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Arai, Yoichi; Watanabe, So; Nakahara, Masaumi; Funakoshi, Tomomasa; Hoshino, Takanori; Takahatake, Yoko; Sakamoto, Atsushi; Aihara, Haruka; Hasegawa, Kenta; Yoshida, Toshiki; et al.
Progress in Nuclear Science and Technology (Internet), 7, p.168 - 174, 2025/05
The Japan Atomic Energy Agency (JAEA) has been conducting a project named "Systematic Treatment of RAdioactive liquid waste for Decommissioning (STRAD)" project since 2018 for fundamental and practical studies for treating radioactive liquid wastes with complicated compositions. Fundamental studies have been conducted using genuine liquid wastes accumulated in a hot laboratory of the JAEA called the Chemical Processing Facility (CPF), and treatment procedures for all liquid wastes in CPF were successfully designed on the results obtained. As the next phase of the project, new fundamental and practical studies on primarily organic liquid wastes accumulated in different facilities of JAEA are in progress. This paper reviews the representative achievements of the STRAD project and introduces an overview of ongoing studies.
Yoshida, Junya; Akaishi, Takaya; Fujita, Manami; Hasegawa, Shoichi; Hashimoto, Tadashi; Hosomi, Kenji; Ichikawa, Masaya; Ichikawa, Yudai; Imai, Kenichi*; Kim, S.; et al.
JPS Conference Proceedings (Internet), 33, p.011112_1 - 011112_8, 2021/03
Kim, S. H.*; Ichikawa, Yudai; Sako, Hiroyuki; Hasegawa, Shoichi; Hayakawa, Shuhei*; Nanamura, Takuya*; Sato, Susumu; Tanida, Kiyoshi; Yoshida, Junya; 11 of others*
Nuclear Instruments and Methods in Physics Research A, 940, p.359 - 370, 2019/10
Times Cited Count：5 Percentile：41.52(Instruments & Instrumentation)Ekawa, Hiroyuki; Ashikaga, Sakiko; Hasegawa, Shoichi; Hashimoto, Tadashi; Hayakawa, Shuhei; Hosomi, Kenji; Ichikawa, Yudai; Imai, Kenichi; Kimbara, Shinji*; Nanamura, Takuya; et al.
Progress of Theoretical and Experimental Physics (Internet), 2019(2), p.021D02_1 - 021D02_11, 2019/02
Times Cited Count：30 Percentile：83.20(Physics, Multidisciplinary)
hyperon capture at rest in nuclear emulsionTheint, A. M. M.*; Ekawa, Hiroyuki; Yoshida, Junya; 7 of others*
Progress of Theoretical and Experimental Physics (Internet), 2019(2), p.021D01_1 - 021D01_10, 2019/02
Times Cited Count：6 Percentile：42.94(Physics, Multidisciplinary)Kimbara, Shinji*; Ekawa, Hiroyuki; Hayakawa, Shuhei; Yoshida, Junya; 12 of others*
Progress of Theoretical and Experimental Physics (Internet), 2019(1), p.011H01_1 - 011H01_9, 2019/01
Times Cited Count：5 Percentile：37.91(Physics, Multidisciplinary)A development has been achieved in the identification method of the charges 1 to 5 of nuclides from the decay of double hypernuclei to be uniquely recognized by their nuclear species. The method is basically the measurement of track volume by the widths, depths, and angles of tracks of exposed nuclei of 
H, 
He, 
Li, 
Be, and 
B in nuclear emulsion at Riken Projectile-fragment Separator of RIKEN Radioactive Isotope Beam Factory. After their calibration by 
particles, we obtained a quadric function to present a unified recognition of tracks with volume ratios of five nuclei to the particles. The function in the emulsion has been applied to a candidate event of a 
hypernucleus for identification of the production and decay processes. We succeeded in recognizing a daughter nuclear fragment of a single-
hypernucleus as 
He with a likelihood ratio of 0.9; the process was then uniquely identified as 
+ 
N 
Be + 
He + 
.
Kawasaki, Masatsugu; Nakajima, Junya; Yoshida, Keisuke; Kato, Saori; Nishino, Sho; Nozaki, Teo; Nakagawa, Masahiro; Tsunoda, Junichi; Sugaya, Yuki; Hasegawa, Rie; et al.
JAEA-Data/Code 2017-004, 57 Pages, 2017/03
JAEA-Data-Code-2017-004.pdf:2.34MB
In emergency situation of nuclear facilities, we need to estimate the radiation dose due to radiation and radioactivity to grasp the influence range of the accident in the early stage. Therefore, we prepare the case studies of dose assessment for public exposure dose and personal exposure dose and contribute them to emergency procedures. This document covers about accidents of nuclear facilities in Nuclear Science Research Institute and past accident of nuclear power plant, and it can be used for inheritance of techniques of emergency dose assessment.
Yamada, Katsunori; Fujii, Katsutoshi; Kanda, Hiroshi; Higashi, Daisuke; Kobayashi, Toshiaki; Nakagawa, Masahiro; Fukami, Tomoyo; Yoshida, Keisuke; Ueno, Yumi; Nakajima, Junya; et al.
JAEA-Review 2013-033, 51 Pages, 2013/12
JAEA-Review-2013-033.pdf:2.73MB
After the accident at Fukushima Dai-ichi Nuclear Power Plant, various numerical criteria relevant to radiation protection were defined. We surveyed these criteria through internet. As a result of survey, the following 13 items were identified: (1) criteria for taking stable iodine tablets, (2) criteria for the screening of surface contamination, (3) evacuation area, sheltering area, etc., (4) activity concentrations in food, drinking water, etc., (5) dose limit for radiation workers engaged in emergency work, (6) guideline levels of radioactive substances in bathing areas, (7) criteria for use of school buildings and schoolyards, (8) restriction on planting rice, (9) acceptable activity concentrations in feedstuff, (10) acceptable activity concentrations in compost, (11) criteria for export containers and ships, (12) criteria for contaminated waste, (13) standards for radiation workers engaged in decontamination work. In this report, the basis of and issues on these criteria are summarized.
Shiraishi, Junya; Yoshida, Zensho*; Furukawa, Masaru*
Astrophysical Journal, 697(1), p.100 - 105, 2009/03
Times Cited Count：5 Percentile：17.30(Astronomy & Astrophysics)A thin disk accompanied by spindle-like jet, created commonly near massive central objects, exhibits a topologically singular aspect when viewed from an ideal macroscopic theory. The accreting inflow and jet's outflow are "singular perturbation" on the ambient Keplerian rotation, which are generated by some non-ideal higher-order (in the order of derivatives) effect. The Hall effect can generate such a structure in a weakly ionized plasma of a protostellar disk. Numerical estimate of the characteristic length scale defined by the singular perturbation justifies the precedence of the Hall effect.
Katayama, Hisato*; Kitamura, Harushige*; Mori, Mari*; Nakagawa, Junya*; Yoshida, Takahiro*; Kawai, Toshihiko*; Hase, Yoshihiro; Tanaka, Atsushi
JAEA-Review 2006-042, JAEA Takasaki Annual Report 2005, P. 94, 2007/02
no abstracts in English
Yoshida, Junya; Hayakawa, Shuhei; Ekawa, Hiroyuki*; Yoshimoto, Masahiro*; Kasagi, Ayumi*; Lin, P. M.*; Nyaw, A. N. L.*; Nakazawa, Kazuma*
no journal, ,
J-PARC E07 is an experiment with the photographic emulsion technique to detect 10 times higher statistics of double hypernuclei compared to the past experiments. This experiment aims to obtain quantitative data on - and -nucleon interaction, by the mass measurement of various double hypernuclei. As of July 2019, we have scanned about 53% of 1300 emulsion sheets at least once and detected about 30 candidate events of double hypernuclei. We start a study of the branching ratio of the decay mode with the accumulating data. However, the detection efficiency is about half of the designed value. It is due to the rugged surface position of emulsion module. We are developing the correction method to reconstruct its original geometry by using proton tracks which punch through SSD and emulsion sheets.
-N interaction by measurement of twin hypernuclei with hybrid emulsion method at J-PARCHayakawa, Shuhei; Yoshida, Junya
no journal, ,
The studies of hyperon-nucleon and hyperon-hyperon interactions are necessary for the understanding of general baryon-baryon interaction. Even in the 
= -1 sector such as 
and 
, the available data is limited. As for the = -2 sector such as 
and 
, there are few experimental data. The J-PARC E07 experiment was performed to investigate = -2 hypernuclei at J-PARC K1.8 beam line. Using a K- meson beam with the momentum of 1.81 GeV/c, - hyperons are produced in the quasi-free 
, K
- reaction at a diamond target. A method using combined information between two spectrometers and nuclear emulsion, called hybrid emulsion method, was conducted by using silicon-strip detectors and one hundred eighteen emulsion modules. A twin hypernuclear event, named IBUKI event, was observed with a newly developed scanning system. At the - capture point, two hypernuclei of 
Be and He were the most likely to be produced by the conservation laws of energy and momentum. The reaction process of the IBUKI event was identified as - + N Be + He. The binding energy of - + N system was determined to be 1.27 
0.21 MeV. From the consideration of an excited state, the energy level for Be was interpreted to be the ground state (2-) or the other state of the spin doublet (1-). The IBUKI event was the first event whose binding energy was determined with a little ambiguity. The binding energy indicates a bound state of the -N system by an attractive interaction. In this talk, we would like to report the above result of the IBUKI event.
Yoshida, Junya
no journal, ,
Double hypernuclei and hypernuclei, collectively called "double hypernuclei", have come to play important roles in hadron nuclear physics as valuable information sources of baryon-baryon interaction. The most effective method to investigate them is event-by-event analysis with photographic emulsion sheets. An emulsion experiment to detect double hypernuclei has been performed in the J-PARC hadron facility in 2016-17. By this experiment, quantitative data on or 
interaction in a nucleus are being accumulated successfully. A new nuclide of double hypernucleus, 
Be, was observed. Several other interesting events have been found and further event search is going on.
Yoshida, Junya
no journal, ,
J-PARC E07, the largest experiment with Double Lambda hypernucleus thus far at J-PARC was designed and performed. Double hypernuclei, rare nuclei containing 2 Lambda particles is one of the important subjects in modern hadron nuclear physics. The experiment is unique in that photographic emulsion sheets are employed as the main detector for Double hypernuclei. We performed the physics-run in the J-PARC hadron facility in 2016-17. One of the observed events was identified as a beryllium 11 double Lambda. We measured the strength of Lambda-Lambda interaction through the event. Moreover, we detected several hypernuclei events which suggest multiple bound levels of particle in the nucleus. Further event search is ongoing.
Yoshida, Junya; Hayakawa, Shuhei; Ekawa, Hiroyuki*; Yoshimoto, Masahiro*; Kasagi, Ayumi*; Lin, P. M.*; Nyaw, A. N. L.*; Nakazawa, Kazuma*
no journal, ,
J-PARC E07 is an experiment to detect double hypernuclear events with the largest statistics in the past using photographic emulsion sheets. Experimental data on - and -nucleon interaction, are obtained by mass measurements of various double hypernuclei. The main step in the analysis of this experiment is the tracking of 
particles in emulsion sheets under optical microscopes. We expect to complete the first period analysis of all the sheets by March 2020. The number of events obtained in the first period is about 40% of the planned yield. The remaining events will be detected in the second search in the near future. It is considered that the cause of missing particles was that the prediction of the incident position of particles was incorrect due to poor flatness of the uppermost stream sheet. Therefore, we are trying to correct the surface position and find the missing particles.
Yoshida, Hiroko*; Nomura, Naoki*; Kono, Takahiko; Sakoda, Akihiro; Kuroda, Yujiro*; Naito, Wataru*; Hirota, Seiko*; Kudo, Shinichi*; Takahara, Shogo; Etani, Reo*; et al.
no journal, ,
The WG has translated the "Practical Guidance for Engagement with the Public on Radiation and Risk" ("IRPA Guidance") issued by the International Radiation Protection Association ("IRPA") to its member societies in 2020. "Practical Guidance for Engagement with the Public on Radiation and Risk" (hereinafter referred to as "IRPA Guidance") published by the International Radiological Protection Association (hereinafter referred to as "IRPA") in 2020 for its member societies, and to provide the information to radiation protection experts and other interested.
Yoshida, Hiroko*; Nomura, Naoki*; Kono, Takahiko; Sakoda, Akihiro; Kuroda, Yujiro*; Naito, Wataru*; Hirota, Seiko*; Kudo, Shinichi*; Kawaguchi, Isao*; Etani, Reo*; et al.
no journal, ,
The WG has translated the "Practical Guidance for Engagement with the Public on Radiation and Risk" ("IRPA Guidance") issued by the International Radiation Protection Association ("IRPA") to its member societies in 2020. "The content of the IRPA guidance was presented at a symposium organized by the Health Physics Society of Japan in June 2020. The content of the IRPA guidance was presented at the Health Physics Society planning symposium held in June 2020, where many experts attended and provided feedback. In this planning session, we will focus on public engagement and related specific examples and situations related to public engagement.
Takada, Chie; Nakano, Masanao; Munakata, Masahiro; Yoshida, Tadayoshi; Yokosuka, Yoshiyuki; Yamada, Junya; Maeda, Eita; Watanabe, Yuki; Tomioka, Akifumi; Momose, Takumaro
no journal, ,
no abstracts in English
Matsumoto, Saori; Kuramochi, Ryo*; Shimizu, Koki; Sato, Junya; Taniguchi, Takumi; Kuroki, Ryoichiro; Okada, Takashi; Yoshida, Yukihiko; Osugi, Takeshi
no journal, ,
no abstracts in English
Hiraki, Yoshihisa; Sato, Junya; Chaerun, R. I.; Niu, X.*; Elakneswaran, Y.*; Yoshida, Yukihiko; Osugi, Takeshi
no journal, ,
