 Pages, 2021/11

Neutron resonance transmission analysis (NRTA) is a method for non-destructive measurement of nuclear material by using a time-of-flight (TOF) technique with a pulsed neutron source. For NRTA system to carry out the short-distance TOF measurements with high resolutions, a short-pulsed neutron source is required. Laser-driven neutron sources (LDNSs) is very suitable as such a neutron source because of its short pulse width. Moreover, the compactness of the laser system is also expected due to the remarkable development of laser technology in recent years. In the present study, we have developed a technology for applying LDNS to the NRTA system and conducted the demonstration experiment using the LFEX laser at Osaka University to investigate the feasibility of the system. In this experiment, we successfully observed the neutron resonance peaks of indium and silver samples.

Basic study for on-line monitoring of tiny particles including alpha emitters by aerosol time-of-flight mass spectroscopy (Contract research); FY2019 Nuclear Energy Science & Technology and Human Resource Development Project

Collaborative Laboratories for Advanced Decommissioning Science; Osaka University*

JAEA-Review 2020-050, 69 Pages, 2021/01

JAEA-Review-2020-050.pdf:3.79MB

The Collaborative Laboratories for Advanced Decommissioning Science (CLADS), Japan Atomic Energy Agency (JAEA), had been conducting the Nuclear Energy Science & Technology and Human Resource Development Project (hereafter referred to "the Project") in FY2019. The Project aims to contribute to solving problems in the nuclear energy field represented by the decommissioning of the Fukushima Daiichi Nuclear Power Station, Tokyo Electric Power Company Holdings, Inc. (TEPCO). For this purpose, intelligence was collected from all over the world, and basic research and human resource development were promoted by closely integrating/collaborating knowledge and experiences in various fields beyond the barrier of conventional organizations and research fields. The sponsor of the Project was moved from the Ministry of Education, Culture, Sports, Science and Technology to JAEA since the newly adopted proposals in FY2018. On this occasion, JAEA constructed a new research system where JAEA-academia collaboration is reinforced and medium-to-long term research/development and human resource development contributing to the decommissioning are stably and consecutively implemented. Among the adopted proposals in FY2019, this report summarizes the research results of the "Basic study for On-Line Monitoring of Tiny Particles including Alpha Emitters by Aerosol Time-Of-Flight Mass Spectroscopy" conducted in FY2019. The present study aims to conduct a feasibility study of Aerosol Time-Of-Flight Mass Spectroscopy (ATOFMS) technique to on-line measurement of tiny particles including alpha emitters which might be dispersed in cutting debris in reactors of the Fukushima Daiichi Nuclear Power Station for realizing real-time monitoring of the tiny particles. In FY2019, we prepared the solid (U, Zr)O samples and the acidic and basic U solutions as model materials.

Status and perspectives of the neutron time-of-flight facility n_TOF at CERN

Chiaveri, E.*; Aberle, O.*; Alcayne, V.*; Kimura, Atsushi; 124 of others*

EPJ Web of Conferences, 239, p.17001_1 - 17001_8, 2020/09

https://doi.org/10.1051/epjconf/202023917001

Cross section measurements of Gd(n,) induced by thermal and epithermal neutrons

Mastromarco, M.*; Manna, A.*; Aberle, O.*; Andrzejewski, J.*; Harada, Hideo; Kimura, Atsushi; n_TOF Collaboration*; 116 of others*

European Physical Journal A, 55(1), p.9_1 - 9_20, 2019/01

https://doi.org/10.1140/epja/i2019-12692-7

Radiative neutron capture on Pu in the resonance region at the CERN n_TOF-EAR1 facility

Lerendegui-Marco, J.*; Guerrero, C.*; Mendoza, E.*; Quesada, J. M.*; Eberhardt, K.*; Junghans, A. R.*; Kimura, Atsushi; n_TOF Collaboration*; 126 of others*

Physical Review C, 97(2), p.024605_1 - 024605_21, 2018/02

https://doi.org/10.1103/PhysRevC.97.024605

Small talk about experiments at n_TOF in CERN

Kimura, Atsushi

Kaku Deta Nyusu (Internet), (118), p.36 - 42, 2017/10

http://www.aesj.or.jp/~ndd/ndnews/pdf118/No118-06.pdf

no abstracts in English