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All-inorganic halide crystal CsPbBr3 has gained significant attention due to its outstanding high-energy ray resolution capability and excellent environmental adaptability. However, due to the presence of structural phase transitions and thermal stresses, stress is prone to arise during the growth process of large-sized CsPbBr3 crystals, leading to defects such as cracks on the crystal surface, subgrain boundaries and twin crystals. These defects have severely impact on the performance of CsPbBr3 crystals. Currently, large-sized high-quality CsPbBr3 still can’ t be mass-produced through effective means, restricting its further application. Hence, conducting research on the growth and performance of large-sized CsPbBr3 crystals holds great theoretical significance and practical value. This paper briefly summarizes the fundamental properties, crystal preparation methods and research progress of CsPbBr3 crystals, mainly discussing the influencing factors of the vertical Bridgman growth method, and proposing novel optimization ideas for the growth of high-quality CsPbBr3 crystals. [ABSTRACT FROM AUTHOR]

A Cu+ doped high alumina borosilicate glass with long persistent luminescence (LPL) was prepared by reduction melting and radiation induction based on glass defect engineering. The maximum time of the persistent luminescence can arrive 16 h. Spectral and EPR measurements indicate that two kinds of oxygen defects can be induced by X-ray radiation. One defect was eliminated after UV irradiation, and the other can synergistically participate in the LPL process of glass with reduction induced oxygen deficiency centers(ODCs). In addition, there is a highly linear relationship between the initial LPL intensity of the glass and the radiation dose; which implies the glass can be used as a radiation detection material. The internal mechanism of the linear relationship and LPL was discussed. [ABSTRACT FROM AUTHOR]

Radiation detection uses semiconductor materials to convert high-energy photons into charge (direct detection) or low-energy photons (indirect detection), and it has a wide range of applications in nuclear physics, medical imaging, astronomical detection, homeland security, and other fields. Metal halide perovskites have the advantages of high frequency number, high carrier mobility, high defect tolerance, low defect density, adjustable band gap, and fast light response, and they have wide application prospects in the field of radiation detection. However, the research is still in its infancy stage, and it is far from meeting the requirements of industrial application. This paper focuses on the advantages of metal halide perovskite single-crystal materials in both semiconductors-based direct conversion detection and scintillator-based indirect detection as well as the latest progress in this promising field. This paper not only introduces the latest application of lead halide perovskite monocrystalline materials in high-energy electromagnetic radiation detection (X-ray and γ-rays), but it also introduces the latest development of α-particle/β-particle/neutron detection. Finally, this paper points out the challenges and future prospects of metal halide perovskite single-crystal materials in radiation detection. [ABSTRACT FROM AUTHOR]

Electron beam (EB) technology typically consists of high‐energy electron streams produced by a linear accelerator. Although promising, the use of EB irradiation as a technique to delay ripening and prevent spoilage in tomatoes has not been extensively investigated. In this study, the effectiveness of EB irradiation in prolonging the shelf life of tomatoes postharvest was investigated. The results indicated that EB irradiation successfully reduced microbial contamination and decay, preserved key quality attributes (such as total soluble solids, titratable acidity, pH, and firmness), and significantly minimized weight loss. Notably, the treatment delayed the biosynthesis of lycopene, a key indicator of ripening, without adversely affecting phenolic content and antioxidant activity, which remained consistent regardless of irradiation. Additionally, different methods for detecting irradiation were evaluated. Thermoluminescence analysis proved to be the most dependable technique, especially for doses exceeding 600 Gy, due to its high sensitivity and specificity. In contrast, photostimulated luminescence and electron spin resonance analyses showed limitations in accurately identifying the irradiation status of foods with high moisture content, such as tomatoes. This study confirms that EB irradiation, while maintaining postharvest quality, extends the shelf life of tomatoes by 5–10 days, suggesting its potential for commercial application in food preservation. [ABSTRACT FROM AUTHOR]

Abstract In this study, a feasibility of γ radiation detection using complementary metal-oxide semiconductor (CMOS) image sensors with a neural network algorithm to extract the γ rays interacted pixels has been investigated. The responses characteristics of the CMOS imaging sensor to γ-ray is studied by placed in a γ fields produced by standard60Co or137Cs isotope sources. The supported preview frame rate of the CMOS image sensor is 25 fps, establishing the functional relationship between the gray level histograms and the dose rate through the neural network, the high energy γ-ray from60Co and137Cs source radiation dose rate in µSv/h level can be detected using the CMOS imaging sensor. The results show that the proposed method can effectively identify the number of photon particles which detected by the radiation monitoring system based on CMOS image sensor, and infer that the CMOS imaging sensor with a radiation signal extraction algorithm can be used as a dose warner for radiation protection purpose.

Bridgman grown CsPbBr3 single crystals have demonstrated γ-ray spectra with a high resolution, making them a highly promising competitor for the current benchmark room-temperature radiation detector Cd1−xZnxTe. However, CsPbBr3 crystal growth is a very slow process that oftentimes results in cracked ingots due to phase transitions from cubic to orthorhombic crystal systems. In this report, we demonstrate the stabilization of a room-temperature cubic phase in Cs(Pb1−xSnx)(Br3−yCly) solid solutions to overcome this issue. Cs(Pb0.75Sn0.25)(Br1.00Cl2.00) was identified as the most promising composition and grown as a crack-free ingot using Bridgman growth in around one week. [ABSTRACT FROM AUTHOR]

We report the first‐time measurement of the electron‐hole pair (ehp) creation energy (Wehp) in novel Cd0.9Zn0.1Te0.98Se0.02 (CZTS) quaternary semiconductor. CZTS in single crystalline form is poised to be the future of large‐volume room‐temperature gamma‐ray detectors due to its excellent compositional homogeneity with highly reduced defects, high‐Z (atomic number) constituents, wide bandgap (1.6 eV), and superior charge transport properties. Despite a great deal of study of the material and device properties since its inception, the Wehp in CZTS has not been measured experimentally. Accurate determination of Wehp is essential for calibration of the spectrometer and other theoretical calculations. In this study we have used an absolute calibration approach, which is based on an iterative approach that yields the Wehp as the best‐fit parameter. Using a 241Am alpha emitting radioisotope and a planar CZTS detector, the Wehp in CZTS was calculated to be 4.47 eV. The obtained value has been validated by accurately predicting the peak energy for gamma rays emitted by a 137Cs source and read by a CZTS detector with different dimensions. The dependences of the calculated Wehp value on the detector dimensions, type of interaction, and effect of charge trapping are also discussed. [ABSTRACT FROM AUTHOR]

Neutrons are widely used in national defense, security, and medical health fields. It is critical to realize neutron detection with high efficiency. The most popular neutron detection scintillators such as lithium glass and 6LiF/ZnS:Ag screen exhibit insurmountable limitations: the former usually has relatively rather low light yield and latter is opaque. In this research, we report the successful construction of the novel full inorganic composite scintillators by low temperature co‐firing technology. The composite scintillator is derived from the ZnS:Ag and borate glass matrix, and it shows better transparency compared with the standard 6LiF/ZnS:Ag screen. It exhibits excellent scintillation properties with the X‐ray induced emission intensity of these composite scintillators reaching approximately 2.46 times of the standard Bi4Ge3O12 (BGO) crystal. The light output under thermal neutron excitation can reach 75 000 photons/neutron. In addition, it presents excellent neutron detection performance with natural abundance of 10B isotope. Our research findings can serve as a valuable reference for the advancement of robust neutron detection materials, particularly in the domain of ZnS:Ag‐based full inorganic scintillator for neutron detection. [ABSTRACT FROM AUTHOR]

We describe the advancement of fully depleted charge-coupled device (CCD) technology for scientific applications. Recent efforts on 650–725 (Formula presented.) m-thick CCDs for direct dark-matter and radiation detection with single-electron sensitivity are described, as well as the technology transfer of the fully depleted CCD technology to 200 mm-wafer fabrication facilities.

The combination of an ultra-low-loss optical fiber sensitive to ionizing radiation and an optical time domain reflectometer (OTDR) is investigated to explore the feasibility of a single-ended distributed radiation detector. The peculiarity of the tested fiber resides in its regenerative high radiation-induced attenuation (RIA) response in the infrared spectrum (1310 nm), which returns to a low value once the irradiation has ended, combined to its sensitivity, highly increasing with the dose rate. In this work, only some sections of the fiber line were irradiated with 100 kV X-rays at room temperature, to prove the spatially resolved radiation detection capabilities of the system. The transient RIA response of the fiber was characterized at different pre-irradiation doses. A pre-irradiation treatment was shown to stabilize the optical fiber response, improving its RIA vs. dose rate linearity and repeatability. This improved response, in terms of radiation quantification, comes at the cost of a lower detection threshold. This work lays the bases for a distributed radiation detector, with some capabilities in dose rate evaluation.

In order to adapt to the rapid development of high-speed imaging technology in recent years, it is very important to develop scintillators with an ultrafast time response. Because of its radiation-induced ultrafast decay time, ZnO has become an important material for radiation detection and dosimetry. According to different detection sources and application scenarios, ZnO is used in various radiation detectors in different structures, including nanoarrays and nanocomposites. In this paper, the synthesis methods and research status of various nanostructured ZnO-based materials and their applications in the detection of high-energy rays (X-rays, γ-rays) and high-energy particles (α, β and neutron) are reviewed. The performance discussion mainly includes spatial resolution, decay time and detection efficiency. [ABSTRACT FROM AUTHOR]

Gadolinium pyrosilicate (GPS, Gd2Si2O7) single crystals with different doping concentrations of Tb (0.1–2.0 mol%) are successfully fabricated using the floating-zone technique. In this work, the dependence of Tb-doping concentration on the photoluminescence (PL) and scintillation properties of Tb-doped GPS (Tb:GPS) has been investigated. The PL emission contour graph shows multiple emissions, with the strongest emissions at 378 nm for 0.1% and 0.5% Tb-doping and 544 nm for 1.0% and 2.0% Tb-doping, corresponding to Tb3+ 4f-4f transitions. The PL lifetimes of the specimens range from 4.89 to 5.22 ms. The scintillation spectra exhibit comparable wavelength and intensity trends to the PL emission. The scintillation lifetimes of the specimens range from 2.41 to 3.88 ms. The Tb:GPS specimens demonstrate a relatively excessive afterglow level, with Af20 values ranging from 1640 to 7250 ppm and Af40 values ranging from 136 to 362 ppm. Using recently developed pulse height measurement for millisecond decay scintillators, under excitation at 662 keV γ-rays, the 1.0% Tb:GPS specimen exhibits the highest scintillation light yield among all other specimens at 95,600 ph/MeV, making Tb:GPS one of the highest light yield oxide scintillators. [ABSTRACT FROM AUTHOR]

This research investigates the fabrication and analysis of plastic scintillators using an epoxy matrix. Plastic scintillators are widely used in radiation detection because of their low cost, ease of fabrication, resistance to moisture, and rapid decay time. The production process involved dissolving primary and secondary dopants, p-terphenyl (p-TP) and 1,4-bis [2-(phenyloxazolyl)]-benzene (POPOP), respectively, into a low-viscosity of cycloaliphatic amine as hardener B, which was then combined with Bisphenol-A diglycidyl ether as epoxy A. The ratio of primary and secondary dopants was varied in the experiment. The resulting scintillators were characterized using Fourier Transform Infrared Spectroscopy (FTIR) to analyze the functional groups that constitute the epoxy before and after curing. The morphology of the scintillator sample was evaluated using SEM and The thermal properties were evaluated with differential scanning calorimetry (DSC). The optical properties of the scintillator were studied using a UV-Vis Spectrophotometer and a Fluorescence Spectrophotometer. The performance of the scintillator in detecting gamma rays was evaluated using a module comprising a Photomultiplier Tube (PMT) and a Multichannel Analyzer (MCA) with sources of gamma Cesium 137. The results showed that epoxy-based scintillators can provide a detective response to gamma rays. This study demonstrates the potential of epoxy-based plastic scintillators for use in radiation detection. [ABSTRACT FROM AUTHOR]

Background: The increasing use of complex and high dose‐rate treatments in radiation therapy necessitates advanced detectors to provide accurate dosimetry. Rather than relying on pre‐treatment quality assurance (QA) measurements alone, many countries are now mandating the use of in vivo dosimetry, whereby a dosimeter is placed on the surface of the patient during treatment. Ideally, in vivo detectors should be flexible to conform to a patient's irregular surfaces. Purpose: This study aims to characterize a novel hydrogenated amorphous silicon (a‐Si:H) radiation detector for the dosimetry of therapeutic x‐ray beams. The detectors are flexible as they are fabricated directly on a flexible polyimide (Kapton) substrate. Methods: The potential of this technology for application as a real‐time flexible detector is investigated through a combined dosimetric and flexibility study. Measurements of fundamental dosimetric quantities were obtained including output factor (OF), dose rate dependence (DPP), energy dependence, percentage depth dose (PDD), and angular dependence. The response of the a‐Si:H detectors investigated in this study are benchmarked directly against commercially available ionization chambers and solid‐state diodes currently employed for QA practices. Results: The a‐Si:H detectors exhibit remarkable dose linearities in the direct detection of kV and MV therapeutic x‐rays, with calibrated sensitivities ranging from (0.580 ± 0.002) pC/cGy to (19.36 ± 0.10) pC/cGy as a function of detector thickness, area, and applied bias. Regarding dosimetry, the a‐Si:H detectors accurately obtained OF measurements that parallel commercially available detector solutions. The PDD response closely matched the expected profile as predicted via Geant4 simulations, a PTW Farmer ionization chamber and a PTW ROOS chamber. The most significant variation in the PDD performance was 5.67%, observed at a depth of 3 mm for detectors operated unbiased. With an external bias, the discrepancy in PDD response from reference data was confined to ± 2.92% for all depths (surface to 250 mm) in water‐equivalent plastic. Very little angular dependence is displayed between irradiations at angles of 0° and 180°, with the most significant variation being a 7.71% decrease in collected charge at a 110° relative angle of incidence. Energy dependence and dose per pulse dependence are also reported, with results in agreement with the literature. Most notably, the flexibility of a‐Si:H detectors was quantified for sample bending up to a radius of curvature of 7.98 mm, where the recorded photosensitivity degraded by (−4.9 ± 0.6)% of the initial device response when flat. It is essential to mention that this small bending radius is unlikely during in vivo patient dosimetry. In a more realistic scenario, with a bending radius of 15–20 mm, the variation in detector response remained within ± 4%. After substantial bending, the detector's photosensitivity when returned to a flat condition was (99.1 ± 0.5)% of the original response. Conclusions: This work successfully characterizes a flexible detector based on thin‐film a‐Si:H deposited on a Kapton substrate for applications in therapeutic x‐ray dosimetry. The detectors exhibit dosimetric performances that parallel commercially available dosimeters, while also demonstrating excellent flexibility results. [ABSTRACT FROM AUTHOR]

AbstractMachine learning has been found to be ubiquitously useful across many industries, presenting an opportunity to improve radiation detection performance using data-driven algorithms. Improved detector resolution can aid in the detection, identification, and quantification of radionuclides. In this work, a novel, data-driven, unsupervised learning approach is developed to improve detector spectral characteristics by learning, and subsequently rejecting, poorly performing regions of the pixelated detector. Feature engineering is used to fit individual characteristic photo peaks to a Doniach lineshape with a linear background model. Then, principal component analysis is used to learn a lower-dimension latent space representation of each photo peak where the pixels are clustered, and subsequently ranked, based on the cluster mean distance to an optimal point. Pixels within the worst cluster(s) are rejected to improve the full-width at half-maximum (FWHM) by 10% to 15% (relative to the bulk detector) at 50% net efficiency when applied to training data obtained from measurements of a 100 μCi 154Eu source using a H3D M400i pixelated cadmium zinc telluride detector.These results compare well with, but do not outperform, a greedy algorithm that accumulates pixels in order of FWHM from lowest to highest used as a benchmark. In the future, this approach can be extended to include the detector energy and angular response. Finally, the model is applied to newly seen natural and enriched uranium spectra relevant for nuclear safeguards applications. [ABSTRACT FROM AUTHOR]

Open Hardware-based microcontrollers, especially the Arduino platform, have become a comparably easy-to-use tool for rapid prototyping and implementing creative solutions. Such devices in combination with dedicated front-end electronics can offer low-cost alternatives for student projects, slow control and independently operating small-scale instrumentation. The capabilities can be extended to data taking and signal analysis at mid-level rates. Two detector realizations are presented, which cover the readouts of proportional counter tubes and of scintillators or wavelength-shifting fibers with silicon photomultipliers (SiPMs). The SiPMTrigger realizes a small-scale design for coincidence readout of SiPMs as a trigger or veto detector. It consists of a custom mixed signal front-end board featuring signal amplification, discrimination and a coincidence unit for rates of up to 200 kHz. The nCatcher transforms an Arduino Nano to a proportional counter readout with pulse shape analysis: time over threshold measurement and a 10-bit analog-to-digital converter for pulse heights. The device is suitable for low-to-medium-rate environments up to 5 kHz, where a good signal-to-noise ratio is crucial. We showcase the monitoring of thermal neutrons. For data taking and slow control, a logger board is presented that features an SD card and GSM/LoRa interface. [ABSTRACT FROM AUTHOR]

Ionizing radiation covers a broad spectrum of applications. Since radioactive/radiation pollution is directly related to radiation risk, radiation levels should be strictly controlled. Different detection methods can be applied for radiation registration and monitoring. In this paper, radiation-induced variations in the optical properties of silver-enriched PVA-based hydrogel films with and without azo dye (Toluidine blue O, TBO, and Methyl red, MR) additives were investigated, and the feasibility of these free-standing films to serve as radiation detectors/exposure indicators was assessed. AgNO3 admixed with PVA gel was used as a source for the radiation-induced synthesis of silver nanoparticles (AgNPs) in irradiated gel films. Three types of sensors were prepared: silver-enriched PVA films containing a small amount of glycerol (AgPVAGly); silver-enriched PVA films with toluidine blue adducts (AgPVAGlyTBO); and silver-enriched PVA films with methyl red additives (AgPVAGlyMR). The selection of TBO and MR was based on their sensitivity to irradiation. The irradiation of the samples was performed in TrueBeam2.1 (VARIAN) using 6 MeV photons. Different doses up to 10 Gy were delivered to the films. The sensitivity of the films was assessed by analyzing the characteristic UV-Vis absorbance peaks on the same day as irradiation and 7, 30, 45, 90, and 180 days after irradiation. It was found that the addition of azo dyes led to an enhanced radiation sensitivity of the AgNPs containing films (0.6 Gy−1 for AgPVAGlyTBO and 0.4 Gy−1 for AgPVAGlyMR) irradiated with <2 Gy doses, indicating their applicability as low-dose exposure indicators. The irradiated films were less sensitive to higher doses. Almost no dose fading was detected between the 7th and 45th day after irradiation. Based on the obtained results, competing AgNP formation and color-bleaching effects in the AgPVAGly films with dye additives are discussed. [ABSTRACT FROM AUTHOR]

Selective laser melting (SLM) technology is a promising additive manufacturing technology. However, due to the numerous influencing factors in this complex process, a reliable real-time method is needed to monitor the forming process of SLM. The molten pool is the smallest forming unit in the SLM process, the consistency of which can effectively reflect the quality of the printing process. By using a coaxial optical path structure and a compound amplifier circuit, high-speed acquisition of molten pool radiation can be realized. Next, single factor analysis and orthogonal experimentation were used to investigate the influence levels of key process parameters on the radiation of molten pool. In addition, numerical simulation was carried out with the same parameter setting schemes, the results of which are consistent with those in radiation detection experiments. It is shown that the laser power has the greatest effect on the radiation of the molten pool, while the scanning speed and the hatch spacing have little effect on the radiation. Finally, the positioning experiment involving the small hole structure was carried out, and the experimental results showed that the device could accurately locate the position coordinates of the given hole structure. [ABSTRACT FROM AUTHOR]

The photoluminescent properties of lanthanide complexes have been thoroughly investigated; however, there have been much fewer studies showcasing their potential use in ionizing radiation detection. In this work, we delve into the photo‐ and radio‐induced luminescence of a series of lanthanide‐bearing organic‐inorganic hybrids and their potential as a platform for X‐ray scintillation and imaging. The judicious synergy between lanthanide cations and 2,6‐di(1H‐pyrazol‐1‐yl)isonicotinate (bppCOO−) ligands affords six new materials with three distinct structures. Notably, Eu‐bppCOO‐1 and Tb‐bppCOO‐2 display sharp fingerprint X‐ray‐excited luminescence (XEL), the intensities of which can be linearly correlated with the X‐ray dose rates over a broad dynamic range (0.007–4.55 mGy s−1). Moreover, the X‐ray sensing efficacies of Eu‐bppCOO‐1 and Tb‐bppCOO‐2 were evaluated, showing that Tb‐bppCOO‐2 features a lower detection limit of 4.06 μGy s−1 compared to 14.55 μGy s−1 of Eu‐bppCOO‐1. Given the higher X‐ray sensitivity and excellent radiation stability of Tb‐bppCOO‐2, we fabricated a flexible scintillator film for X‐ray imaging by embedding finely ground Tb‐bppCOO‐2 in the polydimethylsiloxane (PDMS) polymer. The resulting scintillator film can be utilized for high‐resolution X‐ray imaging with a spatial resolution of approximately 7 lp mm−1. [ABSTRACT FROM AUTHOR]

Perovskites have attracted extensive attention as radiation detection material due to their long carrier diffusion length and lifetime, high absorption coefficient, and flexible manufacturing process. Compared with polycrystalline structures, single crystal perovskites improve the performance of optoelectronic devices due to their low defect state density, better photoelectric characteristics, and chemical stability. Herein, we review the recent progress of single crystal perovskite X-ray detectors. First, we briefly introduced the basic concepts, detection mechanisms, figure of merits of perovskite X-ray detectors, and the preparation methods of single crystal perovskites. Then, we summarized the significant advancements in single crystal perovskite X-ray detectors in recent times. Finally, we discussed the critical challenges and some practicable solutions for developing high-performance X-ray detectors. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), formed by the coordination of metal nodes and organic linkers, constitute a class of multifunctional materials with unprecedentedly high chemical/structural designability. Through properly harnessing the synergistic interplay between high atomic number nodes and functional linkers, radiation‐responsive MOFs have recently come on the scene, which can convert ionizing radiations (e.g., X‐ray, γ‐ray, β‐ray, α‐particle, and neutron) into electrical charges or visible light. Given the attributes of cost‐effectiveness, robust environmental stability, extensive chemical tunability, and diverse functionalities, cutting‐edge radiation‐responsive MOFs with remarkable electronic and optical properties have emerged as promising substitutes for conventional organic and inorganic radiation‐responsive substances in applications across biomedicine and technology. This review article documents recent advancements in radiation‐responsive MOFs by elucidating the foundational mechanisms governing electronic transport and photon conversion within frameworks through inherent node–linker and host–guest interactions prompted by high‐energy radiation. Furthermore, this review delves into state‐of‐the‐art applications that leverage newly formulated radiation‐responsive MOFs, capitalizing on precisely engineered component interactions to achieve efficient energy absorption, conversion, and emission. The rationale behind these developments is concluded and future opportunities for expanding the research of radiation‐responsive MOFs are simultaneously highlighted. [ABSTRACT FROM AUTHOR]

This research investigates the fabrication and analysis of plastic scintillators using an epoxy matrix. Plastic scintillators are widely used in radiation detection because of their low cost, ease of fabrication, resistance to moisture, and rapid decay time. The production process involved dissolving primary and secondary dopants, p-terphenyl (p-TP) and 1,4-bis [2-(phenyloxazolyl)]-benzene (POPOP), respectively, into a low-viscosity of cycloaliphatic amine as hardener B, which was then combined with Bisphenol-A diglycidyl ether as epoxy A. The ratio of primary and secondary dopants was varied in the experiment. The resulting scintillators were characterized using Fourier Transform Infrared Spectroscopy (FTIR) to analyze the functional groups that constitute the epoxy before and after curing. The morphology of the scintillator sample was evaluated using SEM and The thermal properties were evaluated with differential scanning calorimetry (DSC). The optical properties of the scintillator were studied using a UV-Vis Spectrophotometer and a Fluorescence Spectrophotometer. The performance of the scintillator in detecting gamma rays was evaluated using a module comprising a Photomultiplier Tube (PMT) and a Multichannel Analyzer (MCA) with sources of gamma Cesium 137. The results showed that epoxy-based scintillators can provide a detective response to gamma rays. This study demonstrates the potential of epoxy-based plastic scintillators for use in radiation detection.

Amorphous solids composed of B, C, N, and O, which are called BCNO, were developed as thermoluminescent (TL) materials for dosimetry. On the basis of X-ray diffraction patterns, the amorphous phase of the samples was confirmed. Photoluminescence spectra had an emission peak attributed to the electronic transition of emission centers based on a N vacancy and a C atom. A glow peak in TL glow curves was observed at around 380 K after X-ray irradiation. The result indicates that BCNO can be applied as tissue-equivalent TL materials for dosimetry. [ABSTRACT FROM AUTHOR]

This article details work performed on the synthesis and characterization of an inorganic mixed‐cation double halide perovskite, Cs2Ag.6Na.4In.85Bi.15Cl6 (CANIBIC). Single crystals have been created via a hydrothermal reaction, milled into a powder, and pressed into pellets, while nanocrystals have been directly synthesized via mechanosynthesis. A computational model is constructed to predict the X‐ray diffraction pattern of CANIBIC; this model aligns very well with the X‐ray diffraction pattern measured for CANIBIC crystal powder. This model can therefore be developed in the future as a tool to predict lattice parameters and crystal structures of other novel double‐halide perovskites. Photoluminescence spectra obtained from each format show broad emission centered at 630 nm, as is typical for self‐trapped exciton emission; self‐trapped exciton emission is also confirmed by investigating photoluminescence intensity as a function of laser power. Nanocomposites are produced via the loading of nanocrystals of CANIBIC into PMMA. Although nanocomposite disks consisting of a small proportion of CANIBIC nanocrystals in PMMA have a smaller mass attenuation coefficient than a pressed pellet of CANIBIC, these disks have comparatively bright radioluminescence due to their optical transparency. These nanocomposite disks are therefore a particularly useful format for the practical use of the CANIBIC scintillator. [ABSTRACT FROM AUTHOR]

Crystalline organic–inorganic hybrids, which exhibit colorimetric responses to ionizing radiation, have recently been recognized as promising alternatives to conventional X‐ray dosimeters. However, X‐ray‐responsive organic–inorganic hybrids are scarce and the strategy to fine‐tune their detection sensitivity remains elusive. Herein, an unprecedented mixed‐ligand strategy is reported to modulate the X‐ray detection efficacy of organic–inorganic hybrids. Deliberately blending the stimuli‐responsive terpyridine carboxylate ligand (tpc−) and the auxiliary pba− group with different ratios gives rise to two OD thorium‐bearing clusters (Th‐102 and Th‐103) and a 1D coordination polymer (Th‐104). Notably, distinct X‐ray sensitivity is evident as a function of molar ratio of the tpc− ligand, following the trend of Th‐102 > Th‐103 > Th‐104. Moreover, Th‐102, which is exclusively built from the tpc− ligands with the highest degree of π–π interactions, exhibits the most sensitive radiochromic and fluorochromic responses toward X‐ray with the lowest detection limit of 1.5 mGy. The study anticipates that this mixed‐ligand strategy will be a versatile approach to tune the X‐ray sensing efficacy of organic–inorganic hybrids. [ABSTRACT FROM AUTHOR]

Gadolinium pyrosilicate (GPS, Gd2Si2O7) single crystals with different doping concentrations of Tb (0.1–2.0 mol%) are successfully fabricated using the floating-zone technique. In this work, the dependence of Tb-doping concentration on the photoluminescence (PL) and scintillation properties of Tb-doped GPS (Tb:GPS) has been investigated. The PL emission contour graph shows multiple emissions, with the strongest emissions at 378 nm for 0.1% and 0.5% Tb-doping and 544 nm for 1.0% and 2.0% Tb-doping, corresponding to Tb3+ 4f-4f transitions. The PL lifetimes of the specimens range from 4.89 to 5.22 ms. The scintillation spectra exhibit comparable wavelength and intensity trends to the PL emission. The scintillation lifetimes of the specimens range from 2.41 to 3.88 ms. The Tb:GPS specimens demonstrate a relatively excessive afterglow level, with Af20 values ranging from 1640 to 7250 ppm and Af40 values ranging from 136 to 362 ppm. Using recently developed pulse height measurement for millisecond decay scintillators, under excitation at 662 keV γ-rays, the 1.0% Tb:GPS specimen exhibits the highest scintillation light yield among all other specimens at 95,600 ph/MeV, making Tb:GPS one of the highest light yield oxide scintillators.

Experimental data of the secondary radiation field and cosmic rays inside passenger aircraft in the atmosphere at airline altitudes (10-12 km) were processed. High-resolution data were measured by the semiconductor pixel detector Timepix operated in a miniaturized radiation camera MiniPIX-Timepix. The detector provides precise characterization with quantum sensitivity in terms of deposited energy and visualization of the charged particle radiation and X-ray field. The data were processed at the pre-processing and processing level with an integrated SW tool (Data Processing Engine-DPE). Results and physics data products consist of particle flux, dose rate, deposited energy, deposited dose, field composition into broad particle classes (protons, electrons, X-rays) as well as detailed visualization of the radiation field with quantum imaging registration of single-particle tracks. In this work, the detailed analysis of two measurements, as well as comparative graphs of selected results between ten flights are presented. Results of the total absorbed dose are compared with values measured also by Timepix detectors on ground and in LEO orbit onboard a satellite.

Intrinsic 40 K radioactive backgrounds from impurities of natural K in liquid scintillation cocktails have previously been demonstrated to limit their use in ultra-sensitive applications. This work explores two methodologies in parallel for the reduction of 40 K backgrounds in the cocktails, and lays the groundwork for use in ultra-sensitive applications. In one method, alternative low-K liquid scintillation matrix constituents were identified and in the other, a simple purification method for single components and finished cocktails was developed. Both methods were verified via ICP-MS analysis. Liquid scintillation counting of selected purified cocktails demonstrated background reduction, improved stability, and enhanced performance. The best performing purified cocktail was also counted on a custom-built ultra-low background liquid scintillation counter, with results below the detector background. [ABSTRACT FROM AUTHOR]