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The perovskite scintillators have been extensively studied recently for their merits of tunable emission spectra and simple preparation processes. However, the practical applications of perovskite scintillator-based X-ray image sensor are still impeded by inadequate radioluminescence, poor environmental stability, and low imaging resolution. Herein, we demonstrate a scalable co-firing method to fabricate high-quality lead-free Cs 3 Cu 2 I 5 perovskite scintillator and an Indium (In)-doping strategy is introduced to enhance its radioluminescence performance at the same time. The In-doped Cs 3 Cu 2 I 5 obtains a high PLQY of 77.9% and a relative light output of 53372 ph/MeV, which are 0.34 and 1.08 times higher than those of the undoped counterpart, respectively. The X-ray detection limit of the In:Cs 3 Cu 2 I 5 can reach 150.55 nGy air /s, 36.53 times lower than the requirement for X-ray medical diagnosis. The synthesized scintillator also shows superior stability under continuous high dose X-ray irradiation of 6800 μGy air /s for 120 minutes, maintaining 95% of its initial radioluminescence intensity. Furthermore, a large-area (300 cm2) flexible perovskite scintillator film is prepared, which owns a much competitive resolution of 10 lp/mm and less distortion in X-ray imaging. This work provides a practical path for the wide application of perovskite scintillator in the field of X-ray detection and imaging in near future. [Display omitted] • A co-firing method for lead-free indium doped Cs 3 Cu 2 I 5 perovskite scintillators has been proposed. • The indium doped Cs 3 Cu 2 I 5 shows superior environmental and radiation stability. • A large-area flexible scintillator film is prepared for high-resolution imaging. [ABSTRACT FROM AUTHOR]

LaMgAl 11 O 19 :Er single crystals were examined as candidates for scintillators emitting near-infrared luminescence, and their radioluminescence and scintillation detector characteristics were assessed. Upon exposure to X-ray, distinct emission peaks appear at ∼550 and ∼1540 nm and are attributable to Er3+ ions. The decay curves also exhibited characteristic decay times associated with Er3+ ions. Particularly, the 3% Er-doped sample showed a discernible linearity in the dynamic range of dose rate from 1 to 50,000 mGy/h, indicating the potential utility in applications requiring precise and reliable radiation measurements. • Er-doped LaMgAl 11 O 19 crystals were synthesized by the floating zone method. • The samples show a broad emission band at 380 nm due to host and sharp peaks at 550 and 1540 nm due to Er3+. • The 3% Er-doped sample showed a good linearity in the dynamic range of dose rate from 1 to 50,000 mGy/h. [ABSTRACT FROM AUTHOR]

Thorium-227 was separated from its progeny and standardized for activity by the triple-to-double coincidence ratio (TDCR) method of liquid scintillation counting. Confirmatory liquid scintillation-based measurements were made using efficiency tracing with 3H and live-timed anticoincidence counting (LTAC). The separation time and the efficiency of the separation were confirmed by gamma-ray spectrometry. Calibrations for reentrant pressurized ionization chambers, including commercial radionuclide calibrators, and a well-type NaI(Tl) detector are discussed. • Th-227 was separated from progeny and standardized for activity. • The pre-equilibrium standard was based on TDCR liquid scintillation counting. • Confirmatory measurements by efficiency tracing and anticoincidence counting. • Time-dependent calibrations for radionuclide calibrators and NaI(Tl) well counters. • A bilateral comparison showed consistency with the NPL activity standard. [ABSTRACT FROM AUTHOR]

• HfTiO 4 transparent thick film phosphor was epitaxially grown using CVD method. • Deposition rate of HfTiO 4 film was reached 36 µm h−1. • HfTiO 4 films with Eu3+, Dy3+, and Tb3+ exhibited red, yellow, and green emissions. Hafnium (Hf)-based double oxides show promise as high-efficiency scintillators due to large effective atomic numbers and high relative density. However, the preparation of these scintillation crystals is challenging due to their high melting points and incongruent melting behavior. In the present study, we demonstrated that the chemical vapor deposition (CVD) of single-phase HfTiO 4 films on quartz glass substrate was successfully deposited at temperatures ranging from 973 to 988 K, with a TiO 2 molar ratio in the precursor vapor of 25–45 mol% TiO 2. The deposition rate of HfTiO 4 reached 36 µm h−1. The films exhibited an in-line transmittance of 78 % relative to the raw glass substrate at a wavelength of 600 nm. When activated with Eu3+, Dy3+, and Tb3+ ions, the HfTiO 4 films displayed red, yellow, and green photoluminescence emissions originated from the 4f–4f transitions of each trivalent rare-earth ion under ultraviolet light irradiation. HfTiO 4 exhibited no intrinsic background emission, suggesting that the addition of a selected activator could yield a phosphor with the desired emission color range. [ABSTRACT FROM AUTHOR]

[Display omitted] • MAPbBr 3 NCs are in-situ space-confined encapsulated in metal–organic frameworks. • bMOF⊃MAPbBr 3 realizes room-temperature scintillation and exceptional X-ray imaging. • bMOF⊃MAPbBr 3 shows enhanced stability against various stimuli and X-rays. • The role of the MOF and the mechanism of improved performance are elucidated. The development of perovskite nanocrystals (NCs) based composites with enhanced stability and exceptional photoelectric properties is of great significance for their application in scintillators for X-ray imaging, but it remains challenging. Herein, we demonstrate a novel and stable scintillator, achieved through a host–guest strategy involving the confinement of perovskite NCs, e.g., MAPbBr 3 NCs, in metal–organic frameworks (MOFs). The host MOF, bio-MOF-100 (denoted as bMOF), facilitates the in-situ space-confined formation of MAPbBr 3 NCs while providing quantum confinement, surface passivation, and protection to these guests. This host–guest strategy results in high exciton binding energy, bright and efficient luminescence, and significantly enhancing their stability against various factors such as air, heat, UV, solvents and X-ray irradiation. Consequently, this advancement prompts the transition of their application scenarios from the colloidal state to the solid state. The bMOF⊃MAPbBr 3 scintillator exhibits a linear response to X-ray with a detection limit determined to be 170 nGy air s−1. Moreover, the bMOF⊃MAPbBr 3 –PMMA scintillator screen demonstrates high-quality X-ray imaging with an impressive spatial resolution of 14.7 lp mm−1. This work provides a new avenue for the development of perovskite NCs-based host–guest composites and paves the way for the broader implementation in solid-state optoelectronic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new 3D organic supramolecule constructed by unique halogen bonding and π–π interactions is obtained. • Dual phosphorescent emission mechanism of the supramolecule is explained. • This supramolecule shows highly stable UOP property that can be applied directly in extreme environments. Ultralong organic phosphorescence (UOP) materials have offered new exciting possibilities in the fields of photoelectric device, scintillators, anti-counterfeiting and bioprobe. However, pure organic phosphorescent materials inevitably suffer from rapid nonradiative transitions under oxygen, humidity, and high temperature, rending their phosphorescence is significantly quenched. Herein, a three-dimensional (3D) organic supramolecule (named SFIz) featuring UOP property was constructed successfully. Impressively, benefiting from the unique halogen bonding and π–π interactions, dual phosphorescent emission route of high energy state T 1 (Br···O interaction predominates) and low energy state T 1 * (π–π interaction predominates) was simultaneously realized. Furthermore, owing to the robust supramolecular structural characteristic, SFIz shows highly stable UOP property with remarkably thermal, force stimulus and water-resistant stabilities that can be applied directly in extreme environments such as high temperatures 453 K (180 °C), high pressure and humidity. This work not only provides a much needed solution for achieving highly stable UOP materials and promoting their applications in extreme environments, but also gives in-depth understanding of both UOP and dual phosphorescent emission mechanisms in a non-metallic organic molecule. [ABSTRACT FROM AUTHOR]

This paper presents a study on the salinity determination and flow rate estimation in a two-phase air-water system. For this purpose, an automated air-water test loop capable of generating different flow patterns in a horizontal pathway was utilized to do numerous experiments at varying flow rates. A nuclear measuring setup, comprising Cs-137 and Am-241 as radiation sources, one NaI (Tl) scintillation detector to register transmission counts of Cs and three scintillator detectors for registering transmission and scattering counts from Am, was prepared. A pressure drop pipe was also employed for flow rate measurement, with MLPs were selected as the processing element. Notable innovations of this paper can be considered from two perspectives. Firstly, a novel paradigm in nuclear measurement geometry. This novelty uses the benefits of three scintillator detectors to extract features with the maximum potential for classifying and determining salinity. Secondly, there is a new method in data processing and utilizing optimum features to achieve the best performance in predicting flow rates. Results in flow rate prediction independent of salinity and flow regime indicate that the proposed paradigm and method are reliable for using in industrial fields related to multi-phase metering. • This paper proposes a novel paradigm in nuclear measurement geometry. • This paper employs seven ANNs to develop the optimal prediction model. • The combination of wavelet transform and statistical features shows the best performance to determine the flow rates. • The results indicated that the proposed prediction model achieved an MAE of less than 4/237 L/min and an MRE% of 4/842 % for predicting flow rates. [ABSTRACT FROM AUTHOR]

We have developed LiAlO 2 nanoparticle-loaded polystyrene-based plastic scintillators for neutron detection and evaluated the neutron detection properties. The size of LiAlO 2 nanoparticles was ∼150 nm. The distribution of nanoparticles in the plastic scintillator was uniform in the horizontal direction but non-uniform in the vertical direction. The emission peak was observed around 420 nm in the scintillation spectra and is attributed to1,4-Bis[2-(5-phenyloxazolyl)] benzene (POPOP) included as an organic phosphor. The 10 wt% LiAlO 2 nanoparticle-loaded plastic scintillators containing 22 wt% 2,5-Diphenyloxazole (DPO-POPOP (the molar ratio of 80:1) had the highest light yield of 1600 photons/neutron, which is significantly higher than that of a commercially available 10B-loaded plastic scintillators (BC-454) having a light yield of 800 photons/neutron. • We developed LiAlO 2 nanoparticle-loaded plastic scintillators for neutron detection. • The light yield of 1600 photons/neutron was achieved. • The size of LiAlO 2 nanoparticles was ∼150 nm. [ABSTRACT FROM AUTHOR]

Rare-earth aluminate garnet-type double oxides have practical applications as scintillators with high luminescence yields; however, several garnet compounds are metastable phases, and those scintillation properties are yet unclear. We prepared Ce3+-doped Gd 3 Al 5 O 12 (Ce3+:GAG) as a thick-film phosphor, using laser-assisted metal–organic chemical vapor deposition, and investigated its luminescence and scintillation properties. With a deposition rate of 48 μm h−1, the Ce3+:GAG thick film was epitaxially grown on a Y 3 Al 5 O 12 single crystal substrate with in-plane orientation relationship. Under UV light and α-ray irradiations, the Ce3+:GAG film exhibited a broad emission centered at 560 nm corresponding to the 5d–4f transition of Ce3+ ions. The scintillation light yield of the Ce3+:GAG film was 14250 photons per 5.5 MeV with a fast decay constant of 82.8 ns for the α-ray irradiation from the 241Am source. • Ce3+:GAG thick film phosphor was epitaxially grown using CVD method. • Ce3+: GAG exhibited photoluminescence at 560 nm due to Ce3+ 5d-4f transition. • Scintillation light yield was 14250 photons per 5.5 MeV, comparable to Ce3+:YAG. [ABSTRACT FROM AUTHOR]

In a compact multi-radiation imaging system, the substitution of traditional charge-coupled devices with a plastic scintillators array coupled with silicon photomultiplier detectors significantly enhances the radiation tolerance of the detection and imaging module, thereby reducing the system footprint. We present a detailed structure of a compact fast neutron/gamma-ray dual-modality imaging system based on a plastic scintillators array and evaluate its performance in imaging various samples. The detector array consists of nine 14.7 × 14.7 × 100 mm3 EJ-276 plastic scintillators coupled with corresponding silicon photomultiplier units, arranged in a 3 × 3 grid. The usage of EJ-276 plastic scintillators allows for discrimination between neutron and gamma signals through pulse shape discrimination techniques, enabling data separation between neutrons and gamma rays. In this paper, we present the experimental procedure and results of fast neutron-gamma imaging for objects containing aluminum and polyethylene materials. Fast neutrons and gammas are delivered by an Cf-252 source. The experimental results demonstrate that the system achieves dual-modality grayscale imaging and has resolution for sample thickness. Reconstructed image contrast allows qualitative differentiation of sample materials, especially detecting low-Z materials encapsulated by high-Z materials. [ABSTRACT FROM AUTHOR]

High-speed X-ray imaging can be used to observe the internal evolution of objects in the microsecond range. However, obtaining data and processing images continuously are difficult when the speed of X-ray imaging is more than one million frames per second (fps). The novel method of high-speed X-ray imaging, which is based on a SiPM auto-encoding detector, was proposed. The different response to X-ray is realized by adjusting the bias voltage of different pixels to encode the analog signals. The analog signals from multiple SiPM pixels are simplified into a single signal. In this way, SiPM is constructed as the SiPM auto-encoding detector, which greatly reduces the amount of analog signals to be sampled for each frame of X-ray image, and then the image is reconstructed in the upper computer. The feasibility of the imaging method was verified by coupling the pixelated SiPM and lutetium-ytterbium scintillation crystals to construct a SiPM auto-encoding detector. Six patterns were exposed when pulsed X-rays were performed at frequencies of 100 and 500 kHz. Then, the number of image pixels was compressed from 16 to 4. The peak signal-to-noise ratio of the reconstructed images was above 41, and the structural similarity was above 0.99. Experimental results demonstrated that the speed of continuous X-ray imaging reached 500, 000 fps for six kinds of 4 × 4 pixel patterns. This method can be applied to improve the speed of high-speed continuous X-ray imaging. [ABSTRACT FROM AUTHOR]

The response of a gamma-ray spectrometer is generally determined by analyzing full-energy peaks. However, full-energy peaks cannot be measured easily in the case of scintillation detectors that consist of light elements, such as glass scintillators. Only a strong Compton plateau appears in the spectrum of such detectors. Therefore, Compton edgers were used to evaluate the response of these detectors. The response of a low-resolution 6 Li-glass detector to gamma rays was measured for the first time by a coincidence method with a high-resolution LaBr 3 :Ce detector using cascade gamma rays (2.75 and 1.37 MeV) from a 24Na source. Coincidence gates were applied at the peaks of the spectrum of the LaBr 3 :Ce detector at the 0.51 MeV annihilation peak, and the sum peaks of a gamma ray and a backscattered gamma ray. By analyzing the gated spectra of the 6 Li-glass detector, the energy-dependent detector response (i.e., the output strength and its dispersion) was determined. • Evaluation of the response characteristics, including signal output and broadening, of a low-resolution 6Li-glass detector to gamma rays up to approximately 2.5 MeV. • Coincidence measurement of cascade gamma rays emitted from a 24Na source with a high-resolution detector, a LaBr 3 :Ce detector. • Peak analysis of the spectra of the 6Li-glass detector gated at gamma ray peaks of the LaBr3:Ce detector. [ABSTRACT FROM AUTHOR]

Gamma detectors consisting of lanthanum bromide (LaBr 3) scintillator and silicon photomultiplier (SiPM) have extensive applications in various scientific fields. Accurate gamma energy measurement depends on accurate calibration of these detectors. While some studies have attempted detector self-calibration based on the natural background of LaBr 3 , these methods are limited to specific LaBr 3 crystals and lack generality. To address this limitation, this paper proposes a self-calibration method that solely utilizes the natural radioactivity of 138La. By solving for the maximum similarity between the test background from measurement and the standard spectrum obtained from the Geant4 simulation, the detector is effectively calibrated. Furthermore, the application of a series of energy spectrum processing algorithms simplifies the solution complexity of the maximum similarity problem. Experimental results from four different crystals at varying temperatures demonstrate calibration errors of less than 0.8% at 662 keV, highlighting the method's broad applicability and accuracy. Besides, the influence of the background measurement time and the natural environmental background on the self-calibration method are discussed in detail, further illustrating the value of the application. [ABSTRACT FROM AUTHOR]

NaI:Tl,6Li bulk crystals are regarded as promising neutron-gamma (n-γ) scintillators because of low production cost and superior n-γ pulse shape discrimination (PSD) performance. In this work, some rare earth elements (Gd, Y, Lu and Sc) co-doped NaI:Tl,6Li single crystals were grown by the multi-ampoule Bridgman method. It was found that the rare earth co-doping significantly improves the pulse height discrimination (PHD) capability of NaI:Tl,6Li with high alpha/beta (α/β) ratio, approaching to 100%. The optimal α/β ratios achieved for Gd, Y, Lu and Sc co-doped NaI:Tl,6Li are 0.85, 0.93, 0.95, and 0.83, respectively. Electron equivalent energy per neutron interaction is above 3.96 MeV and can be as high as 4.54 MeV, close to the Q value of 4.78 MeV for 6Li(n, α)3H interaction. Moreover, the rare earth co-doped NaI:Tl,6Li crystals still maintain the superior PSD capability with figure of merit (FoM) in the range of 2.1–3.3. These results highlight the great potential of rare-earth co-doped NaI:Tl,6Li crystals serving as high-performance n-γ scintillators. [ABSTRACT FROM AUTHOR]

Fast electronic readout for high-channel density scintillator-based systems is needed for radiation tracking and imaging in a wide range of applications, including nuclear physics, nuclear security and nonproliferation. Programmable electronics, like FPGAs and ASICs, provide a fast way of conditioning and processing the signal in real time. In this paper, we present a pulse shape discrimination (PSD) method based on the shaping circuit of a commercially available ASIC, the Citiroc1A by CAEN Technologies. We used two different shaping times per detector channel to calculate a shaping parameter that enables PSD. Using our new method, neutron and gamma-ray pulses detected by a d 12 -stilbene scintillator can be effectively discriminated at light output values greater than 0.15 MeVee. While not achieving the PSD performance of traditional offline charge integration, our method does not require the transfer of data to a separate system for further processing and enables the direct deployment of high-channel density multi-particle detection systems. Moreover, the availability of a wider range of shaping times than those on the Citiroc1A can potentially further improve the PSD performance. [ABSTRACT FROM AUTHOR]

Experiments such as mu2e (FNAL, USA) and COMET (KEK, Japan) seek the direct muon-to-electron conversion to study Charged Lepton Flavor Violation processes. A highly efficient (up to 99.99% efficiency) cosmic muon detection system is needed to achieve a single-event sensitivity below 1 0 − 17 . In this article, the possibility of attaining such efficiency in the short and long term is discussed for modules based on 7-mm- or 10-mm-thick and 40-mm-wide plastic scintillation strips with a single 1.2 mm WLS fiber glued into the groove along the strip and using MPPC/SiPM for light detection. A Simplified Light Yield Distribution (SLYD) method to estimate the efficiency of the module is proposed, and the simulation results obtained with GEANT 4 for a system based on a 4-by-4 array of 7x40x3000 mm strips are compared with the experimental data. It is found that for the systems requiring efficiency of 99.99% and higher, it is important to improve the light yield as much as possible and to achieve the smallest possible gap between neighbor scintillation volumes is important. [ABSTRACT FROM AUTHOR]

Signal saturation in the Silicon PhotoMultiplier (SiPM) often causes a serious problem in using a detector equipped with SiPMs for scintillator readout. Conventionally, SiPM signal saturation is measured through direct injection of visible light pulses to the SiPM. However, the method works poorly with the scintillation detector because the effects of the time constant of the emission of scintillation light are not included. Here, we present a novel method to measure the precise degree of SiPM signal saturation in scintillation detectors. The key difference from the conventional method is to use UV light pulses, as opposed to visible light ones, to inject and excite scintillation light in the detector. It allows us to directly measure the degree of saturation in situ taking into account all the major effects in the detector, such as the time constant of the scintillation emission. We also develop a new model for SiPM signal saturation and validate it with the measured degree of saturation with the above-mentioned new method. [ABSTRACT FROM AUTHOR]

This work aims at the investigation of the Pulse Shape Discrimination (PSD) capabilities of two very compact detection systems composed of a 3x3x3 cm3 EJ 276 and a 3x3x3 cm3 EJ 276G (the latter green shifted version) plastic scintillators, both coupled to Silicon Photomultiplier (SiPM). The studied systems are supposed to be the basic elementary cell of a new multi-detector for simultaneous detection of neutrons and light charged particles called NArCoS (Neutron Array for Correlation Studies) having both high angular and energy resolution. In this perspective, the results of the experimental qualification of two prototypes with gamma and alpha radioactive sources and in beam tests are reported, in order to characterize the optimum choice for the new device. [ABSTRACT FROM AUTHOR]

For measuring activity of radionuclides produced in High-flux Advanced Neutron Application Reactor (HANARO) at the Korea Atomic Energy Research Institute (KAERI), a small size 4 π β – γ coincidence counter was developed. This counter comprises a liquid scintillator for detecting beta-ray and NaI crystal for detecting gamma-ray, each coupled to SiPMs (silicon photomultipliers) that do not require high-voltage devices. The performance of the newly developed detector was validated using 134Cs and 177Lu reference materials. [ABSTRACT FROM AUTHOR]

This paper aims to demonstrate the feasibility of the proposed compensated neutron logging (CNL) tool for the absolute measurement of the porosity of subsurface formation based on the computational simulation study. Conventional CNL tools use 3He gas detectors, but solid-state scintillation detectors such as stilbene and CLYC are explored in this study. Monte Carlo simulations were conducted to investigate the advantages of the proposed CNL tool and the effects of environmental parameters such as pore fluid, borehole radius, and rock type on the absolute porosity measurement. Comparing simulated responses from the stilbene and CLYC detectors with conventional 3He detector, the stilbene-based logging system was expected to exhibit the highest neutron detection efficiency, while the porosity calibration performance was evaluated to be better with the CLYC-based system. Pore fluid makes differences in porosity calibration curves associated with the hydrogen content. Larger borehole radius deteriorates the porosity calibration performance. The shape of porosity calibration curve was altered for a certain rock type. Neutron-induced gamma spectroscopy may reveal the rock type information based on gammas from certain elements. One can identify the rock type from the CLYC results based on photopeaks from silicon, which may be relatively hard to accomplish with the stilbene-based system. The proposed system is expected to allow absolute porosity measurement in a broader environmental configuration compared to the conventional system. [ABSTRACT FROM AUTHOR]

We have developed a compact detector for measuring beam particles using plastic scintillators readout through Multi-Pixel Photon Counters, which is employed for hypernuclear measurements in the WASA-FRS experiment at GSI. The Time-of-Flight resolution of the newly-developed detector has been investigated in relation to the overvoltage with respect to the breakdown voltage, a maximum counting rate of approximately 3 × 1 0 6 /s per segment, and a maximum beam charge of Z = 6. The evaluated Time-of-Flight resolutions between the neighboring segments of the detector range from 44. 6 ± 1. 3 ps to 100. 3 ± 3. 6 ps (σ) depending on the segment, overvoltage values, and beam intensity. It is also observed that the Time-of-Flight resolution is inversely correlated to the beam atomic charge (Z). [ABSTRACT FROM AUTHOR]

The discrimination of α / β -particles based on Liquid Scintillation (LS) is a measurement technique that can be applied for environmental monitoring. This technique relies on the specific feature of the scintillation process yielding two decay components (fast and delayed) of the photon emission following a particle interaction in a LS sample; indeed, the intensity of the delayed component is higher for α -particles than for β -particles. When operating with a photon detector such as a PhotoMultiplier Tube (PMT), the Pulse-Shape Discrimination (PSD) is the traditional approach, relying on low-pass filtered signals allowing pulse-tail analysis for an α -particle identification. This paper presents a new α -particle detection method based on an Artificial Neural Network (ANN) that directly processes fast pulse trains produced by the delayed scintillation component of a single detector. The ANN is trained using an experimental dataset obtained with a single PMT channel connected in a 3-PMTs detection system from which triple coincidences resulting from α -interactions ( 241 A m) in a LS source are used for the single detector labeling. As we target a real-time implementation, the ANN is designed to minimize the computational resources. The classifier can operate with good performances (91.0% of correct classification, 8.5% false negative and 0.5% false positive) on a single-channel detector. [Display omitted] • Focus on the photons train from a scintillator instead of the integrated pulse shape. • α / β discrimination relying on an ANN which analyses the signal from a single PMT. • Training dataset labelization based on coincidence detection. • The coïncidence detection is performed using a 3-PMT TDCR experimental layout. [ABSTRACT FROM AUTHOR]

Liquid argon time projection chambers (TPC) are widely used in neutrino oscillation and dark matter experiments. Detection of scintillation light in liquid argon TPC's is challenging because of its short wavelength, in the VUV range, and the cryogenic temperatures (∼ 86 K) at which the sensors must operate. Wavelength shifters (WLS) are typically needed to take advantage of the high Photon Detection Efficiency (PDE) in the visible range of most of photondetectors. The Hamamatsu VUV4 S13370–6075CN SiPMs can directly detect VUV light without the use of WLS, which main benefit is an improved PDE at these short wavelengths, but also the visible light from WLS. The manufacturer (Hamamatsu Photonics K.K.) provides a complete characterization of these devices at room temperature; however, previous studies have indicated a decrease of the PDE at cryogenic temperature for VUV light. In this work, we present the measurement of the PDE of VUV4 SiPMs at cryogenic temperature for different wavelengths in the range [270, 570] nm. A dedicated measurement at 127 nm is also shown. [ABSTRACT FROM AUTHOR]

Contrast-enhanced computed tomography (CT) is an indispensable technique in modern diagnostic medicine because it not only allows non-destructive, three-dimensional observation of the inside of the body but also provides images that highlight lesions. Recent developments in photon-counting (PC) CT systems have enabled contrast-enhanced CT scanning and quantitative evaluations, such as material discrimination and concentration estimation of contrast agents, using X-ray energy information. We established a PC-CT system that combines fast scintillators and multipixel photon counters (MPPCs) and demonstrated its performance. In this paper, we report the imaging performance of a PC-CT system using a mixture of contrast agents containing gadolinium and iodine. We performed CT imaging of a static phantom containing a mixture of the two contrast agents. The concentration of each contrast agent from the CT images in multiple energy bands were estimated. We succeeded in obtaining the concentration distributions for each contrast agent and verified the possibility of discriminating between two substances with different atomic numbers. In addition, the same procedures and analytical methods used for the static phantom were applied to the in vivo imaging of a mouse, in which gadolinium- and iodine-containing contrast agents were injected at different time intervals. We also succeeded in discriminating between the two contrast agents in vivo, making it possible to provide new imaging diagnostics such as the determination of necrotic tissues and normal blood vessels. Furthermore, we succeeded in creating three-dimensional concentration maps of gadolinium and iodine in a mouse, demonstrating the great potential of MPPC-based PC-CT for future clinical applications. • A silicon photomultiplier-based photon-counting CT system was established. • The concentration of iodine and gadolinium mixed contrast agents can be estimated. • Correction by Monte Carlo simulation improves the accuracy of the estimation. • The transition of the two contrast agents flowing in vivo is visualized. [ABSTRACT FROM AUTHOR]

Radiation source localization is important for nuclear nonproliferation and can be obtained using time-encoded imaging systems with unsegmented detectors. A scintillation crystal can be used with a moving coded-aperture mask to vary the detected count rate produced from radiation sources in the far field. The modulation of observed counts over time can be used to reconstruct an image with the known coded-aperture mask pattern. Current time-encoded imaging systems incorporate cylindrical coded-aperture masks and have limits to their fully coded imaging field-of-view. This work focuses on expanding the field-of-view to 4 π by using a novel spherical coded-aperture mask. A regular icosahedron is used to approximate a spherical mask. This icosahedron consists of 20 equilateral triangles; the faces of which are each subdivided into four equilateral triangle-shaped voxels which are then projected onto a spherical surface, creating an 80-voxel coded-aperture mask. These polygonal voxels can be made from high-Z materials for gamma-ray modulation and/or low-Z materials for neutron modulation. In this work, we present Monte Carlo N-Particle (MCNP) simulations and simple models programmed in Mathematica to explore image reconstruction capabilities of this 80-voxel coded-aperture mask. [ABSTRACT FROM AUTHOR]

Lead halide perovskites are reportedly a very promising group of materials for scintillation due to their fast sub-nanosecond exciton luminescence, small band-gaps, and high theoretical light yield. Unfortunately, they only show emission at cryogenic temperatures. In this work single crystals of CsPbBr 3 and CsPbCl 3 are studied at cryogenic temperatures. Upon comparing the 10 K emission spectra measured under X-ray and UV–vis excitation, a new near-infrared emission was found for both CsPbBr 3 and CsPbCl 3 only present under X-ray excitation. The integral light yields of CsPbBr 3 and CsPbCl 3 at 10 K are estimated to be 34,000 and 2,200 photons/MeV under 40 keV X-ray excitation, respectively. The main components of the light yield of CsPbBr 3 at 10 K are the near band-gap free exciton emission that suffers from self-absorption and the broad near-infrared emission that falls outside the typical detection range of a photo-multiplier tube. Due to the combination of the two aforementioned effects it was not possible to measure a γ -ray pulse height spectrum for CsPbBr 3 at 10 K. Despite all the suitable properties, like the fast decay, a small band-gap, and the positive prospects of 3D perovskite based scintillators, we conclude that these materials perform poorly as scintillation crystals. [ABSTRACT FROM AUTHOR]

This paper presents a comprehensive bibliometric analysis to understand the evolution of scintillators as neutron detection from 2014 to 4 July 2023, utilizing data sourced from Scopus. The 312 selected articles were visualized using vosViewer and Tableau. This study delves into critical aspects, such as the growth of publication in this field over time, contributions made by various countries and their collaborative networks, top journals publishing articles related to scintillators as neutron detection, frequently cited documents used as references, and research trends over specific periods. The results show that research on scintillators for neutron detection has been popular since 2014, with at least 20 articles published yearly. The United States, China, France, and Italy have published the most papers, but Lithuania, Russia, India, and China have been the most active recently. The article provides researchers with an extensive overview of their field. This information empowers them to identify research gaps and find collaborators more efficiently. Overall, this analysis serves as a valuable resource for researchers seeking to advance their understanding of scintillators as neutron detection. • Evolution of scintillators as neutron detection from 2014 to 4 July 2023. • Scintillators for neutron detection popular since 2014 with 20 articles published yearly. • The United States, China, France, and Italy have published the most papers. • Lithuania, Russia, India, and China have been the most active recently. • This information to identify research gaps and find collaborators more efficiently. [ABSTRACT FROM AUTHOR]

A compact neutron spectrometer consisting of a 6 mm × 6 mm × 120 mm prism of EJ-276 plastic scintillator capable of pulse shape discrimination coupled to a single silicon photomultiplier is described. In principle this device will be capable of spectroscopic measurements exceeding 100 MeV using unfolding analyses with detector response functions measured at neutron time-of-flight facilities. A characterisation of the device is described and illustrated with measurements of the detector response made at three fast neutron facilities with energies between 5.0 MeV and 63.5 MeV. Nearly mono-energetic detector response functions were used to produce neutron energy spectra by unfolding light output distributions measured with the detector in the energy range of interest. • A compact high energy neutron detector was developed featuring EJ-276 scintillator and a single silicon photomultiplier. • The device features excellent pulse shape discrimination to select neutron events from gamma ray events. • The device was characterised in a cyclotron facility with high energy neutrons, selected by time-of-flight. • Excellent spectrometry is achieved through unfolding using measured response functions. [ABSTRACT FROM AUTHOR]

0.5, 1, 2, and 5% Er-doped La 3 Ga 5 SiO 14 (LGS) single crystals were synthesized by the Floating Zone method and the photoluminescence (PL) and scintillation properties were characterized. Emission peaks appeared at visible–near-infrared (NIR) regions. Their spectral features matched with those due to the 4f–4f transitions of Er3+. The PL quantum yields of 0.5, 1, 2, and 5% Er-doped samples were respectively 45.0, 73.3, 82.5, and 69.4%. The decay times due to the 2H 9/2 –4I 15/2 transitions of Er3+ were obtained when visible ranges were monitored under excitation of both visible lights and X-rays. All the prepared samples showed good linearity between the X-ray exposure dose rate and scintillation signals in NIR ranges. The best lower detection limit in prepared samples was 5 mGy/h recorded by the 2% Er-doped LGS. • Er-doped La 3 Ga 5 SiO 14 single crystals were synthesized by the Floating zone method. • Luminescence due to 4f–4f transitions of Er3+ was observed in both visible and near-infrared regions. • Quantum yields of 0.5, 1, 2, and 5% Er-doped samples were respectively 45.0, 73.7, 82.5, and 69.4%. • The best lower detection limit in prepared samples was 5 mGy/h obtained by 2% Er-doped sample. [ABSTRACT FROM AUTHOR]

A new scintillator based fast-ion loss detector (FILD) system has been designed for the Wendelstein 7-X (W7-X) stellarator. The mechanical design of the system is presented here along with engineering analyses of the system. This includes an assessment of the structural loads which also considers electromagnetic forces calculated for possible disruption scenarios as well as a mode frequency analysis of the system. Furthermore, an analysis of the thermal characteristics of the actively cooled probe head under prescribed steady state and transient heat loads is presented. Finally, the optical relay system is described and its properties used to forward model synthetic camera signals using the FILDSIM code and based on theoretical fast-ion losses incident on the probe head calculated using the ASCOT5 code. [ABSTRACT FROM AUTHOR]

• The neutron energy response of Cs 2 7LiYCl 6 :Ce (CLYC-7) scintillation detector was investigated, and the figures-of-merit (FOM), response function, and neutron energy resolution at different neutron energies were obtained. • The Monte Carlo method was used to simulate the particle transport within the CLYC-7 scintillator and investigate the energy response curves of different particles. • The response function was applied to the CLYC-7 scintillation detector, and it was used to measure the D-D fusion neutron spectrum on EAST. During plasma experiments on EAST (Experimental Advanced Superconducting Tokamak), the discharges heated with neutral beam injection (NBI) for plasma results in the production of 2.45 MeV deuterium-deuterium (D-D) fusion neutrons. In order to measure the energy spectrum of D-D fusion neutrons, a new Cs 2 7LiYCl6:Ce (CLYC-7) crystal with 7Li-enrichment has been developed and fabricated into a CLYC-7 scintillation detector. Before utilizing this detector for studying neutron energy spectra, it is crucial to explore the response function of the detector within a relevant neutron energy range. Therefore, the detector has been experimented using the 4.5 MeV electrostatic accelerator at Peking University to investigate its response to fast neutrons, energy resolution, and pulse discrimination capability in the neutron energy range 2.07 MeV–5.51 MeV. The neutron reactions occurring within the CLYC-7 scintillator were simulated using MCNPX, focusing on the reactions 35Cl(n,p) and 35Cl(n,α), as well as the energy response curve and the contributions of different particles (protons, alphas) to the neutron spectrum. The experimental results were successfully validated on EAST, where the 2.45 MeV fusion neutron energy spectrum was measured. That demonstrates the ability of the CLYC-7 scintillation detector to diagnose the fusion neutron energy spectrum for deuterium plasma discharge. [ABSTRACT FROM AUTHOR]

Lead-free Cs 3 Cu 2 Cl 5 metal halide exhibits high photoluminescence quantum yield (PLQY), large Stokes shifts and small self-absorption due to self-trapped excitons (STE) emission, which undoubtedly is a potential scintillator material. However, Cs 3 Cu 2 Cl 5 nanocrystals (NCs) are susceptible to degradation by moisture at high humidity environment, which severely affects its long-term application in X-ray imaging. Herein, we prepared Cs 3 Cu 2 Cl 5 scintillator films with a PLQY of 72.4% and a high spatial resolution of 20 lp mm−1. Moreover, we firstly propose a self-healing strategy with facile microwave treatment to recover the crystal structure of Cs 3 Cu 2 Cl 5 film which damaged by moisture, while the photoluminescence (PL) and radioluminescence (RL) intensities of the damaged Cs 3 Cu 2 Cl 5 film are repaired to more than 95% and the spatial resolution can be restored to 20 lp mm−1. Furtherly, the imaging quality of the self-healing scintillator film can be maintained stably by cyclic microwave treatment. It found that microwave treatment provides a simultaneous and molecular level heating environment for the Cs 3 Cu 2 Cl 5 film, which drives the hydrolysates to re-crystallize along with the surface of the destroyed crystals. Therefore, microwave treatment opens a new avenue to recover Cs 3 Cu 2 Cl 5 films degraded by moisture, and provides a solution for long-term application of scintillator films at low cost. [ABSTRACT FROM AUTHOR]

Among the aluminate garnet materials, cerium-doped gadolinium gallium aluminum garnet ceramics (GGAG:Ce) show fast scintillation properties, which suggests that they have promising applications in medical imaging, high-energy ray detection and high-power LED lighting. In this study, Gd 3 Ga 3 Al 2 O 12 :Ce scintillation ceramics co-doped with Me2+ (Me = Mg, Ca) are fabricated using a two-steps route: a solid-state reaction followed by annealing in air. The optical and scintillation properties, including the absorption, radio luminescence (RL), light yield, and decay time, of these co-doped ceramics are studied in detail. Doping with Mg2+ and Ca2+ leads to the oxidation of Ce3+ to Ce4+, which accelerates the scintillation process and decreases the light yield. Co-doping with Ca2+ and Mg2+ shows a synergistic effect on this phenomenon. Compared with 0.2 at% Ca2+ or 0.2 at% Mg2+ single-doped GGAG:Ce, the GGAG:Ce co-doped with 0.1 at% Ca2+ and 0.1 at% Mg2+ has the fastest decay time (∼31 ns) and maintains a relatively high light yield (∼27400 ± 1600 ph/MeV, 77% of undoped GGAG:Ce). These findings shed new light on designing Ce-activated garnet scintillator materials with ultra-fast decay time for applications in time-of-flight (TOF) PET technology. [ABSTRACT FROM AUTHOR]

Recently, novel transparent and fluorescent materials are in demand for various optical applications such as lasers, scintillators, and solid-state lighting. α-SiAlON, which has excellent thermal and mechanical properties, also exhibits photoluminescence depending on the stabilized doped rare-earth ions. Its transparency and fluorescence depend on the rare-earth oxide added as a raw material, particularly in conventional powder processing. In this study, we fabricated α-SiAlON ceramics by adding various rare-earth oxides to elucidate their effects on the transparency and fluorescence of these ceramics. High-transparency α-SiAlON ceramics were fabricated by adding rare-earth oxides whose rare-earth ions have small ionic radii: Y 2 O 3 , Ho 2 O 3 , Er 2 O 3 , Tm 2 O 3 , Yb 2 O 3 , and Lu 2 O 3. Because the fraction of α-SiAlON was high, the relative density was high, and the microstructure was composed of fine grains. In particular, α-SiAlON ceramics prepared by adding Ho 2 O 3 showed lower light scattering than the other fabricated α-SiAlON ceramics because of the smaller α-SiAlON grains, resulting in higher in-line transmittance (48% at 600 nm). Furthermore, these transparent α-SiAlON ceramics exhibited fluorescence corresponding to the activated rare-earth ions: Ho3+, Er3+, Tm3+, and Yb3+ or Yb2+. [ABSTRACT FROM AUTHOR]

The ability of a scintillator to absorb and convert the high-energy X-ray photons to low-energy visible photons is crucial for the application of X-ray in medical tests, security checks and scientific research. However, traditional scintillation crystals are synthesized by complex preparation process with high cost, hindering the wide development in practical applications. Here, Tb3+ doped sodium silicate glass, which exhibits remarkable scintillation property and recoverability to X-ray irradiation, was successfully prepared by an exercisable melt-quenching method. The obtained scintillator shows intense radioluminescence, which is about 1.5 times higher than that of the reference of Bi 4 Ge 3 O 12. The damaged glass to X-ray irradiation can be returned to the original state after heat treatment again, indicating excellent recovery. Moreover, the scintillator displays wonderful thermal stability with the fluorescence intensity at 573 K still remaining 96% at room temperature. These results demonstrate that the obtained scintillating glass has potential application towards the real world. [ABSTRACT FROM AUTHOR]

lthough single crystal scintillators have excellent performance, they have some drawbacks such as high cost, complicated elaboration method and difficulty of growth on large-scale. Glass scintillators are widely investigated to replace single crystal scintillators because of their simple fabrication method and low cost. In this paper, a series of transparent borosilicate aluminate glass scintillators doped with Tb3+ were successfully prepared by traditional melt-quenching method. The structural, luminescent, and X-ray excited scintillating properties were investigated. These glass samples show high stability and high transparency, and present good luminescent and scintillating properties. Sample with Tb3+ doping concentration of 10% has the best scintillating performance. The integrated intensity of X-ray excited luminescence is 66.6% of that of commercial Bi 4 Ge 3 O 12 single crystal scintillator, and the quantum efficiency (under 378 nm excitation) is 70.3%. Our findings suggest that Tb3+-doped borosilicate aluminate glasses with high light yield might be used as potential scintillators. [ABSTRACT FROM AUTHOR]

Recent surge in additive manufacturing efforts demonstrate stereolithography as a promising technique for fabricating glass materials due to the high speed and scalability of the process. However, little efforts have been devoted to manufacture borosilicate glass by the stereolithographic process. One of the challenges is that its relatively low softening temperatures could interfere with the thermal post-printing process and introduce poor fidelity and structure instability. Here, we report on the first demonstration of stereolithographic manufacturing of cerium-doped (Ce-doped) (<10%) and undoped borosilicate glass which was enabled by a multi-step post thermal processing. The optical properties of the printed glass depend on thermal processing parameters (temperature, time, and environment) and can be readily tuned and optimized for a wide range of applications. The printed amorphous glass shows good structural stability with band gap of 3 eV, Urbach energy of 0.75 eV and refractive index of 2.14 for 8% Ce-doped glass, respectively. These results indicate Ce-doped glass fabricated by stereolithography is suitable for scintillator applications and that additive manufacturing could be promising for borosilicate glass fabrication. [ABSTRACT FROM AUTHOR]

Inch-sized Mn-based halide single crystal films, (C 25 H 22 P) 2 MnCl 4 and (C 25 H 22 P) 2 MnBr 4 , with tunable thickness from 0.12 mm to 0.72 mm were designed and used directly in the X-ray imaging. The high light yield of 56,457 and 78,937 photons/MeV and high spatial resolution exceeding 20 lp/mm demonstrates the great potential of large size single crystal scintillator screen for commercial high-resolution X-ray imaging applications. [Display omitted] • Inch-sized Mn-based halide single-crystalline films with tunable thickness from 0.12 mm to 0.72 mm were designed and grown. • The inch-size single crystals of (C 25 H 22 P) 2 MnCl 4 and (C 25 H 22 P) 2 MnBr 4 exhibit high light yield of 56457 and 78937 photons/MeV under X-rays. • The (C 25 H 22 P) 2 MnCl 4 and (C 25 H 22 P) 2 MnBr 4 single crystal screens exhibit outstanding spatial resolution of 21.02 and 25.61 lp/mm. Hybrid metal halides are emerging candidates for X-ray imaging. Due to the poor uniformity, low transmittance and high light scattering of polycrystalline film scintillator screen, resulting in low resolution of X-ray imaging, it is essential a challenging to explore new large-area and single crystal scintillator with high light yield and high resolution. Herein, inch-sized Mn-based halide single crystals, (C 25 H 22 P) 2 MnCl 4 and (C 25 H 22 P) 2 MnBr 4 , with tunable thickness films from 0.12 mm to 0.72 mm were designed and grown. The crystals of (C 25 H 22 P) 2 MnCl 4 and (C 25 H 22 P) 2 MnBr 4 with high photoluminescence quantum yield (PLQY) of 62.42 % and 99.10 % exhibit high light yield of 56,457 and 78,937 photons/MeV under X-ray, which is 1.7 and 2.37 times higher than that of the commercial LYSO scintillator. Both the crystals show high X-ray radiation resistance even exposed to X-ray for 60 mins with a high dose rate of 504 mGy s−1. The high photochemical stability under the continuous UV and X-ray irradiation contributes them towards X‑ray imaging. With such significant merits, the high spatial resolutions about 21.02 and 25.61 lp/mm are achieved on the (C 25 H 22 P) 2 MnCl 4 and (C 25 H 22 P) 2 MnBr 4 single crystal films, which demonstrates the great potential of large size single crystal screen for commercial high-resolution X-ray imaging applications. [ABSTRACT FROM AUTHOR]

Preclinical studies have shown that radiotherapy treatments benefit from ultra-high dose rate (UHDR) irradiations. These trigger the FLASH-effect, resulting in a strong decrease in normal tissue toxicity with conserved tumor control probability, compared with conventional irradiations. However, the beam parameters to trigger the FLASH-effect and the radiobiological mechanisms behind it remain to be elucidated. A limiting factor in many studies is the lack of accurate real time dosimetry. In this work an innovative solution for 2D real time dosimetry in UHDR electron beams is presented and characterized. The in-house developed ImageDosis system consists of a scientific camera, with high temporal resolution, and a coating, containing 12% of Y 3 Al 5 O 12 :Ce 3 + as scintillating material. Reference dosimetry was performed by means of radiochromic film, and a (C 38 H 34 P 2)MnBr 4 point scintillator was used to validate the pulse discrimination properties of the ImageDosis system. Irradiations were performed in two centers (Antwerp and Orsay), with an ElectronFlash accelerator. The ImageDosis system was tested with varying number of pulses, pulse length, pulse repetition frequency (PRF) and energy. In addition, its temporal resolution and 2D properties were investigated. The ImageDosis system showed negligible dose, dose rate and energy dependence for doses up to 13 Gy and average dose rates up to 140 Gy/s, with a dose per pulse up to 2 Gy and a PRF up to 300 Hz. The system is capable of discriminating and measuring the dose of individual pulses and shows promising 2D characteristics that need further optimization. [Display omitted] • The YAG-based ImageDosis system is a promising tool for real time UHDR dosimetry. • The ImageDosis system has shown not to be dose rate dependent. • The ImageDosis system provides 2D characteristics that are relevant for FLASH-RT. • The ImageDosis system has shown not to be energy dependent. • The ImageDosis system is capable of measuring individual pulses. [ABSTRACT FROM AUTHOR]

• 1.0-inch diameter 6LiI:Ag crystals were successfully grown using Bridgman method. • The maximum neutron-gamma PSD figure of merit was obtained to be 1.3. • Energy resolution of the thermal neutron peak of 12.0% can be observed. • 6LiI:Ag is promising neutron detectors in high neutron-gamma mixed fields. This paper discusses crystal growth and characterization of 1.0-inch 6LiI:Ag scintillators for thermal and epithermal neutron detection on the lunar surface as part of the Lunar Vehicle Radiation Dosimeter project. Zone purification method was employed to purify the raw material of 6LiI, and the crystals were grown using the Bridgman method. X-ray luminescence spectrum was measured to confirm the presence of Ag+ in the crystal lattice of 6LiI. The feasibility of neutron detection under 252Cf fast neutron irradiation was investigated. A hydrogen-rich paraffin wax moderator was used to slow down fast neutrons to obtain thermal and epithermal neutrons. The charge comparison method was used to perform pulse shape discrimination. The maximum value of the Figure of Merit was obtained to be 1.3, which demonstrates the capability of using 6LiI:Ag crystal scintillators in high neutron and gamma mixed fields. The energy resolution of the thermal neutron peak varied with the thickness of scintillators, achieving 12.0 % for the 0.5 cm thick samples. The potential for further improvement of the scintillation performance of 6LiI:Ag crystal relies on reducing impurities and color centers. [ABSTRACT FROM AUTHOR]

The ISS-CREAM instrument is the modified version of the Cosmic Ray Energetics And Mass (CREAM) experiment, which was flown on balloons multiple times over Antarctica and later installed on the International Space Station (ISS). Its primary objective is to measure the energy spectra of individual cosmic-ray elements for the charge range of Z = 1 to Z = 26, in the energy range of ∼ 1012 to ∼ 1015 eV. The instrument comprises a tungsten/scintillator calorimeter and a pixelated silicon charge detector as primary detectors to determine the energy and charge of cosmic rays. Additionally, it includes top and bottom scintillator counting detectors and a boronated scintillator detector to differentiate between electrons and hadrons for multi-TeV electron measurements. The ISS-CREAM instrument was installed on the ISS in August 2017 and operated until February 2019. This paper provides an overview of the instrument, focusing on its detectors, trigger systems, common electronics, and power systems. The paper highlights the modifications made to these components to optimize their performance for ISS operations. [ABSTRACT FROM AUTHOR]

This study aims to assess the efficacy of low energy gamma-ray based instrumentation for inspecting the wall thickness of metallic pipes in industrial situations. The primary motivation behind this work is to explore the feasibility of using a Monte Carlo approach, specifically FLUKA simulations, for radiation-based industrial applications. To achieve this objective, laboratory experiments and FLUKA simulations were conducted using 59.5 keV gamma-rays and a NaI(Tl) scintillation detector. The purpose was to detect changes in pipe wall thickness due to erosion and corrosion, enabling timely intervention to prevent any negative consequences. The ability, scoring commands and geometry design of the FLUKA Monte Carlo code were validated in this study by comparing the computed values of gamma-ray scattered/transmitted intensity with experimental data. Regression lines were derived from the computed and experimental data for scattered and transmitted intensity, providing valuable information for pipe wall inspection. The technique exhibited high sensitivity to changes in the wall thickness of metallic pipes, with a detection capability of 1 mm. However, for higher wall thickness, the sensitivity of the low-energy gamma-ray technique decreased due to the influence of overlying scattering/absorption components in the obtained spectra. The maximum sensitivity limit was found to be for a wall thickness of ∼8 mm for metallic pipes. The excellent agreement between simulation results and actual laboratory methods validates FLUKA's high efficacy in checking the condition of industrial pipelines. • Simulations of scattering and transmission measurements for pipe wall thickness. • Validation of FLUKA code with experimental data for pipeline industry. • FLUKA as an alternative to forecast the performance of any new inspection system. • Technique is sensitive enough to detect the thinning (∼1 mm) of metallic wall. [ABSTRACT FROM AUTHOR]

Ce differently (0, 0.01, 0.1, 1, 2 and 5% with respect to Mg) doped LiMgAlF 6 ceramics were synthesized by the spark plasma sintering (SPS) method. In photoluminescence (PL), emission bands appeared at 300 nm with 30 ns day time, and these emission properties were almost the same in scintillation under X-ray irradiation. Further, thermally stimulated luminescence (TSL) was observed after X-ray irradiation, and the primary glow peak temperature was 160 °C with a lower detection limit of ∼10 mGy. • Ce-doped LiMgAlF 6 ceramics were prepared by the spark plasma sintering method. • Photoluminesence and scintillation properties were investigated. • Thermally stimulated luminescence properties were evaluated. [ABSTRACT FROM AUTHOR]

Since their conception in the early 1990s, radioluminescence-based fibre-optic dosimeters (FODs) have attracted great interest for dosimetric applications in radiotherapy (RT). Over the years, many scintillating materials, both organic and inorganic, have been developed and tested by multiple research groups around the world. In parallel, reliable techniques for removing or subtracting the stem effect, one of the main drawbacks of FODs, have been proposed in the literature. To date, several prototype systems are widespread, some of which prove to be viable commercial solutions. This review aims to trace the efforts over the years that have enabled FODs to become reliable tools for dosimetry in the current RT procedures and promising options for future scenarios. After a first section devoted to a thorough discussion of the stem effect issue, the use of FODs in various applications of interest to RT, primarily small-field dosimetry and in vivo dosimetry, are addressed. Their use both in external beam RT, including hadrontherapy, and in brachytherapy are considered. A special focus is given to the peculiarities of MRI LINAC dosimetry and the contributions of FODs in this context. Finally, the state of the art concerning the development and characterization of FODs for monitoring ultra-high dose rate radiation beams, typical of FLASH therapy and microbeam RT are presented, highlighting the challenges still open. • Reliable approaches to face the stem effect issue in FODs are available. • The small sensitive volumes of FODs make them attractive for small-field dosimetry and in-vivo dosimetry. • One major issue of FODs dosimetry in hadrontherapy is the LET dependence. • Several evidences support that FODs are accurate for MRI-LINACs dosimetry. • Various studies highlight the pros and cons of FODs in ultra-high dose rate irradiations. [ABSTRACT FROM AUTHOR]

In fibers made from organic plastic scintillators, a combination of extrinsic and intrinsic effects results in the attenuation of light and thus in a position-dependent light yield. The trapping of photons can further be affected if fibers are coated with or wrapped in a light-absorbing or reflecting material to suppress optical cross-talk. These effects have frequently been studied for long (> 0. 5 m) fibers, yet little data is available for shorter ones. We experimentally studied the position-dependent light yield of single-cladded Kuraray SCSF-78 fibers with lengths of < 10 cm and tested the effect of different cross-talk-preventing materials. Contrary to the often acceptable simplification that light is transmitted in the fiber core alone, we found that photons trapped by the protective cladding significantly contribute to the light transmission in short fibers. In this paper, we perform an in-depth characterization of the position-dependent light yield of fibers sputter-coated with aluminum and wrapped in aluminum foil using a double-exponential attenuation function. Finally, we compare our findings to a simple photon transport model. • Attenuation results in a position-dependent light yield in scintillating fibers. • Coating or wrapping fibers to prevent optical cross-talk changes attenuation. • Light yield in short scintillating fibers is strongly position-dependent. • Photon transport in the fiber cladding contributes significantly to light yield. • Sputter-coating with aluminum is best and easiest method for cross-talk prevention. [ABSTRACT FROM AUTHOR]

The Jiangmen Underground Neutrino Observatory (JUNO) is a 20 kt low level radioactivity liquid scintillator detector in a laboratory 650 m underground. An excellent energy resolution and a large volume offer exciting opportunities for addressing many important topics in neutrino physics. High purity nitrogen is an important factor to ensure the low background of the JUNO detector. High Purity Nitrogen (HPN) is used for detector purging, pipe cleaning, and scintillator purification, among other things in JUNO. According to JUNO's requirements, the radon concentration in HPN should be less than 10 μ Bq/m3. To meet this requirement, A high-purity nitrogen plant with 100 Nm3/h maximum rate was designed and constructed. Low-temperature adsorption technology is used to remove radioactive impurities in nitrogen. High purification efficiency was ensured by using an activated carbon column with high column height-to-diameter ratio. Electrostatic collection and low-temperature enrichment methods are combined to measure radon in nitrogen. After ten days of continuous operation at 50 Nm3/h flux rate, the plant can to reduce the radon concentration in nitrogen from 37. 4 ± 1. 8 μ Bq/m3 to less than 1.33 μ Bq/m3. After HPN with flow rate of 50 Nm3/h passing through low-background pipeline (About 1.3 km), the radon concentration of HPN is 5. 6 ± 0. 6 μ Bq/m3. • The high purity nitrogen plant with maximum flow rate of 100 Nm3/h was constructed. • The radon concentration in HPN radon is lower than 1.33 uBq/m3 after 10 days of continuous running of HPN plant. HPN with design flow rate of 50 Nm3/h after passing through low-background pipeline (about 1.3km),the radon concentration of HPN is 5.5 ± 0.6 uBq/m3, which meets JUNO requirements in the underground. [ABSTRACT FROM AUTHOR]

The photoluminescence and scintillation properties of n-bromophenethylammonium lead chloride ((n-BrPEA) 2 PbCl 4) (n = 4, 3, and 2) and phenethylammonium lead chloride ((PEA) 2 PbCl 4) have been investigated. All the samples showed broad emission peaks at 400–700 nm upon excitation by UV light or X-ray. The decay time constants of 8–28 ns were obtained which originated from the recombination of self-trapped exciton (STE) within inorganic layers. The afterglow levels at 20 ms after 2 ms of X-ray irradiation of (4-BrPEA) 2 PbCl 4 and (3-BrPEA) 2 PbCl 4 (76 and 55 ppm) were better than (PEA) 2 PbCl 4 (379 ppm). The light yield of (4-BrPEA) 2 PbCl 4 (3100 photons/5.5 MeV-α) was higher than (PEA) 2 PbCl 4 (1400 photons/5.5 MeV-α). • (BrC 6 H 4 C 2 H 4 NH 3) 2 PbCl 4 crystals were grown by the slow cooling method. • All the crystals showed the luminescence due to the recombination of the self-trapped excitons confined in inorganic layers. • The (4-BrC 6 H 4 C 2 H 4 NH 3) 2 PbCl 4 crystal showed the highest QY in the present crystals. • The light yields of the (4-BrC 6 H 4 C 2 H 4 NH 3) 2 PbCl 4 crystals surpassed that of the unsubstituted crystal. [ABSTRACT FROM AUTHOR]