Current status and future prospect of RPL glass dosimeter

Radiation Measurements

Published On 2020/8/1

Silver-activated phosphate glass has long been used as passive-type solid state dosimeter for both individual and environmental dose monitoring. The principle is classified as radio-photoluminescence (RPL) whose mechanism is different from TSL and OSL. The RPL dosimeter has excellent characteristics such as stable sensitivity, negligible fading and reliable repeatability in radiation dose measurement. In Japan it is named “Glass Badge” and has come into wide use in individual dose monitoring services. In order to contribute to restoration of the contaminated area in Fukushima new-type glass dosimeters have been developed and the fruits of this work have led to various applications.

Journal

Radiation Measurements

Published On

2020/8/1

Volume

136

Page

106363

Authors

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Position

H-Index(all)

44

H-Index(since 2020)

19

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

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0

Research Interests

Odor sensor

Dosimeter

Thin films

University Profile Page

Other Articles from authors

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Journal of Alloys and Compounds

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Sensors and Materials

Radio-photoluminescence Properties of Eu-doped CaBPO5

Eu-doped CaBPO5 was synthesized by the solid-state reaction route, and then its radiophotoluminescence properties were studied. On the basis of steady-state and time-resolved photoluminescence (PL) studies, it was confirmed that Eu2+ is formed by X-ray irradiation due to the valence change of the Eu ion (Eu3+→ Eu2+). In addition, for dosimetric applications, it was demonstrated that the PL intensity of Eu2+ is proportional to the accumulated radiation dose, is stable after irradiation, and can be reversed by heat treatment at 500℃ for 100 s.

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Japanese Journal of Applied Physics

Radiophotoluminescence properties of Eu-doped Li2SrSiO4 for radiation detectors

To search for new radiophotoluminescence (RPL) materials, Eu-doped Li 2 SrSiO 4 was synthesized by the solid-state reaction and then studied its RPL properties for radiation detector applications. All the samples were identified to be Li 2 SrSiO 4 by X-ray diffraction. The as-prepared sample shows photoluminescence (PL) due to Eu 3+ while an additional PL band appears due to a formation of Eu 2+ after X-ray irradiation. This indicates that the Eu-doped Li 2 SrSiO 4 has RPL properties. The sensitivity of RPL (or PL intensity of Eu 2+) to X-ray dose is the highest when the Eu concentration is 0.1%, and the dynamic range is 5–10 000 mGy. In addition, the generated Eu 2+ is so stable that only 5% of the signal degrades over 20 min after irradiation. The RPL signal notably decreases to about 30% of the initial value by heating at 500 C for 100 s, and it is reproducible multiple times even after the heat treatment.

2023/12/20

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Materials Research Bulletin

X-ray induced reduction of Sm3+ into Sm2+ in Li2CaSiO4 and its potential for radiation measurement applications

In Sm3+-doped Li2CaSiO4, the Sm3+ ion is reduced to the Sm2+ state by X-ray irradiation. The valence change was confirmed by the difference in their photoluminescence spectra, measured before and after irradiation. Only luminescence peaks due to the 4f-4f transitions of Sm3+ are observed before the irradiation while an additional luminescence band is observed at 900 nm due to the 5d-4f transition of Sm2+. The reaction is that a fraction of X-ray generated electrons is captured by Sm3+ ions, which convert to the Sm2+ state. The generated Sm2+ state is fairly stable while it is effectively reversed back to the Sm3+ state by a heat treatment at an elevated temperature. A numerical approximation revealed the activation energy to be 0.40 and 0.52 eV. Even after the heat-treatment, the reduction of Sm3+ to Sm2+ is reproducible multiple times, which shows good potential for using radiation measurement applications.

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Journal of Materials Science: Materials in Electronics

Radio-photoluminescence properties of Eu-doped SrAl2O4 ceramics and thermally assisted charge transfer process

Radio-photoluminescence (RPL) properties of Eu-doped SrAl2O4 are studied focusing on the generation of a luminescent center by ionizing radiation of X-ray and its extinction by a thermally assisted charge transfer. The single phases of SrAl2O4 doped with Eu at concentrations of 0.05–1.0% are synthesized via solid-state reactions, as confirmed by X-ray diffractions analyses. They show photoluminescence (PL) due to both Eu3+ and Eu2+, and the PL intensity due to Eu3+ decreases after X-ray irradiation while the one due to Eu2+ notably increases. This indicates that Eu2+ as a luminescence center is generated as RPL through reduction from Eu3+ to Eu2+ by ionizing radiation of X-ray. Particularly, the 0.1% Eu-doped sample shows the highest sensitivity to X-ray dose, and the lowest detection limit is estimated to be 0.3 Gy with the present reader system. The RPL signal is reasonably stable, and it depends on …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Recent advances in radiophotoluminescence materials for luminescence dosimetry

Radiophotoluminescence (RPL) is a phenomenon in which a luminescence centre is formed in a medium upon interaction with ionizing radiation. The RPL is observed by a conventional photoluminescence (PL) technique, and the PL intensity is proportional to the dose. With the latter feature, the RPL has found successful applications in personnel and environmental dosimetry. However, the conventional materials considered for radiation measurements may be limited to Ag-doped phosphate glass, LiF, and Al 2 O 3: C, Mg. The recent research works, however, have found a number of additional RPL materials for luminescence dosimetry. The aim of the present paper is to review the series of newly reported RPL materials and potential applications in dosimetry.

2022/11/22

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Optically stimulated luminescence dosimeters: principles, phosphors and applications

This review paper discusses the basics of the optically stimulated luminescence (OSL) phenomenon, phosphors for OSL, functional design of OSL phosphors, and application areas of the OSL phenomenon, such as radiation dose monitoring for individual and environmental, computed radiography for medical and dental diagnosis, dating, security, archaeological dating, and autoradiography for drug discovery. Finally, the future prospects of the OSL phenomenon as passive-type dosimeters are mentioned.

2022/11/21

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

IEEJ Transactions on Sensors and Micromachines

Proposal of Temperature Behavior Analysis and Temperature Dependence Reduction of Stem Water Content Variation Sensor

Proposal of Temperature Behavior Analysis and Temperature Dependence Reduction of Stem Water Content Variation Sensor - NASA/ADS Now on home page ads icon ads Enable full ADS view NASA/ADS Proposal of Temperature Behavior Analysis and Temperature Dependence Reduction of Stem Water Content Variation Sensor Ueno, Chiemi ; Hirasawa, Kazuki ; Takei, Yoshinori ; Nanto, Hidehito Abstract Publication: IEEJ Transactions on Sensors and Micromachines Pub Date: June 2022 DOI: 10.1541/ieejsmas.142.117 Bibcode: 2022IJTSM.142..117U No Sources Found © The SAO/NASA Astrophysics Data System adshelp[at]cfa.harvard.edu The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement NNX16AC86A NASA logo Smithsonian logo Resources About ADS ADS Help What's New Careers@ADS Social @adsabs ADS Blog Project Switch to full ADS Is …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Sensors and Materials

Radiophotoluminescence Imaging Reader for Passive Dosimetry

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Japanese Journal of Applied Physics

RPL properties of samarium-doped CaSO4

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Phosphors for Radiation Detectors

radiophotoluminescence (RPL)

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Phosphors for Radiation Detectors

Optically‐Stimulated Luminescent Dosimeters

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Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Journal of The Institute of Electrical Engineers of Japan

What Did the Great Persons Who Changed the World Think and Say?

What Did the Great Persons Who Changed the World Think and Say? - NASA/ADS Now on home page ads icon ads Enable full ADS view NASA/ADS What Did the Great Persons Who Changed the World Think and Say? Nanto, Hidehito Abstract Publication: Journal of The Institute of Electrical Engineers of Japan Pub Date: January 2022 DOI: 10.1541/ieejjournal.142.34 Bibcode: 2022JIEEJ.142...34N full text sources Publisher | © The SAO/NASA Astrophysics Data System adshelp[at]cfa.harvard.edu The ADS is operated by the Smithsonian Astrophysical Observatory under NASA Cooperative Agreement NNX16AC86A NASA logo Smithsonian logo Resources About ADS ADS Help What's New Careers@ADS Social @adsabs ADS Blog Project Switch to full ADS Is ADS down? (or is it just me...) Smithsonian Institution Smithsonian Privacy Notice Smithsonian Terms of Use Smithsonian Astrophysical Observatory …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Physical Review Research

Catalog of gamma-ray glows during four winter seasons in Japan

In 2015, the Gamma-Ray Observation of Winter Thunderstorms (GROWTH) collaboration launched a mapping observation campaign for high-energy atmospheric phenomena related to thunderstorms and lightning discharges. This campaign has developed a detection network of gamma rays with up to 10 radiation monitors installed in the cities of Kanazawa and Komatsu, Ishikawa Prefecture, Japan, where low-charge-center winter thunderstorms frequently occur. During four winter seasons from October 2016 to April 2020, a total of 70 gamma-ray glows, ie, minute-lasting bursts of gamma rays originating from thunderclouds, were detected. Their average duration is 58.9 s. Among the detected events, 77% were observed at night. The gamma-ray glows can be classified into temporally symmetric, temporally asymmetric, and lightning-terminated types based on their count-rate histories. An averaged energy …

2021/11/15

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Materials Letters

Radiation-induced reduction of Eu3+ doped in SrAl2O4

In this letter, we report radio-photoluminescence (RPL) properties of Eu-doped SrAl2O4. The RPL is a phenomenon in which a new luminescence center is generated by ionizing radiation. The material was synthesized via the solid-state reaction. The synthesized sample shows photoluminescence (PL) due to the 4f-4f transition of Eu3+ and the 4f65d1 → 4f7 transition of Eu2+. After X-ray irradiation, the former emission intensity decreases while the latter one increases, and the extent of the change depends on the radiation dose. The change in the RPL is attributed to a reduction of Eu3+ by trapping an X-ray generated electron (Eu3+→Eu2+). In addition, a heat-treatment effectively reverses the above reaction by detrapping an electron from the Eu2+ center.

2021/11/15

Article Details
Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Sensors & Materials

TSL/OSL/RPL Automated and Integrated Measurement System (TORAIMS).

Thermally stimulated luminescence (TSL), optically stimulated luminescence (OSL), and radio-photoluminescence (RPL) are radiation-induced luminescence phenomena, and they are widely used for radiation dosimetry today. Despite their successful applications, the R&D of conventional and new phosphor materials is still actively performed in a wide range of research fields from basic science to application. Although these phenomena are considered to be different, they share common physical processes such as the generation, trapping, and transfer of electronic charges. In order to have a deeper look into these phenomena, it is important to comprehensively characterize those of a single material. For this, we have constructed a prototype TSL/OSL/RPL automated and integrated measurement system (TORAIMS), and then the system performance has been studied. The system offers automated and integrated …

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Radioprotection

Characterization of optically-stimulated luminescence properties by NaCl: Eu2+ crystal and the thermal response

[en] Landauer optically stimulated luminescence (OSL) technology nanoDot dosimeters (OSLDs) are characterized for use in mammography screening at various tube voltages, mAs values and target/filter combinations. The average glandular dose (AGD) for a 50-mm breast, based on the representative compressed breast thickness of a 45-mm polymethyl methacrylate (PMMA) phantom, is assessed using OSLDs with different beam conditions. Further, the linearity of the OSLD response is measured and angular dependence tests are performed for various tube potentials, mAs and target/filter combinations. The breast-absorbed doses are measured at various depths for a 32-kVp X-ray beam at 100 mAs, with a Mo/Rh target/filter combination. The measured incident air kerma values at different lateral positions exhibit a maximum deviation of 6%, and the average relative response of the OSLDs at the reference point (center) with respect to various lateral positions is found to be 1.001±0.09%. The calculated AGD values are in the 1.3±0.1-3.5±0.2 mGy range, depending on the tube potential, tube loading and target/filter combinations. An exposure setup featuring the auto-exposure control (AEC) mode, 28 kVp, 73.8 mAs, and a Mo/Rh target/filter combination may be preferred for mammography screening for a compressed breast thickness of 45 mm.(authors)

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

電気学会研究会資料

Transient response analysis and feature extraction of semiconductor gas sensors for an application to machine olfaction

瀬戸就一 他: 半導体式ガスセンサの過渡応答出力の解析, 電気学会論文誌 E センサマイクロマシン準部門誌 Vol. 125 No. 3, p. 129-134 (2005)

Hidehito Nanto

Hidehito Nanto

Kanazawa Institute of Technology

Radiation Measurements

Physical and dosimetric characteristics of radiophotoluminescent glass from two-photon excitation microscopy

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Radiation Measurements

Characterisation of a customised 4-chip Timepix3 module for charged-particle tracking

Ion-beam radiotherapy is a growing cancer treatment modality because it offers a superior dose distribution in the patient compared with conventional radiotherapy using X-rays. Thanks to their versatility, application-specific integrated circuits (ASIC) increasingly gain interest for research into ion imaging and ion-beam characterisation. Timepix3 is a hybrid semiconductor pixel detector, which offers nanosecond time binning as well as dead-time-free and noise-free data-driven readout at a pixel pitch of 55 µm × 55 µm. In this work, a novel 4-chip Timepix3 mini-tracker (quad module) was characterised in a therapeutic proton beam. The quad module has two detection layers equipped with two Timepix3 chips each, which are stacked like a particle telescope at a distance of 20.3 mm. In a detection layer, two Timepix3 chips share the same sensitive silicon sensor. The surface area of the silicon sensor is approximately …

Osman Vefa Gul

Osman Vefa Gul

Selçuk Üniversitesi

Radiation Measurements

Investigation of skin dose of post-mastectomy radiation therapy for the halcyon and tomotherapy treatment machine: Comparison of calculation and in vivo measurements

In treatments such as post-mastectomy radiation therapy (PMRT) for breast cancer patients, skin doses are of great importance in terms of tumor control and side effects. This dosimetric study aimed to measure the skin dose on the chest wall surface for post-mastectomy radiotherapy with Tomotherapy and Halcyon devices using thermoluminescence dosimetry (TLD) and to evaluate the accuracy of the skin dose calculated by treatment planning systems (TPS). Computed tomography (CT) images of the Alderson Rando phantom were obtained. Treatment plans were created with Tomotherapy and Halycon devices for a total of 50 Gy with a fraction dose of 2 Gy to the target volume. The left chest wall was divided into 9 regions for detailed surface dose assessment. 88 dose measurement points were determined on the left chest wall. The phantom was irradiated separately in Halycon and Tomotherapy devices. In …

Geoff Duller

Geoff Duller

Aberystwyth University

Radiation Measurements

Chasing snails: Automating the processing of EMCCD images of luminescence from opercula

Opercula of the gastropod Bithynia tentaculata are composed of calcite, and are typically 2–4 mm in length. They emit a thermoluminescence (TL) signal that can be used for dose reconstruction, and spatially resolved TL data from them can be obtained using an electron multiplying charge coupled device (EMCCD). However, when multiple measurements are made of the same sample with imaging detectors such as the EMCCD, registering the different images is crucial so that when regions of interest (ROI) are defined they consistently relate to the same part of the specimen. Previous work on opercula has undertaken this registration by hand, but this is prohibitively time consuming and is also potentially prone to human error. An automated registration process is described, and its use is illustrated using a dose recovery experiment. Without registration more than half of the regions of interest defined across the …

Diyun Shu

Diyun Shu

Nanjing University of Aeronautics and Astronautics

Radiation Measurements

Advancing 2D Reaction Rate Measurements in BNCT: Validation of the Indirect Neutron Radiography Method

The precise characterization of neutron beams is a cornerstone of Boron Neutron Capture Therapy (BNCT). While Instrumental Neutron Activation Analysis (INAA) is the standard technique for neutron flux measurement, it is limited in its ability to capture two-dimensional (2D) reaction rate distributions. This study aims to validate the Indirect Neutron Radiography (INR) method for 2D reaction rate quantification, addressing critical variables such as temperature sensitivity and signal fading. We engineered an optimized INR platform comprising an Imaging Plate (IP), readout device, activation detectors (copper foils), and real-time temperature monitoring. Comprehensive experiments were conducted to investigate the impact of ambient temperature and fading time on IP signal reliability. A robust calibration curve was formulated, linking IP signals to dose deposition metrics, thereby enabling precise reaction rate …

Christoph Schmidt

Christoph Schmidt

Université de Lausanne

Radiation Measurements

Testing emergency radiation doses by metastable TL peaks in quartz− preliminary investigations

In the case of nuclear or radiological emergencies, rapid examination of individuals from affected areas is necessary. The limited capacity of existing laboratories and dosimetric methods requires narrowing down, using short−term emergency dosimetry, the areas in which people should be examined first. Quartz, the abundant mineral widely used in dating and luminescence retrospective dosimetry, is an obvious candidate for a dosimeter in such cases. Until now, most dose reconstruction studies using quartz from buildings, structures and ceramics have used high−temperature thermoluminescence (TL) or optically stimulated luminescence (OSL) from relatively stable trapping systems. The separation of residual signals from long−term exposure to natural radioactivity and time−consuming measurement sequences is an issue with the high−temperature methods. While less explored for dose reconstruction, the TL …

Hiroshi Yasuda

Hiroshi Yasuda

Hiroshima University

Radiation Measurements

Preliminary analyses of radiophotoluminescence centers in a recently developed Ag-doped alkali-phosphate glass (SAPANS)

The mechanism behind radiophotoluminescence (RPL) emission in Ag-doped alkali-phosphate glass remains unclear. To contribute to resolving this issue, the authors measured and analyzed the temporal change of electron spin/paramagnetic resonance (ESR) spectrum of a recently developed, weather-resistant RPL glass, named “SAPANS,” after irradiation with X-rays. As a result, a continuous gradual increase in Ag2+-derived signals was observed even at four weeks post-irradiation, which corresponded well with the time build-up pattern of the RPL of SAPANS. In contrast, the signals derived from phosphorous-oxygen-hole centers (POHC) rapidly decreased over a few days. The peaks of Ag0 and Ag2+ were not successfully separated from the ESR spectra because of the possible overlap of unidentified peaks, which implies a complex mechanism of RPL-center formation in Ag-doped alkali-phosphate glass …