start-ver=1.4 cd-journal=joma no-vol=2025 cd-vols= no-issue=1 article-no= start-page=013C01 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2024 dt-pub=20241226 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Modification on Thermal Motion in Geant4 for Neutron Capture Simulation in Gadolinium Loaded Water en-subtitle= kn-subtitle= en-abstract= kn-abstract=Neutron tagging is a fundamental technique for electron anti-neutrino detection via the inverse beta decay channel. A reported discrepancy in neutron detection efficiency between observational data and simulation predictions prompted an investigation into neutron capture modeling in Geant4. The study revealed that an overestimation of the thermal motion of hydrogen atoms in Geant4 impacts the fraction of captured nuclei. By manually modifying the Geant4 implementation, the simulation results align with calculations based on evaluated nuclear data and show good agreement with observables derived from the SK-Gd data. en-copyright= kn-copyright= en-aut-name=HinoY. en-aut-sei=Hino en-aut-mei=Y. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=AbeK. en-aut-sei=Abe en-aut-mei=K. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=AsakaR. en-aut-sei=Asaka en-aut-mei=R. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=HanS. en-aut-sei=Han en-aut-mei=S. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=HaradaM. en-aut-sei=Harada en-aut-mei=M. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=IshitsukaM. en-aut-sei=Ishitsuka en-aut-mei=M. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=ItoH. en-aut-sei=Ito en-aut-mei=H. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=IzumiyamaS. en-aut-sei=Izumiyama en-aut-mei=S. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=KanemuraY. en-aut-sei=Kanemura en-aut-mei=Y. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= en-aut-name=KoshioY. en-aut-sei=Koshio en-aut-mei=Y. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=10 ORCID= en-aut-name=NakanishiF. en-aut-sei=Nakanishi en-aut-mei=F. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=11 ORCID= en-aut-name=SekiyaH. en-aut-sei=Sekiya en-aut-mei=H. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=12 ORCID= en-aut-name=YanoT. en-aut-sei=Yano en-aut-mei=T. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=13 ORCID= affil-num=1 en-affil=Department of Physics, Okayama University kn-affil= affil-num=2 en-affil=Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo kn-affil= affil-num=3 en-affil=Department of Physics, Faculty of Science and Technology, Tokyo University of Science kn-affil= affil-num=4 en-affil=Research Center for Cosmic Neutrinos, Institute for Cosmic Ray Research, University of Tokyo kn-affil= affil-num=5 en-affil=Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo kn-affil= affil-num=6 en-affil=Department of Physics, Faculty of Science and Technology, Tokyo University of Science kn-affil= affil-num=7 en-affil=Department of Physics, Faculty of Science and Technology, Tokyo University of Science kn-affil= affil-num=8 en-affil=Department of Physics, Tokyo Institute of Technology kn-affil= affil-num=9 en-affil=Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo kn-affil= affil-num=10 en-affil=Department of Physics, Okayama University kn-affil= affil-num=11 en-affil=Department of Physics, Okayama University kn-affil= affil-num=12 en-affil=Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo kn-affil= affil-num=13 en-affil=Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo kn-affil= END start-ver=1.4 cd-journal=joma no-vol=965 cd-vols= no-issue=1 article-no= start-page=91 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2024 dt-pub=20240410 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Supernova Burst and Diffuse Supernova Neutrino Background Simulator for Water Cherenkov Detectors en-subtitle= kn-subtitle= en-abstract= kn-abstract=If a Galactic core-collapse supernova explosion occurs in the future, it will be critical to rapidly alert the community to the direction of the supernova by utilizing neutrino signals in order to enable the initiation of follow-up optical observations. In addition, there is anticipation that observation of the diffuse supernova neutrino background will yield discoveries in the near future, given that experimental upper limits are approaching theoretical predictions. We have developed a new supernova event simulator for water Cherenkov neutrino detectors, such as the highly sensitive Super-Kamiokande. This simulator calculates the neutrino interaction in water for two simulation purposes, individual core-collapse supernova bursts and diffuse supernova neutrino background. Based on this simulator, we can evaluate the precision in determining the location of supernovae and estimate the expected number of events related to the diffuse supernova neutrino background in Super-Kamiokande. In this paper, we describe the basic structure of the simulator and its demonstration. en-copyright= kn-copyright= en-aut-name=NakanishiFumi en-aut-sei=Nakanishi en-aut-mei=Fumi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=IzumiyamaShota en-aut-sei=Izumiyama en-aut-mei=Shota kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=HaradaMasayuki en-aut-sei=Harada en-aut-mei=Masayuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=KoshioYusuke en-aut-sei=Koshio en-aut-mei=Yusuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= affil-num=1 en-affil=Department of Physics, Okayama University kn-affil= affil-num=2 en-affil=Department of Physics, Tokyo Institute of Technology kn-affil= affil-num=3 en-affil=Department of Physics, Okayama University kn-affil= affil-num=4 en-affil=Department of Physics, Okayama University kn-affil= END start-ver=1.4 cd-journal=joma no-vol=2023 cd-vols= no-issue=6 article-no= start-page=063H01 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2023 dt-pub=20230505 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Angular correlation of the two gamma rays produced in the thermal neutron capture on gadolinium-155 and gadolinium-157 en-subtitle= kn-subtitle= en-abstract= kn-abstract=The ANNRI-Gd collaboration studied in detail the single gamma-ray spectrum produced from the thermal neutron capture on Gd-155 and Gd-157 in our previous publications. Gadolinium targets were exposed to a neutron beam provided by the Japan Spallation Neutron Source (JSNS) in J-PARC, Japan. In the present analysis, one new additional coaxial germanium crystal was used in combination with the 14 germanium crystals in the cluster detectors to study the angular correlation of the two gamma rays emitted in the same neutron capture. We present for the first time angular correlation functions for two gamma rays produced during the electromagnetic cascade transitions in the (n, gamma) reactions on Gd-155 and Gd-157. As expected, we observe mild angular correlations for the strong, but rare transitions from the resonance state to the two energy levels of known spin-parities. Contrariwise, we observe negligibly small angular correlations for arbitrary pairs of two gamma rays produced in the majority of cascade transitions from the resonance state to the dense continuum states. en-copyright= kn-copyright= en-aut-name=GouxPierre en-aut-sei=Goux en-aut-mei=Pierre kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=GlessgenFranz en-aut-sei=Glessgen en-aut-mei=Franz kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=GazzolaEnrico en-aut-sei=Gazzola en-aut-mei=Enrico kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=ReenMandeep Singh en-aut-sei=Reen en-aut-mei=Mandeep Singh kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=FocillonWilliam en-aut-sei=Focillon en-aut-mei=William kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=GoninMichel en-aut-sei=Gonin en-aut-mei=Michel kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=TanakaTomoyuki en-aut-sei=Tanaka en-aut-mei=Tomoyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=HagiwaraKaito en-aut-sei=Hagiwara en-aut-mei=Kaito kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=AliAjmi en-aut-sei=Ali en-aut-mei=Ajmi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= en-aut-name=SudoTakashi en-aut-sei=Sudo en-aut-mei=Takashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=10 ORCID= en-aut-name=KoshioYusuke en-aut-sei=Koshio en-aut-mei=Yusuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=11 ORCID= en-aut-name=SakudaMakoto en-aut-sei=Sakuda en-aut-mei=Makoto kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=12 ORCID= en-aut-name=CollazuolGianmaria en-aut-sei=Collazuol en-aut-mei=Gianmaria kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=13 ORCID= en-aut-name=KimuraAtsushi en-aut-sei=Kimura en-aut-mei=Atsushi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=14 ORCID= en-aut-name=NakamuraShoji en-aut-sei=Nakamura en-aut-mei=Shoji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=15 ORCID= en-aut-name=IwamotoNobuyuki en-aut-sei=Iwamoto en-aut-mei=Nobuyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=16 ORCID= en-aut-name=HaradaHideo en-aut-sei=Harada en-aut-mei=Hideo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=17 ORCID= en-aut-name=WurmMichael en-aut-sei=Wurm en-aut-mei=Michael kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=18 ORCID= affil-num=1 en-affil=Department of Physics, Okayama University kn-affil= affil-num=2 en-affil=Department of Physics, Okayama University kn-affil= affil-num=3 en-affil=Department of Physics, Okayama University kn-affil= affil-num=4 en-affil=Department of Physics, Okayama University kn-affil= affil-num=5 en-affil=Département de Physique, École Polytechnique, IN2P3/CNRS kn-affil= affil-num=6 en-affil=Département de Physique, École Polytechnique, IN2P3/CNRS kn-affil= affil-num=7 en-affil=Department of Physics, Okayama University kn-affil= affil-num=8 en-affil=Department of Physics, Okayama University kn-affil= affil-num=9 en-affil=Department of Physics, Okayama University kn-affil= affil-num=10 en-affil=Department of Physics, Okayama University kn-affil= affil-num=11 en-affil=Department of Physics, Okayama University kn-affil= affil-num=12 en-affil=Department of Physics, Okayama University kn-affil= affil-num=13 en-affil=INFN Sezione di Padova and Università di Padova, Dipartimento di Fisica kn-affil= affil-num=14 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=15 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=16 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=17 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=18 en-affil=Institut für Physik, Johannes Gutenberg-Universität Mainz kn-affil= END start-ver=1.4 cd-journal=joma no-vol=2020 cd-vols= no-issue=4 article-no= start-page=043D02 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20200413 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Gamma-ray spectra from thermal neutron capture on gadolinium-155 and natural gadolinium en-subtitle= kn-subtitle= en-abstract= kn-abstract=Natural gadolinium is widely used for its excellent thermal neutron capture cross section, because of its two major isotopes: Gd-155 and Gd-157. We measured the gamma-ray spectra produced from the thermal neutron capture on targets comprising a natural gadolinium film and enriched Gd-155 (in Gd2O3 powder) in the energy range from 0.11 MeV to 8.0 MeV, using the ANNRI germanium spectrometer at MLF, J-PARC. The freshly analyzed data of the Gd-155(n,gamma) reaction are used to improve our previously developed model (ANNRI-Gd model) for the Gd-157(n,gamma) reaction [K. Hagiwara et al. [ANNRI-Gd Collaboration], Prog. Theor. Exp. Phys. 2019, 023D01 (2019)], and its performance confirmed with the independent data from the Gd-nat(n,gamma) reaction. This article completes the development of an efficient Monte Carlo model required to simulate and analyze particle interactions involving the thermal neutron captures on gadolinium in any relevant future experiments. en-copyright= kn-copyright= en-aut-name=TanakaTomoyuki en-aut-sei=Tanaka en-aut-mei=Tomoyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=HagiwaraKaito en-aut-sei=Hagiwara en-aut-mei=Kaito kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=GazzolaEnrico en-aut-sei=Gazzola en-aut-mei=Enrico kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=AliAjmi en-aut-sei=Ali en-aut-mei=Ajmi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=OuIwa en-aut-sei=Ou en-aut-mei=Iwa kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=SudoTakashi en-aut-sei=Sudo en-aut-mei=Takashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=DasPretam Kumar en-aut-sei=Das en-aut-mei=Pretam Kumar kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=ReenMandeep Singh en-aut-sei=Reen en-aut-mei=Mandeep Singh kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=DhirRohit en-aut-sei=Dhir en-aut-mei=Rohit kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= en-aut-name=KoshioYusuke en-aut-sei=Koshio en-aut-mei=Yusuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=10 ORCID= en-aut-name=SakudaMakoto en-aut-sei=Sakuda en-aut-mei=Makoto kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=11 ORCID= en-aut-name=KimuraAtsushi en-aut-sei=Kimura en-aut-mei=Atsushi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=12 ORCID= en-aut-name=NakamuraShoji en-aut-sei=Nakamura en-aut-mei=Shoji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=13 ORCID= en-aut-name=IwamotoNobuyuki en-aut-sei=Iwamoto en-aut-mei=Nobuyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=14 ORCID= en-aut-name=HaradaHideo en-aut-sei=Harada en-aut-mei=Hideo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=15 ORCID= en-aut-name=CollazuolGianmaria en-aut-sei=Collazuol en-aut-mei=Gianmaria kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=16 ORCID= en-aut-name=LorenzSebastian en-aut-sei=Lorenz en-aut-mei=Sebastian kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=17 ORCID= en-aut-name=WurmMichael en-aut-sei=Wurm en-aut-mei=Michael kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=18 ORCID= en-aut-name=FocillonWilliam en-aut-sei=Focillon en-aut-mei=William kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=19 ORCID= en-aut-name=GoninMichel en-aut-sei=Gonin en-aut-mei=Michel kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=20 ORCID= en-aut-name=YanoTakatomi en-aut-sei=Yano en-aut-mei=Takatomi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=21 ORCID= affil-num=1 en-affil=Department of Physics, Okayama University kn-affil= affil-num=2 en-affil=Department of Physics, Okayama University kn-affil= affil-num=3 en-affil=Universitá di Padova and INFN, Dipartimento di Fisica kn-affil= affil-num=4 en-affil=Department of Physics, Okayama University kn-affil= affil-num=5 en-affil=Department of Physics, Okayama University kn-affil= affil-num=6 en-affil=Department of Physics, Okayama University kn-affil= affil-num=7 en-affil=Department of Physics, Okayama University kn-affil= affil-num=8 en-affil=Department of Physics, Okayama University kn-affil= affil-num=9 en-affil=Department of Physics, Okayama University kn-affil= affil-num=10 en-affil=Department of Physics, Okayama University kn-affil= affil-num=11 en-affil=Department of Physics, Okayama University kn-affil= affil-num=12 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=13 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=14 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=15 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=16 en-affil=Universitá di Padova and INFN, Dipartimento di Fisica kn-affil= affil-num=17 en-affil=Institut für Physik, Johannes Gutenberg-Universität Mainz kn-affil= affil-num=18 en-affil=Institut für Physik, Johannes Gutenberg-Universität Mainz kn-affil= affil-num=19 en-affil=Département de Physique, École Polytechnique kn-affil= affil-num=20 en-affil=Département de Physique, École Polytechnique kn-affil= affil-num=21 en-affil=Kamioka Observatory, ICRR, University of Tokyo kn-affil= END start-ver=1.4 cd-journal=joma no-vol=6 cd-vols= no-issue=6 article-no= start-page=80 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2020 dt-pub=20200605 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Observation of Atmospheric Neutrinos en-subtitle= kn-subtitle= en-abstract= kn-abstract=In 1998, the Super-Kamiokande discovered neutrino oscillation using atmospheric neutrino anomalies. It was the first direct evidence of neutrino mass and the first phenomenon to be discovered beyond the standard model of particle physics. Recently, more precise measurements of neutrino oscillation parameters using atmospheric neutrinos have been achieved by several detectors, such as Super-Kamiokande, IceCube, and ANTARES. In addition, precise predictions and measurements of atmospheric neutrino flux have been performed. This paper presents the history, current status, and future prospects of the atmospheric neutrino observation. en-copyright= kn-copyright= en-aut-name=KoshioYusuke en-aut-sei=Koshio en-aut-mei=Yusuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= affil-num=1 en-affil=Experimental Particle Physics Group, Department of Physics, Okayama University kn-affil= en-keyword=neutrino oscillation kn-keyword=neutrino oscillation en-keyword=atmospheric neutrino kn-keyword=atmospheric neutrino END start-ver=1.4 cd-journal=joma no-vol= cd-vols= no-issue=2 article-no= start-page=023D01 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2019 dt-pub=20190222 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Gamma-ray spectrum from thermal neutron capture on gadolinium-157 en-subtitle= kn-subtitle= en-abstract= kn-abstract=We have measured the -ray energy spectrum from the thermal neutron capture, Gd, on an enriched Gd target (GdO) in the energy range from 0.11 MeV up to about 8 MeV. The target was placed inside the germanium spectrometer of the ANNRI detector at J-PARC and exposed to a neutron beam from the Japan Spallation Neutron Source (JSNS). Radioactive sources (Co, Cs, and Eu) and the Cl(,) reaction were used to determine the spectrometers detection efficiency for rays at energies from 0.3 to 8.5 MeV. Using a Geant4-based Monte Carlo simulation of the detector and based on our data, we have developed a model to describe the -ray spectrum from the thermal Gd(,) reaction. While we include the strength information of 15 prominent peaks above 5 MeV and associated peaks below 1.6 MeV from our data directly into the model, we rely on the theoretical inputs of nuclear level density and the photon strength function of Gd to describe the continuum -ray spectrum from the Gd(,) reaction. Our model combines these two components. The results of the comparison between the observed -ray spectra from the reaction and the model are reported in detail. en-copyright= kn-copyright= en-aut-name=HagiwaraKaito en-aut-sei=Hagiwara en-aut-mei=Kaito kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=YanoTakatomi en-aut-sei=Yano en-aut-mei=Takatomi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=TanakaTomoyuki en-aut-sei=Tanaka en-aut-mei=Tomoyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=ReenMandeep Singh en-aut-sei=Reen en-aut-mei=Mandeep Singh kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=DasPretam Kumar en-aut-sei=Das en-aut-mei=Pretam Kumar kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=LorenzSebastian en-aut-sei=Lorenz en-aut-mei=Sebastian kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=OuIwa en-aut-sei=Ou en-aut-mei=Iwa kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=SudoTakashi en-aut-sei=Sudo en-aut-mei=Takashi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=YamadaYoshiyuki en-aut-sei=Yamada en-aut-mei=Yoshiyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= en-aut-name=MoriTakaaki en-aut-sei=Mori en-aut-mei=Takaaki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=10 ORCID= en-aut-name=KayanoTsubasa en-aut-sei=Kayano en-aut-mei=Tsubasa kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=11 ORCID= en-aut-name=DhirRohit en-aut-sei=Dhir en-aut-mei=Rohit kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=12 ORCID= en-aut-name=KoshioYusuke en-aut-sei=Koshio en-aut-mei=Yusuke kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=13 ORCID= en-aut-name=SakudaMakoto en-aut-sei=Sakuda en-aut-mei=Makoto kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=14 ORCID= en-aut-name=KimuraAtsushi en-aut-sei=Kimura en-aut-mei=Atsushi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=15 ORCID= en-aut-name=NakamuraShoji en-aut-sei=Nakamura en-aut-mei=Shoji kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=16 ORCID= en-aut-name=IwamotoNobuyuki en-aut-sei=Iwamoto en-aut-mei=Nobuyuki kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=17 ORCID= en-aut-name=HaradaHideo en-aut-sei=Harada en-aut-mei=Hideo kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=18 ORCID= en-aut-name=WurmMichael en-aut-sei=Wurm en-aut-mei=Michael kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=19 ORCID= en-aut-name=FocillonWilliam en-aut-sei=Focillon en-aut-mei=William kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=20 ORCID= en-aut-name=GoninMichel en-aut-sei=Gonin en-aut-mei=Michel kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=21 ORCID= en-aut-name=AliAjmi en-aut-sei=Ali en-aut-mei=Ajmi kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=22 ORCID= en-aut-name=CollazuolGianmaria en-aut-sei=Collazuol en-aut-mei=Gianmaria kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=23 ORCID= affil-num=1 en-affil=Department of Physics, Okayama University kn-affil= affil-num=2 en-affil=Institute for Cosmic Ray Research, University of Tokyo kn-affil= affil-num=3 en-affil=Department of Physics, Okayama University kn-affil= affil-num=4 en-affil=Department of Physics, Okayama University kn-affil= affil-num=5 en-affil=Department of Physics, Okayama University kn-affil= affil-num=6 en-affil=Department of Physics, Okayama University kn-affil= affil-num=7 en-affil=Department of Physics, Okayama University kn-affil= affil-num=8 en-affil=Department of Physics, Okayama University kn-affil= affil-num=9 en-affil=Department of Physics, Okayama University kn-affil= affil-num=10 en-affil=Department of Physics, Okayama University kn-affil= affil-num=11 en-affil=Department of Physics, Okayama University kn-affil= affil-num=12 en-affil=Department of Physics, Okayama University kn-affil= affil-num=13 en-affil=Department of Physics, Okayama University kn-affil= affil-num=14 en-affil=Department of Physics, Okayama University kn-affil= affil-num=15 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=16 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=17 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=18 en-affil=Japan Atomic Energy Agency kn-affil= affil-num=19 en-affil=Institut für Physik, Johannes Gutenberg-Universität Mainz kn-affil= affil-num=20 en-affil=Département de Physique, École Polytechnique kn-affil= affil-num=21 en-affil=Département de Physique, École Polytechnique kn-affil= affil-num=22 en-affil=Department of Physics, Okayama University kn-affil= affil-num=23 en-affil=Universitá di Padova and INFN, Dipartimento di Fisica kn-affil= END start-ver=1.4 cd-journal=joma no-vol= cd-vols= no-issue=6 article-no= start-page=063H03 end-page= dt-received= dt-revised= dt-accepted= dt-pub-year=2019 dt-pub=20190629 dt-online= en-article= kn-article= en-subject= kn-subject= en-title= kn-title=Development of a method for measuring rare earth elements in the environment for future experiments with gadolinium-loaded detectors en-subtitle= kn-subtitle= en-abstract= kn-abstract=Demand to use gadolinium (Gd) in detectors is increasing in the field of elementary particle physics, especially in neutrino measurements and dark matter searches. Large amounts of Gd are used in these experiments. To assess the impact of Gd on the environment it is becoming important to measure the baseline concentrations of Gd. Such measurement, however, is not easy due to interference by other elements. In this paper a method for measuring the concentrations of rare earth elements, including Gd, is proposed. In the method, inductively coupled plasma-mass spectrometry is utilized after collecting the dissolved elements in chelating resin. Results of the ability to detect anomalous concentrations of rare earth elements in river water samples in the Kamioka and Toyama areas are also reported. en-copyright= kn-copyright= en-aut-name=ItoS. en-aut-sei=Ito en-aut-mei=S. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=1 ORCID= en-aut-name=OkadaT. en-aut-sei=Okada en-aut-mei=T. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=2 ORCID= en-aut-name=TakakuY. en-aut-sei=Takaku en-aut-mei=Y. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=3 ORCID= en-aut-name=HaradaM. en-aut-sei=Harada en-aut-mei=M. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=4 ORCID= en-aut-name=IkedaM. en-aut-sei=Ikeda en-aut-mei=M. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=5 ORCID= en-aut-name=KishimotoY. en-aut-sei=Kishimoto en-aut-mei=Y. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=6 ORCID= en-aut-name=KoshioY. en-aut-sei=Koshio en-aut-mei=Y. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=7 ORCID= en-aut-name=NakahataM. en-aut-sei=Nakahata en-aut-mei=M. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=8 ORCID= en-aut-name=NakajimaY. en-aut-sei=Nakajima en-aut-mei=Y. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=9 ORCID= en-aut-name=SekiyaH. en-aut-sei=Sekiya en-aut-mei=H. kn-aut-name= kn-aut-sei= kn-aut-mei= aut-affil-num=10 ORCID= affil-num=1 en-affil=Okayama University, Faculty of Science kn-affil= affil-num=2 en-affil=Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo kn-affil= affil-num=3 en-affil=Institute for Environmental Sciences, Department of Radioecology kn-affil= affil-num=4 en-affil=Okayama University, Faculty of Science kn-affil= affil-num=5 en-affil=Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo kn-affil= affil-num=6 en-affil=Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo kn-affil= affil-num=7 en-affil=Okayama University, Faculty of Science kn-affil= affil-num=8 en-affil=Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo kn-affil= affil-num=9 en-affil=Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo kn-affil= affil-num=10 en-affil= kn-affil= END