Oxford University Press Acta Medica Okayama 2050-3911 2024 10 2024 Study of the Neutrino–Oxygen Cross Sections of the Charged-Current Reaction 16O(ν̄e, e+)16N(0 MeV, 2–) and the Neutral-Current Reaction 16O(ν, ν′)16O(12.97/12.53 MeV, 2–), Producing High-Energy γ Rays 103D01 EN Makoto Sakuda Physics Department, Okayama University Toshio Suzuki Department of Physics, College of Humanities and Sciences, Nihon University Ken'Ichiro Nakazato Faculty of Arts and Science, Kyushu University Hideyuki Suzuki Department of Physics, Faculty of Science and Technology, Tokyo University of Science In our previous work, we discussed the cross section and the detection of 4.4 MeV γ rays produced in the neutrino neutral-current (NC)reaction 16O(ν, ν′)16O(12.97 and 12.53 MeV, 2−) in a water Cherenkov detector at low energy below 100 MeV. In this report, we further investigate both the charged-current reaction 16O(ν¯e, e+)16N(0 MeV, 2−) and the NC reaction16O(ν, ν′)16O(12.97 and 12.53 MeV, 2−), producing high-energy γ rays, in which a more solid identification of the reactions can be applied via the coincidence method. No potential conflict of interest relevant to this article was reported.

Oxford University Press Acta Medica Okayama 2050-3911 2023 6 2023 Angular correlation of the two gamma rays produced in the thermal neutron capture on gadolinium-155 and gadolinium-157 063H01 EN Pierre Goux Department of Physics, Okayama University Franz Glessgen Department of Physics, Okayama University Enrico Gazzola Department of Physics, Okayama University Mandeep Singh Reen Department of Physics, Okayama University William Focillon Département de Physique, École Polytechnique, IN2P3/CNRS Michel Gonin Département de Physique, École Polytechnique, IN2P3/CNRS Tomoyuki Tanaka Department of Physics, Okayama University Kaito Hagiwara Department of Physics, Okayama University Ajmi Ali Department of Physics, Okayama University Takashi Sudo Department of Physics, Okayama University Yusuke Koshio Department of Physics, Okayama University Makoto Sakuda Department of Physics, Okayama University Gianmaria Collazuol INFN Sezione di Padova and Università di Padova, Dipartimento di Fisica Atsushi Kimura Japan Atomic Energy Agency Shoji Nakamura Japan Atomic Energy Agency Nobuyuki Iwamoto Japan Atomic Energy Agency Hideo Harada Japan Atomic Energy Agency Michael Wurm Institut für Physik, Johannes Gutenberg-Universität Mainz 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. No potential conflict of interest relevant to this article was reported.

Oxford University Press Acta Medica Okayama 2050-3911 2023 1 2023 Detection of the 4.4-MeV gamma rays from 16O(ν, ν′)16O(12.97 MeV, 2−) with a water Cherenkov detector in supernova neutrino bursts 013D02 EN Makoto Sakuda Physics Department, Okayama University Toshio Suzuki Department of Physics, College of Humanities and Sciences, Nihon University Mandeep Singh Reen Department of Physics, Akal University Ken'Ichiro Nakazato Faculty of Arts and Science, Kyushu University Hideyuki Suzuki Department of Physics, Faculty of Science and Technology, Tokyo University of Science We first discuss and determine the isospin mixing of the two 2− states (12.53 MeV and 12.97 MeV) of the16O nucleus using inelastic electron scattering data. We then evaluate the cross section of 4.4-MeV γ rays produced in the neutrino neutral-current (NC) reaction 16O(ν, ν′)16O(12.97 MeV, 2−) in a water Cherenkov detector at a low energy, below 100 MeV. The detection of γ rays for Eγ > 5 MeV from the NC reaction 16O(ν, ν′)16O(Ex > 16 MeV, T = 1) with a water Cherenkov detector in supernova neutrino bursts has been proposed and discussed by several authors previously. In this article, we discuss a new NC reaction channel from 16O(12.97 MeV, 2−) producing a 4.4-MeV γ ray, the cross section of which is more robust and even larger at low energy (Eν < 25 MeV) than the NC cross section from 16O(Ex > 16 MeV, T = 1). We also evaluate the number of such events induced by neutrinos from supernova explosion which can be observed by the Super-Kamiokande, an Earth-based 32-kton water Cherenkov detector. No potential conflict of interest relevant to this article was reported.

Oxford University Press Acta Medica Okayama 2050-3911 2020 4 2020 Gamma-ray spectra from thermal neutron capture on gadolinium-155 and natural gadolinium 043D02 EN Tomoyuki Tanaka Department of Physics, Okayama University Kaito Hagiwara Department of Physics, Okayama University Enrico Gazzola Universitá di Padova and INFN, Dipartimento di Fisica Ajmi Ali Department of Physics, Okayama University Iwa Ou Department of Physics, Okayama University Takashi Sudo Department of Physics, Okayama University Pretam Kumar Das Department of Physics, Okayama University Mandeep Singh Reen Department of Physics, Okayama University Rohit Dhir Department of Physics, Okayama University Yusuke Koshio Department of Physics, Okayama University Makoto Sakuda Department of Physics, Okayama University Atsushi Kimura Japan Atomic Energy Agency Shoji Nakamura Japan Atomic Energy Agency Nobuyuki Iwamoto Japan Atomic Energy Agency Hideo Harada Japan Atomic Energy Agency Gianmaria Collazuol Universitá di Padova and INFN, Dipartimento di Fisica Sebastian Lorenz Institut für Physik, Johannes Gutenberg-Universität Mainz Michael Wurm Institut für Physik, Johannes Gutenberg-Universität Mainz William Focillon Département de Physique, École Polytechnique Michel Gonin Département de Physique, École Polytechnique Takatomi Yano Kamioka Observatory, ICRR, University of Tokyo 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. No potential conflict of interest relevant to this article was reported.

Oxford University Press Acta Medica Okayama 2050-3911 2 2019 Gamma-ray spectrum from thermal neutron capture on gadolinium-157 023D01 EN Kaito Hagiwara Department of Physics, Okayama University Takatomi Yano Institute for Cosmic Ray Research, University of Tokyo Tomoyuki Tanaka Department of Physics, Okayama University Mandeep Singh Reen Department of Physics, Okayama University Pretam Kumar Das Department of Physics, Okayama University Sebastian Lorenz Department of Physics, Okayama University Iwa Ou Department of Physics, Okayama University Takashi Sudo Department of Physics, Okayama University Yoshiyuki Yamada Department of Physics, Okayama University Takaaki Mori Department of Physics, Okayama University Tsubasa Kayano Department of Physics, Okayama University Rohit Dhir Department of Physics, Okayama University Yusuke Koshio Department of Physics, Okayama University Makoto Sakuda Department of Physics, Okayama University Atsushi Kimura Japan Atomic Energy Agency Shoji Nakamura Japan Atomic Energy Agency Nobuyuki Iwamoto Japan Atomic Energy Agency Hideo Harada Japan Atomic Energy Agency Michael Wurm Institut für Physik, Johannes Gutenberg-Universität Mainz William Focillon Département de Physique, École Polytechnique Michel Gonin Département de Physique, École Polytechnique Ajmi Ali Department of Physics, Okayama University Gianmaria Collazuol Universitá di Padova and INFN, Dipartimento di Fisica 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. No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 72 5 2005 Electron- and neutrino-nucleus scattering in the impulse approximation regime EN Omar Benher Nicola Farina Hiroki Nakamura Makoto Sakuda Ryoichi Seki <p>A quantitative understanding of the weak nuclear response is a prerequisite for the analyses of neutrino experiments such as K2K and MiniBOONE, which measure energy and angle of the muons produced in neutrino-nucleus interactions in the energy range 0.5-3 GeV and reconstruct the incident neutrino energy to determine neutrino oscillations. In this paper we discuss theoretical calculations of electron- and neutrino-nucleus scattering, carried out within the impulse approximation scheme using realistic nuclear spectral functions. Comparison between electron scattering data and the calculated inclusive cross section of oxygen, at beam energies ranging between 700 and 1200 MeV, show that the Fermi gas model, widely used in the analysis of neutrino oscillation experiments, fails to provide a satisfactory description of the measured cross sections, and inclusion of nuclear dynamics is needed.</p> No potential conflict of interest relevant to this article was reported.

Acta Medica Okayama 94 14 2005 Observation of the acceleration of a single bunch by using the induction device in the kek proton synchrotron EN Ken Takayama Kunio Koseki Kota Torikai Akira Tokuchi Eiji Nakamura Yoshio Arakida Yoshito Shimosaki Masayoshi Wake Tadaaki Kouno Kazuhiko Horioka Susumu Igarashi Taiki Iwashita Atsushi Kawasaki Jun-ichi Kishiro Makoto Sakuda Hikaru Sato Makoto Shiho Masashi Shirakata Tsuyoshi Sueno Takeshi Toyama Masao Watanabe Isao Yamane <p>A single rf bunch in the KEK proton synchrotron was accelerated with an induction acceleration method from the injection energy of 500 MeV to 5 GeV.</p> No potential conflict of interest relevant to this article was reported.