Japan Atomic Energy Research Institute

Japan Atomic Energy Agency

Chichibu Fuji Co., Ltd.

Sumitomo Heavy Industries, Ltd.

Other

National Institute of Advanced Industrial Science and Technology

Horshin Electronics Co., Ltd.

Agency of Japan Atomic Energy Research Institute

Hoshin Electronics Co., Ltd.

Masaki Katagiri

Tatsuya Nakamura

Noriaki Tsutsui

Masataka Ohkubo

Masumi Ebine

Atsushi Birumachi

Yutaka Yoribayashi

Masahito Matsubayashi

Toshio Uchida

Yoshito Taguchi

Yasunobu Noguchi

Akira Ohzu

Ikuo Kanno

Hirofumi Ooguri

Atsushi Sakaue

Osamu Sugiura

Yoshii Kobayashi

To provide Zinc Sulfide activated with Silver (ZnS:Ag) based fluorescent material for detecting particle beams, having lower gamma-ray sensitivity and providing lower afterglow, and being specialized for the purpose of detecting particle beams, and its manufacturing method. Zinc Sulfide activated with Silver (ZnS:Ag) based fluorescent material for detecting particle beams emits fluorescence with wavelengths from 320 nm to 580 nm in response to alpha-ray irradiation, and has a fluorescence spectrum with a peak wavelength from 395 nm to 410 nm.

ZnS fluorescent material and manufacturing method thereof

A neutron detector with a unique neutron detecting element is disclosed. The neutron detecting element has an inner cylindrical neutron scintillator where a neutron detection body including a ZnS phosphor, and a neutron converter material which containsLi orB is arranged outside of the cylindrical substrate; a scintillator fluorescence detection body made by placing coiled wavelength shift fibers where two wavelength shift fibers are wound in parallel along the cylindrical substrate on said inner cylindrical neutron scintillator; and an outer cylindrical neutron scintillator where a neutron detection body is arranged inside of the cylindrical substrate, the outer cylindrical neutron scintillator being arranged on the scintillator fluorescence detection body. The fluorescence signals converted into pulse signals by two optical detectors are led to a coincidence circuit, and when two fluorescence signals are measured simultaneously during the predetermined period of time, a neutron signal is output.

Neutron detector

In a lattice-like pixel structure in which reflecting plates that reflect a fluorescent light from a fluorescent material-based neutron detecting sheet are arranged along vertical and horizontal axes at a regular interval, a lattice-like fluorescent light detecting member is provided, in which grooves may be formed at an upper half position of the vertical axis direction reflecting plate and at a center position in a vertical axis interval for accommodating a wavelength shifting fiber for vertical axis detection and at a lower half position of the horizontal axis direction reflecting plate and at a center position in a horizontal axis interval for accommodating a wavelength shifting fiber for horizontal axis detection; and a fluorescent material-based neutron detecting sheet is arranged only at a front surface or at both of a front surface and a back surface of the lattice-like fluorescent light detecting member.

Pixel-type two-dimensional image detector

A neutron detector withoutHe gas, provided with a translucent type plate neutron scintillator having the structure capable to emit fluorescence from double-sides; the neutron scintillator is composed of ZnS fluorescent substance and a neutron converter which containsLi orB, and arranged at an angle of 45 degrees from the neutrons which are incident in parallel all together, inside of a cylindrical detector housing with the circular or square section where the specular reflector with the reflectance of 90% or more is arranged internally, and the fluorescence emitted when the neutron enters the scintillator is detected by two photo multipliers arranged on both sides, and signals output from these two photo multipliers are processed to be taken out as a neutron signal.

Neutron detector and neutron image detector with scintillator

A neutron image detection method is disclosed, which collects a fluorescent light generated by a neutron incident at a designated position interval in one-dimensional geometry and determines an incident position of the neutron by detecting the collected fluorescent light, in which the fluorescent light is detected by a photon counting method; a pulse signal generated by an individual output photon is extracted on the basis of a clock signal generated with the same time interval as the time width of the pulse signal generated by a single photon; a count-value distribution is obtained in terms of incident position as variable determined by a single neutron incident by counting the pulse signal output; and a neutron incident position is determined by calculating a median point on the basis of the obtained count-value distribution.

Neutron image detecting method and neutron image detector using its method

The characteristics of the phosphor ZnS:Ag,Cl which has a considerably high fluorescence yield in response to incident particles thus allowing for their easy detection are used as such and combined with the finding that the fluorescence components in the range of shorter wavelengths are short-lived, which led to an improvement of counting characteristics, hence allowing for high-rate measurements of particles. When B370 was used as an optical filter to pick up fluorescence components shorter than 450 nm, the decay time of short-lived fluorescence components could be reduced from 370 ns to 200 ns.

Particle detector and neutron detector that use zinc sulfide phosphors

A radiation or neutron detector wherein lateral side light detecting optical fibers prepared from clear optical fibers that are scraped on a lateral side to permit side incidence of fluorescence are used to detect the fluorescence from a phosphor or a scintillator such that the background to gamma-rays is reduced. If desired, the optical fibers may be bent at 90 degrees and guided to a photomultiplier tube in order to reduce the size of the detector. Fabrication and maintenance of the detector can be facilitated by adopting such a design that a detecting block comprising a detection medium and lateral side light detecting optical fibers is separated from a readout block comprising clear optical fibers.

Radiation or neutron detector using fiber optics

A neutron detecting scintillator that has a very short decay time, that can capture neutrons in high efficiency and that is composed of light elements comprises the LiBOsingle crystal or theLi andB orB enrichedLiBOorLiBOsingle crystal, in whichLi andB orB have large neutron capture cross sections and fluorescence that is emitted from an ionizing radiation generated through their neutron capture reaction has a short-lived component not longer than 10 ns.

Scintillators for neutron detection and neutron detectors using the same

In the improved neutron image detector, MgBenriched in a constituent elementB of wide energy gap is used as a neutron detection plate, which is provided at the center and the four corners with a phonon sensor comprising an insulation layer overlaid with MgBenriched inB of narrow energy gap in order to detect phonons resulting from the generation of &#x3b1;-rays which occurs in the detection plate upon incidence of neutrons, and sensor's signal intensity and signal propagation time are used to detect the incident position of neutrons.

Methods for detecting photons, radiations or neutrons using superconductors and methods for obtaining two-dimensional images thereof

A high-purity InSb single crystal not artificially doped with impurities is used as a radiation detecting medium. In order to obtain diode characteristics, a Au.Pd alloy is used to form a surface barrier layer. At 4.2 K, the device resistance of the thus fabricated solid-state radiation detector was as large as 1.4 k&#x3a9; and the rise time of output signals from a charge-sensitive preamplifier was as short as 0.4 &#x3bc;s, indicating reduced trapping of electrons or positive holes. The detector was also capable of measuring &#x3b1;-ray spectra over the temperature range from 2 K to 50 K.

Solid-state radiation detector using a single crystal of compound semiconductor InSb

Apparatus and method for radiation measurement suitable for use within and outside nuclear reactor or accelerator facilities when there is a need to perform real-time monitoring of radiation intensity over a wide dynamic range at many and broadly distributed sites of measurement. The apparatus and method are based on two principles: constant radiation monitoring and integrating measured radiation with a stimulable phosphor.

Apparatus and method for detecting radiation that uses a stimulate phosphor

ALi doped glass scintillator sheet with grooves cut at given spacings in horizontal and vertical directions. Bundles of wavelength shifting fibers placed in the vertical grooves and fluorescence reflector buried in the horizontal grooves make a group of detection pixels. Neutron detecting media are provided on the top surface and bundles of wavelength shifting fibers are arranged horizontally on the bottom surface of the scintillator. Fluorescence generated by stimulation with the neutrons entering the detection pixels and with the neutrons incident on the neutron detecting media are detected by the wavelength shifting fibers. The detected fluorescence is converted to electric signals with a multi-channel photomultiplier tube, with pulse signals for simultaneous counting generated from a retriggerable, constant time-duration pulse generator and recorded as time-series data by parallel interfaces. The recorded data are analyzed by the simultaneous counting method to produce a two-dimensional neutron image.

Growing community of inventors

Ibaraki-ken, Japan

Masaki Katagiri