R. Okazaki
A5070486548- Neutrino Physics Research
- Astrophysics and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Plasma Diagnostics and Applications
- Geology and Paleoclimatology Research
- Laser-induced spectroscopy and plasma
- Magnetic confinement fusion research
- Particle accelerators and beam dynamics
- Nuclear Physics and Applications
- Dark Matter and Cosmic Phenomena
- Nuclear reactor physics and engineering
- Radiation Detection and Scintillator Technologies
- Climate change and permafrost
- Fusion materials and technologies
- Atmospheric Ozone and Climate
- Soil and Unsaturated Flow
- Quantum Chromodynamics and Particle Interactions
- Chemistry and Chemical Engineering
- Solar and Space Plasma Dynamics
- Metallurgical Processes and Thermodynamics
- Rangeland and Wildlife Management
- Metallurgy and Material Forming
- Inorganic and Organometallic Chemistry
- Microstructure and Mechanical Properties of Steels
- Synthesis of β-Lactam Compounds
Keio University
2023-2025
Kavli Institute for the Physics and Mathematics of the Universe
2024
Institute for Cosmic Ray Research
2024
The University of Tokyo
2023-2024
University of Toyama
2024
Hokkaido University
2023
Washington State University
1979
We present a measurement of neutrino oscillation parameters with the Super-Kamiokande detector using atmospheric neutrinos from complete pure-water SK I–V (April 1996–July 2020) dataset, including events an expanded fiducial volume. The dataset corresponds to 6511.3 live days and exposure 484.2 kiloton-years. Measurements <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mi...
The first loading of gadolinium (Gd) into Super-Kamiokande in 2020 was successful, and the neutron capture efficiency on Gd reached 50%. To further increase to 75%, 26.1 tons Gd2(SO4)3⋅8H2O additionally loaded (SK) from May 31 July 4, 2022. As amount doubled compared loading, capacity powder dissolving system doubled. We also developed new batches sulfate with even reduced radioactive impurities. In addition, a more efficient screening method devised implemented evaluate these...
Among multi-messenger observations of the next galactic core-collapse supernova, Super-Kamiokande (SK) plays a critical role in detecting emitted supernova neutrinos, determining direction to (SN), and notifying astronomical community these advance optical signal. On 2022, SK has increased gadolinium dissolved its water target (SK-Gd) achieved Gd concentration 0.033%, resulting enhanced neutron detection capability, which turn enables more accurate determination direction. Accordingly,...
We report the first measurement of atmospheric neutrino-oxygen neutral-current quasielastic (NCQE) cross section in gadolinium-loaded Super-Kamiokande (SK) water Cherenkov detector. In June 2020, SK began a new experimental phase, named SK-Gd, by loading 0.011% mass gadolinium into ultrapure The introduction to has effect improving neutron-tagging efficiency. Using 552.2 day dataset from August 2020 2022, we measure NCQE be <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"...
We report a search for time variations of the solar <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mrow><a:mmultiscripts><a:mrow><a:mi mathvariant="normal">B</a:mi></a:mrow><a:mprescripts/><a:none/><a:mrow><a:mn>8</a:mn></a:mrow></a:mmultiscripts></a:mrow></a:math> neutrino flux using 5804 live days Super-Kamiokande data collected between May 31, 1996, and 30, 2018. measured precise each interaction over 22 calendar years to modulations with unprecedented precision....
We present a measurement of neutrino oscillation parameters with the Super-Kamiokande detector using atmospheric neutrinos from complete pure-water SK I-V (April 1996-July 2020) data set, including events an expanded fiducial volume. The set corresponds to 6511.3 live days and exposure 484.2 kiloton-years. Measurements $\Delta m^2_{32}$, $\sin^2\theta_{23}$, $\sin^2 \theta_{13}$, $\delta_{CP}$, preference for mass ordering are presented alone, constraints on \theta_{13}$ reactor experiments....
Abstract Electron heating process in inductively coupled plasmas driven under confronting divergent magnetic fields is investigated by Monte Carlo simulations. &#xD;Enhancement of the electron energy gain due to partial resonance demonstrated adopting driving frequencies 27.12 and 40.68 MHz higher than conventional 13.56 MHz. &#xD;The pressent model reactor arranged so that regions strong near a coil high electric RF antenna overlap. &#xD;In this configuration, with increasing...
Abstract We investigate the partial resonance as one of mechanisms electron heating to sustain inductively coupled plasmas driven under confronting divergent magnetic fields having an confinement function. The dependence on operating conditions is observed. energy gain (EEG), defined a measure for evaluation resonance, was calculated by Monte Carlo method various field strengths and RF antenna positions. It confirmed that observed in resonant region even low electric strong field. As attempt...
We report a search for time variations of the solar $^8$B neutrino flux using 5,804 live days Super-Kamiokande data collected between May 31, 1996, and 30, 2018. measured precise each interaction over 22 calendar years to modulations with unprecedented precision. Periodic are searched in set comprised five-day interval measurements maximum likelihood method. also applied Lomb-Scargle method this compare it previous reports. The only significant modulation found is due elliptic orbit Earth...