Simple technique for the preparation of uranium-impregnated porous silica particles and their application as working standard particles for analysis of the safeguards environmental samples

Tomita, Jumpei; Tomita, Ryohei; Suzuki, Daisuke; Yasuda, Kenichiro; Miyamoto, Yutaka

Journal of Nuclear Science and Technology, 12 Pages, 2025/09

https://doi.org/10.1080/00223131.2025.2557376

Sensitive U/U isotopic analysis of trace uranium in safeguards environmental samples using multicollector inductively coupled plasma mass spectrometry

Tomita, Jumpei; Tomita, Ryohei; Suzuki, Daisuke; Yasuda, Kenichiro; Miyamoto, Yutaka

Journal of the American Society for Mass Spectrometry, 35(6), p.1178 - 1183, 2024/05

https://doi.org/10.1021/jasms.4c00014

A sensitive analytical technique was investigated in order to determine 10 order of U/U ratio in the sub-ng of uranium using a multi-collector ICP-MS. First, the solution volume was concentrated to one tenth to obtain higher intensities. Next, data acquisition was started from the beginning of the solution uptake and continued until all solution was exhausted. Taking advantage of multi-collector measurement, all data were used with excepting the portion affected by air mixing at the beginning and end of sample introduction. The isotope ratios were calculated from the total counts of each isotope. This technique was applied to U isotope standard (IRMM-184) to measure the 10 order of U/U ratio in the sub-ng of uranium. Measured values were in good agreement with the certified value within the uncertainity (=2). The uncertainties obtained with this new technique (32% on average) were revised to be 10 times smaller than those obtained with the conventionalmethod.

Development of analytical techniques for isotopic composition determination of uranium particles in environmental sample for safeguards with Secondary Ion Mass Spectrometry

Tomita, Ryohei; Tomita, Jumpei; Suzuki, Daisuke; Yasuda, Kenichiro; Miyamoto, Yutaka

Hosha Kagaku, (48), p.1 - 15, 2023/09

Secondary Ion Mass Spectrometry (SIMS) is the method to detect secondary ions produced by the sputtering of primary ions. SIMS is one of effective method to measure isotopic composition of particles containing nuclear material in environmental sample for safeguards. We are a group member of the International Atomic Energy Agency (IAEA)'s network of analytical laboratories and have developed analytical techniques using SIMS and other mass spectrometers for nuclear safeguards. We will introduce the principle of SIMS and analytical techniques developed by our group to measure isotopic composition of uranium particles which having a particle diameter of micron order in environmental sample for safeguards.

In-operando measurement of internal temperature and stress in lithium-ion batteries

Hirano, Tatsumi*; Maeda, Takehiro*; Murata, Tetsuyuki*; Yamaki, Takahiro*; Matsubara, Eiichiro*; Shobu, Takahisa; Shiro, Ayumi*; Yasuda, Ryo*; Takamatsu, Daiko*

SPring-8/SACLA Riyo Kenkyu Seikashu (Internet), 11(1), p.49 - 57, 2023/02

https://doi.org/10.18957/rr.11.1.49

Variation of crystallinity and secondary ion quantity of uranium particles with heating temperature of Sample preparation

Tomita, Ryohei; Tomita, Jumpei; Yomogida, Takumi; Suzuki, Daisuke; Yasuda, Kenichiro; Esaka, Fumitaka; Miyamoto, Yutaka

KEK Proceedings 2022-2, p.108 - 113, 2022/11

https://lib-extopc.kek.jp/preprints/PDF/2022/2225/2225002.pdf

Automated Particle Measurement (APM) is the first measurement of environmental sample for safeguard purpose. APM tells us the number of particles in sample, their enrichment and their location. Precision and accuracy of APM is easily affected by particle condition. We have investigated how influential baking temperature in sample preparation are for uranium secondary ion quantity, uranium hydride generation and particle crystallinity. Our experimental results showed that baking temperature of 800C reduced uranium secondary ion quantity to 33% compared with baking at 350C. Uranium hydride generation ratio of the sample baked at 850C was also 4 times higher than the sample baked at 350C. Baking at 850C raised only crystallinity of uranium particles. Baking sample at too high temperature caused less uranium secondary ion generation and much more uranium hydride generation. It made precision and accuracy of APM worse. In our experiment, baking at 350C is suitable for uranium particles in the safeguards sample.

The Muon linac project at J-PARC

Kondo, Yasuhiro; Kitamura, Ryo; Fuwa, Yasuhiro; Morishita, Takatoshi; Moriya, Katsuhiro; Takayanagi, Tomohiro; Otani, Masashi*; Cicek, E.*; Ego, Hiroyasu*; Fukao, Yoshinori*; et al.

Proceedings of 31st International Linear Accelerator Conference (LINAC 2022) (Internet), p.636 - 641, 2022/09

https://doi.org/10.18429/JACoW-LINAC2022-WE1AA05

The muon linac project for the precise measurement of the muon anomalous magnetic and electric dipole moments, which is currently one of the hottest issues of the elementary particle physics, is in progress at J-PARC. The muons from the J-PARC muon facility are once cooled to room temperature, then accelerated up to 212 MeV with a normalized emittance of 1.5 mm mrad and a momentum spread of 0.1%. Four types of accelerating structures are adopted to obtain the efficient acceleration with a wide beta range from 0.01 to 0.94. The project is moving into the construction phase. We already demonstrated the re-acceleration scheme of the decelerated muons using a 324-MHz RFQ in 2017. The high-power test of the 324-MHz Interdigital H-mode (IH) DTL using a prototype cavity was performed in 2021. The fabrication of the first module of 14 modules of the 1296-MHz Disk and Washer (DAW) CCL will be done to confirm the production process. Moreover, the final design of the travelling wave accelerating structure for the high beta region is also proceeding. In this paper, the recent progress toward the realization of the world first muon linac will be presented.

Fabrication and low-power test of disk-and-washer cavity for muon acceleration

Takeuchi, Yusuke*; Tojo, Junji*; Nakazawa, Yuga*; Kondo, Yasuhiro; Kitamura, Ryo; Morishita, Takatoshi; Cicek, E.*; Ego, Hiroyasu*; Futatsukawa, Kenta*; Kawamura, Naritoshi*; et al.

Proceedings of 13th International Particle Accelerator Conference (IPAC 22) (Internet), p.1534 - 1537, 2022/06

https://doi.org/doi:10.18429/JACoW-IPAC2022-TUPOMS046

The muon g-2/EDM experiment is under preparation at Japan Proton Accelerator Research Complex (J-PARC), and the muon linear accelerator for the experiment is being developed. A Disk-and-Washer (DAW) cavity will be used for the medium-velocity part of the accelerator, and muons will be accelerated from = = 0.3 to 0.7 with the operating frequency of 1.296 GHz. Machining, brazing, and low-power measurements of a prototype cell reflecting the design of the first tank of DAW were performed to identify fabrication problems. Several problems were identified, such as misalignment of washers during brazing, and some measures will be taken in the actual tank fabrication. In this paper, the results of the prototype cell fabrication will be reported.

Design for detecting recycling muon after muon-catalyzed fusion reaction in solid hydrogen isotope target

Okutsu, Kenichi*; Yamashita, Takuma*; Kino, Yasushi*; Nakashima, Ryota*; Miyashita, Konan*; Yasuda, Kazuhiro*; Okada, Shinji*; Sato, Motoyasu*; Oka, Toshitaka; Kawamura, Naritoshi*; et al.

Fusion Engineering and Design, 170, p.112712_1 - 112712_4, 2021/09

https://doi.org/10.1016/j.fusengdes.2021.112712

A muonic molecule which consists of two hydrogen isotope nuclei (deuteron (d) or tritium (t)) and a muon decays immediately via nuclear fusion and the muon will be released as a recycling muon, and start to find another hydrogen isotope nucleus. The reaction cycle continues until the muon ends up its lifetime of 2.2 s. Since the muon does not participate in the nuclear reaction, the reaction is so called a muon catalyzed fusion (CF). The recycling muon has a particular kinetic energy (KE) of the muon molecular orbital when the nuclear reaction occurs. Since the KE is based on the unified atom limit where distance between two nuclei is zero. A precise few-body calculation estimating KE distribution (KED) is also in progress, which could be compared with the experimental results. In the present work, we observed recycling muons after CF reaction.

Time evolution calculation of muon catalysed fusion; Emission of recycling muons from a two-layer hydrogen film

Yamashita, Takuma*; Okutsu, Kenichi*; Kino, Yasushi*; Nakashima, Ryota*; Miyashita, Konan*; Yasuda, Kazuhiro*; Okada, Shinji*; Sato, Motoyasu*; Oka, Toshitaka; Kawamura, Naritoshi*; et al.

Fusion Engineering and Design, 169, p.112580_1 - 112580_5, 2021/08

https://doi.org/10.1016/j.fusengdes.2021.112580

A muon () having 207 times larger mass of electron and the same charge as the electron has been known to catalyze a nuclear fusion between deuteron (d) and triton (t). These two nuclei are bound by and form a muonic hydrogen molecular ion, dt. Due to the short inter-nuclear distance of dt, the nuclear fusion, d +t + n + 17.6 MeV, occurs inside the molecule. This reaction is called muon catalyzed fusion (CF). Recently, the interest on CF is renewed from the viewpoint of applications, such as a source of high-resolution muon beam and mono-energetic neutron beam. In this work, we report a time evolution calculation of CF in a two-layered hydrogen isotope target.

Effects of residual stress on hydrogen embrittlement of a stretch-formed tempered martensitic steel sheet

Nishimura, Hayato*; Hojo, Tomohiko*; Ajita, Saya*; Shibayama, Yuki*; Koyama, Motomichi*; Saito, Hiroyuki*; Shiro, Ayumi*; Yasuda, Ryo*; Shobu, Takahisa; Akiyama, Eiji*

ISIJ International, 61(4), p.1170 - 1178, 2021/04

https://doi.org/10.2355/isijinternational.ISIJINT-2020-492