A5101406546- Dark Matter and Cosmic Phenomena
- Particle physics theoretical and experimental studies
- Neutrino Physics Research
- Nuclear Physics and Applications
- Radiation Detection and Scintillator Technologies
- Atomic and Subatomic Physics Research
- Astrophysics and Cosmic Phenomena
- Particle Detector Development and Performance
- Radiation Therapy and Dosimetry
- High-Energy Particle Collisions Research
- Nuclear reactor physics and engineering
- Scientific Research and Discoveries
- Experimental and Theoretical Physics Studies
- CCD and CMOS Imaging Sensors
- Electron and X-Ray Spectroscopy Techniques
- Particle Accelerators and Free-Electron Lasers
- Plasmonic and Surface Plasmon Research
- Advanced Fluorescence Microscopy Techniques
- Near-Field Optical Microscopy
- Magnetic confinement fusion research
- Radioactive contamination and transfer
- Advanced Semiconductor Detectors and Materials
- Advanced Electron Microscopy Techniques and Applications
- Atomic and Molecular Physics
- Radioactive Decay and Measurement Techniques
Nagoya University
2012-2024
Obayashi (Japan)
2013-2024
Toho University
2023-2024
University of Bern
2017
Japan Synchrotron Radiation Research Institute
2015
Nagoya University Hospital
2012-2013
We present the case for a dark matter detector with directional sensitivity. This document was developed at 2009 CYGNUS workshop on detection, and contains contributions from theorists experimental groups in field. describe need sensitivity; each experiment presents their project's status; we close feasibility study scaling up to one ton detector, which would cost around $150M.
The OPERA experiment is searching for nu_mu -> nu_tau oscillations in appearance mode i.e. via the direct detection of tau leptons charged current interactions. evidence has been previously reported with three candidate events using a sub-sample data from 2008-2012 runs. We report here fourth event, decaying into hadron, found after adding 2012 run without any muon final state to sample. Given number analysed and low background, are established significance 4.2sigma.
A nuclear emulsion with micronized crystals is required for the tracking detection of submicron ionizing particles, which are one targets dark-matter and other techniques. We found that a new production method, called PVA—gelatin mixing method (PGMM), could effectively control crystal size from 20 nm to 50 nm. two types produced nano imaging tracker ultra-nano tracker. Their composition spatial resolution were measured, results indicate these emulsions detect extremely short tracks.
The OPERA experiment, exposed to the CERN Gran Sasso $ν_μ$ beam, collected data from 2008 2012. Four oscillated $ν_τ$ Charged Current interaction candidates have been detected in appearance mode, which are consistent with $ν_μ\to ν_τ$ oscillations at atmospheric $Δm^2$ within "standard" three-neutrino framework. In this paper, results used derive limits on mixing parameters of a massive sterile neutrino.
Nowadays there is compelling evidence for the existence of dark matter in Universe. A general consensus has been expressed on need a directional sensitive detector to confirm, with complementary approach, candidates found conventional searches and finally extend their sensitivity beyond limit neutrino-induced background. We propose here use based nuclear emulsions measure direction WIMP-induced recoils. The production emulsion films nanometric grains established. Several measurement...
In this study, we are doing R&D for directional dark matter search with nuclear emulsion. First of all, higher resolution emulsion fine silver halide crystals was developed in the production facility at Nagoya university, and confirmed that it can detect expected recoil tracks. The readout submicron tracks required new technology. We expansion technique, could signal by shape analysis optical microscopy. two dimensional angular is 36 degrees original track length range from 150 nm to 200...
In this paper, we summarize a newly developed automatic readout system, composed of microscope with an optics stage, to analyze charged particle tracks less than 1 μm recorded in fine-grained nuclear emulsion. This system's have the high spatial resolution, epi-illumination, and xenon-mercury lamp necessary achieve sufficient contrast brightness for small silver grains up about 40 nm diameter. Methods shape recognition focus point acquisition were that enabled system identify submicron...
A Nano Imaging Tracker (NIT) is a super-fine-grained nuclear emulsion that capable of detecting an ionizing particle with nanometric resolution and recording the track by line silver nanograins various shapes sizes. The tracks need to be read out some microscopic techniques; here we focus on optical response realize readout method beyond diffraction limit. In this paper, super-resolution plasmonic imaging microscopy (SRPIM), which utilizes polarization-dependent due localized surface plasmon...
Several approaches for the direct search of dark matter, in which energy deposited by scattering matter particle is detected, are extensively used to constrain mass and interaction strength these hypothetical particles.Gaining information on income direction interacting would be only way overcome neutrino floor or study properties any found signal.We studying direction-sensitive using a super-high resolution nuclear emulsion, NIT stands Nanoimaging Tracker.NIT consists silver-halide crystals...
Abstract Ambient neutrons are one of the most serious backgrounds for underground experiments searching rare events. The ambient neutron flux in an laboratory at Kamioka Observatory was measured using a $\mathrm{^3He}$ proportional counter with various moderator setups. Since detector response largely depends on spectral shape, energy spectra transported from rock to were estimated by Monte Carlo simulations. ratio thermal total found depend thermalizing efficiency rock. Therefore, count...
Detecting the first electron pairs with nuclear emulsion allows a precise measurement of direction incident gamma-rays as well their polarization. With recent innovations in scanning, analyzing capability is becoming increasingly powerful. Presently, we are developing balloon-borne gamma-ray telescope using emulsion. An overview and status our given.
Analyses of nuclear emulsion detectors that can detect and identify charged particles or radiation as tracks have typically utilized optical microscope systems because the targets lengths from several μm to more than 1000 μm. For recent new submicron length less, current readout are insufficient due their poor resolution. In this study, we developed a system method using an for rough candidate selection hard X-ray at SPring-8 high-precision analysis with resolution better 70 nm Furthermore,...
We have developed a compact fast neutron camera based on stack of nuclear emulsion plates and pinhole collimator. The was installed at J-port Korea superconducting tokamak advanced research National Fusion Research Institute, Republic Korea. Fast images agreed better with calculated ones Monte Carlo simulation using the uniform distribution Deuterium-Deuterium (DD) source in torus 40 cm radius.
In the OPERA experiment, so-called Scan Back method is used to locate neutrino interaction vertices in emulsion target named ECC (Emulsion Cloud Chamber). method, tracks detected most downstream plate ECCs are followed upstream by until it reaches points. order treat a number of interactions recorded OPERA, dedicated systems called Plate Changer has been developed and utilized event location Japan. The details system have described this report. Until end November 2012, 6223 trials performed...
We focused on the difference between photographic sensitivities of nuclear emulsion films by electronic stopping power (ESP) and (NSP) charged particles. The effects high-velocity particles, in which ESP was dominant, low-velocity where both NSP were effective, compared. Low-velocity Kr ions formed internal latent images interaction with NSP. This may be due to formation crystal defects atomic collisions along route these silver halide crystals, such are detected only development. On other...
In order to measure the 2.5 MeV neutrons produced by DD nuclear fusion reactions, we have developed a compact neutron detector based on emulsion. After optimization of development conditions, evaluated response an accelerator-based source. The absolute efficiency at energy was estimated be (4.1±0.2)×10-6 tracks/neutron.
The OPERA experiment has discovered the tau neutrino appearance in CNGS muon beam, agreement with 3 flavour oscillation hypothesis. interaction target, made of Emulsion Cloud Chamber, was particularly efficient reconstruction electromagnetic showers. Moreover, thanks to very high granularity emulsion films, showers induced by electrons can be distinguished from those $\pi^0$s, thus allowing detection charged current interactions electron neutrinos. In this paper results search for events...
Abstract To precisely measure the neutron emissions from a spent fuel assembly of fast breeder reactor, we formed nuclear emulsions based on non-sensitized Oscillation Project with Emulsion tRacking Apparatus (OPERA) film AgBr grain sizes 60, 90, and 160 nm. The efficiency for 252Cf detection new emulsion was calculated to be 0.7 × 10−4, which corresponded an energy range 0.3 2 MeV consistent preliminary estimate experimental results. sensitivity also experimentally estimated by irradiating...