A5014877775- Astrophysics and Cosmic Phenomena
- Particle Detector Development and Performance
- Neutrino Physics Research
- Particle physics theoretical and experimental studies
- Dark Matter and Cosmic Phenomena
- Radiation Detection and Scintillator Technologies
- Radio Astronomy Observations and Technology
- Muon and positron interactions and applications
- Planetary Science and Exploration
- Seismology and Earthquake Studies
- earthquake and tectonic studies
- Underwater Vehicles and Communication Systems
- Astro and Planetary Science
- Methane Hydrates and Related Phenomena
- Geological and Geochemical Analysis
- Indoor and Outdoor Localization Technologies
- Atomic and Subatomic Physics Research
- Cryospheric studies and observations
- Earthquake Detection and Analysis
- Spacecraft and Cryogenic Technologies
- Nuclear Physics and Applications
- Network Time Synchronization Technologies
- Landslides and related hazards
- Nuclear physics research studies
- Seismic Waves and Analysis
The University of Tokyo
2016-2025
Earthquake Engineering Research Institute
2012-2025
Association for the Development of Earthquake Prediction
2010-2024
Institute for Cosmic Ray Research
2015-2022
Kavli Institute for the Physics and Mathematics of the Universe
2018-2022
University of Alaska Anchorage
2021
Providence College
2021
Clark Atlanta University
2021
The University of Texas at Arlington
2021
Michigan State University
2021
An analysis of solar neutrino data from the fourth phase Super-Kamiokande (SK-IV) October 2008 to May 2018 is performed and results are presented. The observation time dataset SK-IV corresponds 2970 days total live for all four phases 5805 days. For more precise measurements, several improvements applied in this analysis: lowering acquisition threshold 2015, further reduction spallation background using neutron clustering events, energy reconstruction considering variation PMT gain. observed...
Radiographic imaging of magma dynamics in a volcanic conduit provides detailed information about ascent and descent magma, the flow rate, diameter inflation deflation due to volatile expansion release. Here we report first radiographic observation along utilizing atmospheric (cosmic ray) muons (muography) with dynamic imaging. Time sequential images show that top column ascends right beneath crater floor through which eruption was observed. In addition visualization this inflation, sequence...
Are there more than three types of neutrinos in nature ? Some experiments show that should exist at least one type, called sterile neutrinos. Using atmospheric neutrino data from the Super-Kamiokande experiment, authors find new limits on oscillations.
Muography is a novel method to highly resolve the internal structure of active volcanoes by taking advantage cosmic muon's strong penetration power. In this paper, we present first high-definition image in vicinity craters an erupting volcano called Sakurajima, Kyushu, Japan. The muography observation system based on technique multi-wire proportional chamber (mMOS) has been operated reliably during data period 157 days. mMOS measured precisely flux muons up thickness 5,000...
Abstract Muography consists in observing the differential absorption of muons – elementary particles produced through cosmic-ray interactions Earth atmosphere going volcano and can attain a spatial resolution tens meters. We present here first experiment nuclear emulsion muography at Stromboli volcano. Muons have been recorded during period five months by detector 0.96 m 2 area. The films were prepared Gran Sasso underground laboratory analyzed Napoli, Salerno Tokyo scanning laboratories....
Muon radiography can provide essentially a cross section through the object parallel to plane of detector, on which average density along all muon paths is projected, somewhat like X‐ray radiography. Very recently use emulsion films has given us clue for visualization interior volcanoes. To image larger volcano in shorter time, we need detector collect more events. However, time required imaging will be proportional detection area. In order overcome this problem, developed portable assembly...
We developed a radiographic technique to image subsurface conduit shape using cosmic‐ray muons. The test measurement was performed in Showa‐Shinzan lava dome located Hokkaido, Japan as an example. A muon detector with area of 6000 cm 2 set up at the foot dome. Muon tracks recorded nuclear emulsion films were analyzed determine level energy absorption along different ray paths through beneath typical angular resolution 10 mrad corresponds spatial m distance 1 km, which is difficult be...
Cosmic ray muon radiography can measure the density distribution within a volcano. Unidirectional shows precise cross‐sectional view of conduit and magma body through volcano parallel to plane detector. However, it only resolves average along individual paths. Precise size shape underground structure, such as or body, provide clear pervasive information on understanding dynamics volcanic eruption. Here we show highly resolved three‐dimensional tomographic image an active Asama in Japan....
Here, we report the first redox-active chiral dopant FcD, which electrically alters its helical twisting power (HTP) for a cholesteric liquid crystalline (LC) medium and quickly changes reflection color. FcD is composed of an axially binaphthyl unit in conjunction with ferrocene unit. A LC phase 4′-pentyloxy-4-cyanobiphenyl, doped (3.0 mol %), developed blue When nitrosyl tetrafluoroborate, one-electron oxidant, was added to this phase, oxidized decrease original HTP value by 13%, so that...
A visual detection and monitoring of volcanic eruptions is the most essential information. In February 2, 2009, Asama volcano, Japan erupted a large amount ash was ejected from vent. We have observed activity at since October 12, 2008. For eruption we used cosmic‐ray muon radiography (muography), new volcano system recently developed by Tanaka et al. (2009). measured quantitative mass loss inside crater during event although no changes were found below crater. The value 30,780 tons...
Muon Radiography allows to map the density of a volcanic cone. It is based on measurement attenuation flux muons present in cosmic radiation ground. The MU-RAY project has developed an innovative detector designed for muon radiography. main features are low electric power consumption, robustness and transportability, good spatial resolution time flight measurement. A 1 m2 prototype been constructed. collected data at Mt. Vesuvius approximately month spring 2013. second campaign performed Puy...
The modulation speed of light-emitting diodes (LEDs) must be increased to improve the speed, increase bandwidth, and miniaturize hardware visible light communication (VLC) systems. LED is limited by remaining carriers that remain in depletion capacitance. In this paper, we evaluate optical transmission rate for an driver first time sweeping out a GaN-based VLC system. fabricated using discrete GaAs FETs passive elements on board. An experiment performed. experimental results demonstrate...
Cosmic-ray muon radiography has the potential to reveal density structure of gigantic objects. It utilizes strong penetration ability high-energy muons. By measuring number muons that travel through a target object, average can be calculated along path. Since in straight paths matter, specially designed detectors generate maps with higher spatial resolution than those obtained conventional geophysical methods. However, this technique few notable limitations it only applied near-surface...
An emerging elementary particle imaging technique called muography has increasingly been used to resolve the internal structures of volcanoes with a spatial resolution less than 100 m. However, land-based requires several days at least acquire satisfactory image contrast and thus, it not practical tool diagnose erupting volcano in real time manner. To address this issue, airborne was implemented for first time, targeting Heisei-Shinzan lava dome Unzen volcano, Japan. Obtained 2.5 hours,...
Abstract Sakurajima Muography Observatory captured the formation of a volcanic plug beneath Showa crater with spatial resolution ∼60 m in accordance end eruption episode and reactivation Minamidake crater. The increase average density was observed above 3 σ standard deviation for both floor crater, respectively, being interpreted as ejecta deposition laterally extended within few hundreds meters.
Abstract While satellite-based global navigation systems have become essential tools in our daily lives, their effectiveness is often hampered by the fact that signals cannot be accessed underground, indoor, or underwater environments. Recently, a novel system has been invented to address this issue utilizing characteristics of ubiquitous and highly penetrative cosmic-ray muons. This technique, muometric navigation, does not require active signal generation enables positioning aforementioned...
By using true random number (TRN) generators, encoding with the highest security can be realized. However, a completely secure strategy to transfer these TRNs has not yet been devised. Quantum key distribution (QKD) attempted establish methodology of this kind; however, several quantum cracking strategies have predicted and experimentally demonstrated. In work, COSMOCAT was invented as solution for next-generation ultrahigh near-field communications. With COSMOCAT, are generated from...
Navigation in indoor and underground environments has been extensively studied to realize automation of home, hospital, office, factory mining services, various techniques have proposed for its implementation. By utilizing the relativistic penetrative nature cosmic-ray muons, a completely new wireless navigation technique called muometric system (MuWNS) was developed. This paper shows results world's first physical demonstration MuWNS used on basement floor inside building navigate (a...
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,...