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The zero-dimensional copper halide perovskite Cs 3 Cu 2 I 5 displays extraordinary luminescence and scintillation characteristics, and high-quality crystals are extremely desirable for exploring the commercial applications. Currently, the most critical issue in the solution growth of Cs 3 Cu 2 I 5 crystals is the easy oxidation of halides, which significantly hinders the optimization of crystal qualities. The hypophosphorous acid (H 3 PO 2) has been applied to inhibit the oxidation, nevertheless, the related mechanism is elusive and has been largely ignored. Herein, Cs 3 Cu 2 I 5 crystals have been grown from N, N-Dimethylformamide (DMF) solvent by the antisolvent vapor-assisted crystallization (AVC) method. It is verified that H 3 PO 2 effectively prevents the oxidation of Cs 3 Cu 2 I 5 by rapidly reducing Cu2+ and I 3 −, maintaining the stability of the precursor solution and continuously suppressing oxidation during the whole growth process. Meanwhile, by increasing the acidity of the solution, H 3 PO 2 dissolve precursor colloids and efficiently enhance the solubility of halides. Thus, the addition of H 3 PO 2 favors the rapid growth of centimeter-sized Cs 3 Cu 2 I 5 crystals with well-defined crystallographic planes within several days. As excellent gamma ray scintillator, the crystal exhibits high light yield of 38000 photons/MeV, with energy resolution of 5.6 % under 662 keV radiation from a 137Cs source. This work deeply elucidates new insight into the critical effect of H 3 PO 2 in the DMF based solution crystal growth, facilitating the preparation of large-size and high-performance copper halide perovskite crystals. [ABSTRACT FROM AUTHOR]

A plastic scintillator has found extensive application in the realm of high-energy physics and national security science. Many applications in those fields often involve the simultaneous production of photons, neutrons, and charged particles, which makes the relative sensitivity information for these different radiation types important. In this study, we have adopted a multi-head detector comprised of a plastic scintillator and high gain phototubes, which provides a large dynamic range and linearity. A comparative study on the relative sensitivities of plastic scintillators was facilitated by adopting three distinct radiation calibration sources (i.e., 60Co γ rays, DD neutrons, and DT neutrons). Neutrons from a DD source generate a comparable level of scintillation to gamma rays emitted by 60Co (i.e., 60Co-γ/DD-n = 0.92 ± 16%). DT neutrons induce ∼3.5 times the scintillation observed with DD neutrons (i.e., DT-n/DD-n = 3.5 ± 28%). In addition, the Geant4 simulation granted us valuable insights into the relative sensitivity of the scintillator. This comparative study will provide a useful database for users in diverse applications. [ABSTRACT FROM AUTHOR]

Silicon photomultipliers (SiPMs) are solid-state single-photon-sensitive detectors that show excellent performance in a wide range of applications. In FBK (Trento, Italy), we developed a position-sensitive SiPM technology, called "linearly graded" (LG-SiPM), which is based on an avalanche-current weighted-partitioning approach. It shows position reconstruction resolution below 250 μm on an 8 × 8 mm2 device area with four readout channels and minimal distortions. A recent development in terms of LG-SIPM is a larger chip version (10 × 10 mm2) based on FBK NUV-HD technology (near-ultraviolet sensitive), with a peak photon detection efficiency at 420 nm. Such a large-area detector with position sensitivity is very interesting in applications like MR-compatible PET, high-energy physics experiments, and readout of time-projection chambers, gamma and beta cameras, or scintillating fibers, with a reduced number of channels. These SiPMs were characterized in terms of noise, photon detection efficiency, and position resolution. We also developed tiles of 2 × 2 and 3 × 3 LG-SiPMs, reaching very large sensitive areas of 20 × 20 mm2 and 30 × 30 mm2. We implemented a "smart-channel" configuration, which allowed us to have just six output channels for the 2 × 2 elements and eight channels for the 3 × 3 element tiles, preserving a position resolution below 0.5 mm. These kinds of detectors provide a great advantage in compact and low-power applications by maintaining position sensitivity over large areas with a small number of channels. [ABSTRACT FROM AUTHOR]

The reduction in the effective dose of evacuated injured persons through contaminated areas of nuclear accidents is an essential emergency services requirement. In this context, there appeared a need to develop a dose-optimised route finding method for firefighting rescue vehicles, which includes the development of a real-time decision support measurement and evaluation system. This determines and visualises the radiation exposure of possible routes in a tested area. The system inside and outside of the vehicle measures the ambient dose equivalent rate, the gamma spectra, and also the airborne radioactive aerosol and iodine levels. The method uses gamma radiation measuring NaI(Tl) scintillation detectors mounted on the outside of the vehicle, to determine the dose rate inside the vehicle using the previously recorded attenuation conversation function, while continuously collecting the air through a filter and using an alpha, beta, and gamma radiation measuring NaI(Tl)+ PVT + ZnS(Ag) scintillator to determine the activity concentration in the air, using these measured values to determine the effective dose for all routes and all kinds of vehicles. The energy-dependent shielding effect of the vehicle, the filtering efficiency of the collective protection equipment, and the vehicle's speed and travel time were taken into account. The results were validated by using gamma point sources with different activity and energy levels. The measurement results under real conditions and available real accident data used in our simulations for three different vehicles and pedestrians proved the applicability of the system. During a nuclear accident based on our model calculations, the inhalation of radioactive aerosols causes a dose almost an order of magnitude higher than the external gamma radiation caused by the fallout contamination. The selection of the appropriate vehicle and its route is determined by the spectrum that can be measured at the accident site but especially by the radioactive aerosol concentration in the air that can be measured in the area. In the case of radiation measuring detectors, the shielding effect of the carrier vehicle must be taken into account, especially in the case of heavy shielding vehicles. The method provides an excellent opportunity to reduce the damage to the health of accident victims and first responders during rescue operations. [ABSTRACT FROM AUTHOR]

In this study, the interaction parameters of neutrons, charge particles and gamma rays in seven inorganic scintillation materials with densities ranged from 3.86 to 8.30 g/cm3 were theoretically examined. SRIM Monte Carlo software was used to determine the range of $ {H^ + },H{e^{ + + }},A{u^ + }and\textrm{ }\,{O^{ - - }} $ H + , H e + + , A u + and O − − ions in the energy range (0.01–20) MeV, Phy-X/PSD while Py-MLBUF computer programs were used to estimate gamma radiation interaction parameters in the energy range (0.02–15) MeV. The electron total stopping power and range values at energies ranging from 0.01 to 1000 MeV were calculated using the ESTAR NIST program. The fast neutron removal cross-section (FNRCS) and the macroscopic effective removal cross-section (MRCS) were calculated using the Phy-X/PSD and MRCS tools, respectively. The outcomes of this research showed that the range of $ {H^ + },H{e^{ + + }},A{u^ + }and\textrm{ }\,{O^{ - - }} $ H + , H e + + , A u + and O − − ions increased with decreasing sample density but decreased with increasing projectile energies; the largest range of $ {H^ + } $ H + is 2090 µm in the lowest density S1 sample, while the range of $ \textrm{ }A{u^ + } $ A u + is 5.16 µm in the same sample. The denser sample S7 had the highest stopping power and the lowest range at higher electron energies. The S1 sample had the highest calculated HVL value of 5.403 cm, while the S7 sample had the lowest calculated HVL value of 0.0008 cm. Rising sample density causes the MAC to rise, while rising gamma energy causes the MAC to decrease. The highest MAC value recorded was 107 cm2/g at 0.015 MeV in the S7 sample, and the lowest value recorded was 0.0369 cm2/g at 15 MeV in the S1 sample. For all inorganic scintillation samples at particular gamma energies, the standard deviations for the MAC, HVL and Zeff values between the Phy-X/PSD and, Py-MLBUF programs were calculated. With energy range variation, the results for Zeff for the two samples S2 and S4 appeared to be constant. Regards to the fast neutrons, the heights value's of FNRCS, and MRCS were recorded for S7. [ABSTRACT FROM AUTHOR]

Angular resolution is crucial for the detailed study of gamma-ray sources and current Cherenkov telescopes (e.g., HESS, MAGIC, and VERITAS) that operate below tens of TeV. Several gamma-ray sources with a photon energy larger than 100 TeV have been revealed by the LHAASO in recent years; the angular resolution of the LHAASO is around  0.3 ∘ . A gamma-ray detector with an angular resolution of less than  0.1 ∘  operating beyond 100 TeV is needed to study the detailed morphology of ultra-high-energy gamma-ray sources further. The cost-effectiveness is crucial for such large-area detectors. In this paper, the impact of telescope aperture, field of view, pixel size, optical point spread function, and signal integration time window on angular resolution is studied. These results can provide essential elements for the design of telescope arrays. [ABSTRACT FROM AUTHOR]

Background: Evaluation of the boron dose is essential for boron neutron capture therapy (BNCT). Nevertheless, a direct evaluation method for the boron‐dose distribution has not yet been established in the clinical BNCT field. To date, even in quality assurance (QA) measurements, the boron dose has been indirectly evaluated from the thermal neutron flux measured using the activation method with gold foil or wire and an assumed boron concentration in the QA procedure. Recently, we successfully conducted optical imaging of the boron‐dose distribution using a cooled charge‐coupled device (CCD) camera and a boron‐added liquid scintillator at the E‐3 port facility of the Kyoto University Research Reactor (KUR), which supplies an almost pure thermal neutron beam with very low gamma‐ray contamination. However, in a clinical accelerator‐based BNCT facility, there is a concern that the boron‐dose distribution may not be accurately extracted because the unwanted luminescence intensity, which is irrelevant to the boron dose is expected to increase owing to the contamination of fast neutrons and gamma rays. Purpose: The purpose of this research was to study the validity of a newly proposed method using a boron‐added liquid scintillator and a cooled CCD camera to directly observe the boron‐dose distribution in a clinical accelerator‐based BNCT field. Method: A liquid scintillator phantom with 10B was prepared by filling a small quartz glass container with a commercial liquid scintillator and boron‐containing material (trimethyl borate); its natural boron concentration was 1 wt%. Luminescence images of the boron‐neutron capture reaction were obtained in a water tank at several different depths using a CCD camera. The contribution of background luminescence, mainly due to gamma rays, was removed by subtracting the luminescence images obtained using another sole liquid scintillator phantom (natural boron concentration of 0 wt%) at each corresponding depth, and a depth profile of the boron dose with several discrete points was obtained. The obtained depth profile was compared with that of calculated boron dose, and those of thermal neutron flux which were experimentally measured or calculated using a Monte Carlo code. Results: The depth profile evaluated from the subtracted images indicated reasonable agreement with the calculated boron‐dose profile and thermal neutron flux profiles, except for the shallow region. This discrepancy is thought to be due to the contribution of light reflected from the tank wall. The simulation results also demonstrated that the thermal neutron flux would be severely perturbed by the 10B‐containing phantom if a relatively larger container was used to evaluate a wide range of boron‐dose distributions in a single shot. This indicates a trade‐off between the luminescence intensity of the 10B‐added phantom and its perturbation effect on the thermal neutron flux. Conclusions: Although a partial discrepancy was observed, the validity of the newly proposed boron‐dose evaluation method using liquid‐scintillator phantoms with and without 10B was experimentally confirmed in the neutron field of an accelerator‐based clinical BNCT facility. However, this study has some limitations, including the trade‐off problem stated above. Therefore, further studies are required to address these limitations. [ABSTRACT FROM AUTHOR]

Core to advancing time‐of‐flight positron emission tomography (ToF‐PET) toward a less invasive, more flexible procedure with a higher diagnostic power is the development of enhanced radiation detector materials. One promising avenue is the development of heterostructured scintillators where multiple materials work in synergy to exceed the performance of each individual component. Applied to ToF‐PET detectors, one component contributes predominantly to the absorption of gamma rays and the other to the creation of ultra‐fast photons. Whilst other authors have proposed various concepts, heterostructured scintillators are still in their infancy and scientifically guiding their development remains a challenge. Toward this aim and based on simulation and modeling developments, heterostructure properties are directly linked to ToF‐PET performance. This is made possible by redefining the notions of detector photo‐peak efficiency and timing response, as defined for monolithic detectors, in the context of heterostructured scintillators. Their overall potential is then discussed as a function of the materials and design used. This provides a quantitative framework to rapidly and efficiently support the advancement of heterostructured detectors for ToF‐PET technology. [ABSTRACT FROM AUTHOR]

POLAR-2, a plastic scintillator based Compton polarimeter, is currently under development and planned for a launch to the China Space Station in 2025. It is intended to shed a new light on our understanding of Gamma-Ray Bursts by performing high precision polarization measurements of their prompt emission. The instrument will be orbiting at an average altitude of 383 km with an inclination of 42° and will be subject to background radiation from cosmic rays and solar events. In this work, we tested the performance of plastic scintillation bars, EJ-200 and EJ-248M from Eljen Technology, under space-like conditions, that were chosen as possible candidates for POLAR-2. Both scintillator types were irradiated with 58 MeV protons at several doses from 1.89 Gy(corresponding to about 13 years in space for POLAR-2) up to 18.7 Gy, that goes far beyond the expected POLAR-2 life time. Their respective properties, expressed in terms of light yield, emission and absorption spectra, and activation analysis due to proton irradiation are discussed. Scintillators activation analyses showed a dominant contribution of β + decay with a typical for this process gamma-ray energy line of 511 keV. [ABSTRACT FROM AUTHOR]

Nano-glasses are next-generation scintillators combining favorably the merits of both scintillator crystals and glasses. Here, a new nano-glass scintillator is prepared embedding CsGd 2 F 7 :Ce3+ nanocrystals (NCs). The microscopic morphology, particle size, and distribution of the NCs are studied by high resolution transmission electron microscopy. Significantly enhanced radioluminescence efficiency is obtained in the nano-glasses. The largest integrable intensity of X-ray excited luminescence is 316% of the standard Bi 4 Ge 3 O 12 (BGO) crystal. A well-resolved full-energy peak with an energy resolution of 17.4% is registered for the 662 keV gamma rays, and the light yield is determined to be 827 ± 8 ph/MeV. The nano-glass scintillators exhibit good radiation hardness and thermal stability. As a proof of concept, an X-ray imaging system of a good resolution is built on the nano-glass scintillators. [ABSTRACT FROM AUTHOR]

The research aims to study the primary interaction between gamma radiation in CeBr3 crystal. The analysis of mass attenuation coefficient (MAC), effective atomic number (Zeff), electron density (Neff), mean free path (MFP), and energy absorption buildup factor (EABF) was evaluated using the using the WinXCom software. Also, the interaction with charged particles as the total mass stopping power (TMSP), projected range (PR) of proton ( H 1 1 ) and alpha ( H 2 4 e ) particles were evaluated by SRIM programming. The results found that the MAC depends on the energy ranges, the photoelectric effect is the main interaction at low energy ranges, Compton scattering phenomena illustrate and evidents at intermediate energy ranges, and pair production characteristics dominate over on 1.022 MeV in high energy ranges. Moreover, absorption edges appear on energy's discontinuity at low energy. The Zeff and Neff show similar trends and correspond to the energy ranges. The MFP of the CeBr3 compared with some standard scintillators such as NaI and BGO crystal and found that the BGO responds to faster interaction than CeBr3 and NaI crystals. The EABF shows scattering energies followed by atomic equivalent (Zeq), and they also increase with increasing penetration depth (mfp). The TMSP and PR depend on charged particles, density, and the unit path distance of a material. [ABSTRACT FROM AUTHOR]

Organic liquid scintillation detectors are widely used to measure the presence of radiation. With these devices, there are advantages in that they are easy to manufacture, large in size, and have a short fluorescence decay time. However, they are not suitable for gamma spectroscopy because they are composed of a low-atomic-number material. In this regard, alternative materials for the secondary solute used in basic organic liquid scintillators have been investigated, and the applicability of alternative materials, the detection characteristics, and neutron/gamma identification tests were all assessed. 7-Diethylamino-4-methylcoumarin (DMC), selected as an alternative material, is a benzopyrone derivative in the form of colorless crystals with high fluorescence, a high quantum yield in the visible region, and excellent light stability. In addition, it has a large Stokes shift, and solubility in a solvent is good. Through an analysis in this study, it was found that the absorption wavelength range of DMC coincides with the emission wavelength range of PPO, which is the primary solute used with DMC. Finally, it was confirmed that the optimal concentration of DMC was 0.08 wt%. As a result of performing gamma and neutron measurement tests using a DMC-based liquid scintillator, it was found to perform well (FOM = 1.42) compared to a commercial liquid scintillator, BC-501A. [ABSTRACT FROM AUTHOR]

Zero‐dimensional (0D) structure‐based manganese metal halides (MHs) are believed to be the most promising candidates for the next‐generation X‐ray scintillators due to their intense radioluminescence and environmental friendliness. However, low‐temperature (<180 °C), large‐area integration with more efficient X‐ray detection remains a tremendous challenge. Herein, from the perspective of cation (ionic liquids) structure design, the basic physical parameters of 0D MHs are regulated. And the calculations and experimental results demonstrate larger‐size cations that induce lower melting temperatures, larger exciton‐binding energies, larger ion migration energy, and tunable hardness, which are most desirable for MHscintillators. As a result, the champion materialHTP2MnBr4is achieved as glassy transparency wafer by low‐temperature (165 °C) melt‐quenching. Its application to X‐ray imaging features high spatial resolution (17.28 lp mm−1), scalability (>30 × 30 cm2), and integration with strong coupling force. Furthermore, HTP2MnBr4 glass with reproducible properties demonstrates a high light yield (38 000 photon MeV−1), excellent irradiation stability, and low detection limit (0.13 µGy s−1). The authors believe this work will provide guidance for MHscintillators to further commercial applications. [ABSTRACT FROM AUTHOR]

In recent years, with the further study of rare earth halide scintillation crystals, many excellent properties of these materials have been discovered, especially the neutron/gamma ray dual detection performance, which has attracted much attention. Ce doped lithium based elpasolite scintillation crystal with chemical composition of A2LiRX6: Ce (A, R, X represent + 1 valence metal element, rare earth element, halogen element respectively) and Eu doped lithium based alkaline earth metal halide with chemical composition of LiM2X5: Eu (M, X represent + 2 valence metal element, halogen element respectively) are considered to be very practical and potential dual detection materials. They can detect neutrons and gamma rays simultaneously, and most of them have high light output, excellent energy resolution and other characteristics. At present, as the most representative of Ce doped lithium based elpasolite scintillation crystal, Cs2LiYCl6:Ce (CLYC) has been widely studied and produced. However, Eu doped lithium based alkaline earth metal halide, which is expected to replace elpasolite scintillation crystal materials such as CLYC, is rarely reported. In this paper, the research progress of the above two kinds of dual-mode detection materials is briefly reviewed, with a view to enlightening researchers in related fields. [ABSTRACT FROM AUTHOR]

Single-crystalline films (SCFs) of the LuAG: Ce garnet grown using the liquid-phase epitaxy method onto YAG single-crystal (SC) substrates were investigated for possible applications as composite thermoluminescent (TL) detectors. Such detectors may help to register the different components of ionizing radiation fields with various penetration depths, e.g., heavy charged particles and gamma or beta rays. It was found that the TL signal of LuAG: Ce SCF sufficiently differs from that of the YAG substrate concerning both the temperature and wavelength of emissions. Furthermore, even by analyzing TL glow curves, it was possible to distinguish the difference between weakly and deeply penetrating types of radiation. Within a test involving the exposure of detectors with the mixed alpha/beta radiations, the doses of both components were determined with an accuracy of a few percent. [ABSTRACT FROM AUTHOR]

A new broad-energy, high-resolution gamma ray spectrometer (GRS) with Compton suppression function has been developed recently in the HL-2A tokamak to obtain the gamma ray information in the energy range of 0.1–10 MeV. This is the first time to develop an anti-Compton GRS for a magnetic confinement fusion device. The anticoincidence detector consists of a large-volume high purity germanium (HPGe) crystal (Φ63 × 63 mm2) as the primary detector and eight trapezoidal bismuth germinate (BGO) scintillators (trapezoid crystal with 30 mm thickness) as the secondary detector. The anti-coincidence data processing is implemented by a digital-based data acquisition system with fast digitization and software signal processing technology. Using radioisotope gamma ray sources and Monte Carlo N-Particle code, the energy and efficiency of the spectrometer have been calibrated and quantitatively tested. The Compton continuum suppression factor reaches 4.2, and the energy resolution (Full Width at Half Maximum) of the 1.332 MeV full energy peak for 60Co is 2.1 keV. Measurements of gamma ray spectra with Compton suppression using the spectrometer have been successfully performed during HL-2A discharges with different conditions. The performance of the spectrometer and the first experimental results are presented in this paper. [ABSTRACT FROM AUTHOR]

The crystals of (Lu,Gd)3(Ga,Al)5O12 multicomponent garnets with high density ρ and effective atomic number Zeff are characterized by high scintillation efficiency and a light yield value up to 50,000 ph/MeV. During recent years, single-crystalline films and composite film/crystal scintillators were developed on the basis of these multicomponent garnets. These film/crystal composites are potentially applicable for particle identification by pulse shape discrimination due to the fact that α-particles excite only the film response, γ-radiation excites only the substrate response, and β-particles excite both to some extent. Here, we present new results regarding scintillating properties of selected (Lu,Gd)3(Ga,Al)5O12:Ce single-crystalline films under excitation by alpha and beta particles and gamma ray photons. We conclude that some of studied compositions are indeed suitable for testing in the proposed application, most notably Lu1.5Gd1.5Al3Ga2O12:Ce film on the GAGG:Ce substrate, exhibiting an α-particle-excited light yield of 1790–2720 ph/MeV and significantly different decay curves excited by α- and γ-radiation. [ABSTRACT FROM AUTHOR]

We present the Large Imaging Spectrometer for Solar Accelerated Nuclei (LISSAN), a new solar dedicated satellite instrument concept. LISSAN relies on an indirect Fourier imaging technique valid over an energy range from 40 keV up to 100 MeV. Spatial information is encoded into 15 moiré patterns by 15 pairs of slightly offset grids (bigrids) separated by a fixed distance enabling a predicted spatial resolution of 10". The time, location, and energy of each incoming photon is recorded via a pixelated gadolinium aluminium gallium garnet (GAGG) crystal scintillator detector placed in alignment with each bigrid, therefore providing simultaneous imaging and spectroscopy from the same imaging system. X-ray and gamma-ray emission are key diagnostics of electron and ion acceleration, respectively. However, despite being a fundamental process that occurs throughout the Universe, particularly in the solar atmosphere, only one resolved gamma-ray image of ion acceleration in a solar flare has ever been achieved. LISSAN will shed new light on this process by providing spectral resolution better than 1.5% FWHM at 6.1 MeV, an imaging effective area at 2.2 MeV of 100 cm2 (more than 25 times greater than past missions such as RHESSI) and a 10 s cadence. Thanks to these significant advances over the previous satellite-based solar detectors, LISSAN will provide reliable imaging and the spectral characterization of both electron and ion acceleration in solar eruptive events simultaneously for the first time, enabling to it to answer several important open questions regarding solar particle acceleration and the initiation of space weather events. [ABSTRACT FROM AUTHOR]

Fast neutron active interrogation is a powerful method for detecting shielded contraband, including explosives, narcotics, and special nuclear material. Pulsed neutron sources can produce intense, time-dependent gamma-ray signatures of contraband, but the detection of those gamma rays is frequently challenging due to high detector pileup. Organic scintillators are fast and cost-effective gamma-ray detectors and thus could be well suited for this application if they can provide adequate gamma-ray spectroscopy. We discuss the use of maximum likelihood estimation maximization based spectral reconstruction techniques for organic scintillators to reconstruct the inelastic scattering and capture gamma-ray spectra produced in neutron active interrogation. Several contraband simulants were irradiated with a pulsed deuterium-tritium neutron generator, and organic liquid scintillators were used to record the emitted radiation signatures. The gamma-ray spectra are time-gated based on the measured neutron pulse time profile, which is shown to be able to improve the signal-to-background ratio for contraband gamma-ray signatures. We isolated several major gamma-ray signatures in the reconstructed spectra that correspond to contraband constituent elements, allowing for the identification of potential contraband objects. We additionally show that the reconstructed gamma-ray spectra can be used to measure sample stoichiometry and discriminate benign from contraband simulant objects. [ABSTRACT FROM AUTHOR]

Waseda University and Tokyo Tech are developing a 50 kg-class small satellite, tentatively named INnovative Space Probe for Imaging R-process Emission (I N S P I R E), which is scheduled for launch in 2027. The primary detector of the satellite is a BOX-type Compton Camera (CC-Box) that enables to observe low energy gamma rays (30 keV − 200 keV) in pinhole mode and high energy gamma rays (150 keV − 3 MeV) in Compton mode. The CC-Box consists of a pixelized Ce:GAGG scintillator array using a depth-of-interaction (DOI) structure, which is optically coupled to an MPPC array. The Ce:GAGG arrays are also positioned on the side of detector to enhance its sensitivity. Herein, we describe the detailed design of the CC-Box, its data processing flow, and its weight and power specifications. We then assess the anticipated performance of the detector in terms of continuum and line sensitivities, together with a simulation of the Crab nebula observation. Finally, a brief review of the experimental results is performed using hands-on devices already implemented in nuclear medicine and atmospheric observations, such as gamma-ray imaging of thunderclouds. [ABSTRACT FROM AUTHOR]

In nuclear power plants, particle accelerators, and other nuclear facilities, measuring the level of ionising gamma radiation is critical for the safety and management of the operation and the environment's protection. However, in many cases, it is impossible to monitor ionising radiation directly at the required location continuously. This is typically either due to the lack of space to accommodate the entire dosimeter or in environments with high ionising radiation activity, electromagnetic radiation, and temperature, which significantly shorten electronics' lifetime. To allow for radiation measurement in such scenarios, we designed a fibre optic dosimeter that introduces an optical fibre link to deliver the scintillation radiation between the ionising radiation sensor and the detectors. The sensors can thus be placed in space-constrained and electronically hostile locations. We used silica optical fibres that withstand high radiation doses, high temperatures, and electromagnetic interference. We use a single photon counter and a photomultiplier to detect the transmitted scintillation radiation. We have shown that selected optical fibres, combined with different scintillation materials, are suitable for measuring gamma radiation levels in hundreds of kBq. We present the architecture of the dosimeter and its experimental characterisation with several combinations of optical fibres, detectors, and scintillation crystals. [ABSTRACT FROM AUTHOR]

In the present article, the influence of the activator concentration and impurity content of raw materials on the luminescence and scintillation properties of Li2CaSiO4 was studied. Polycrystalline powder material was obtained by the sol–gel method. It was shown that europium had limited solubility in the host lattice with a limiting concentration proximate to 0.014 formula units. The maximum intensity of photoluminescence was observed with a divalent europium concentration of 0.002 formula units; the light yield under alpha-particle excitation was measured to be 21,600 photons/MeV for ~200 μm of coating, and under neutron excitation, it was calculated to be 103,800 photons/n, the scintillation kinetics was characterized by an effective decay time of 157 ns. These properties and the transparency in the visible spectrum make it possible to produce scintillation screens with a coating of Li2CaSiO4 for detecting neutrons, alpha particles and low-energy beta radiation. The low Zeff (~15) of this compound makes it less sensitive to gamma rays. The 480 nm blue emission peak makes this material compatible with most commercial PMT photocathodes, CCD cameras and silicon photomultipliers, which have a maximum quantum efficiency in the blue–green spectral region. [ABSTRACT FROM AUTHOR]

We implemented a didactic experiment to study the angular correlation between the two gamma rays emitted in typical 60Co radioactive decays. We used two NaI(Tl) scintillators, already available in our laboratory, and a low-activity 60Co source. The detectors were mounted on two rails, with the source at their center. The first rail was fixed, while the second could be rotated around the source. We performed several measurements by changing the angle between the two scintillators in the range from 90° to 180°. Dedicated background runs were also performed, removing the source from the experimental setup. We found that the signal rate increases with the angular separation between the two scintillators, with small discrepancies from the theoretical expectations. [ABSTRACT FROM AUTHOR]

NaI(Tl) scintillators can detect thermal neutrons with surprising efficiency, even in the presence of ambient gamma radiation. This is due to a peculiarity of the 128I level scheme. Deexcitation cascades following neutron captures in 127I, a main constituent of NaI with quite large neutron capture cross section, unexpectedly often involve the 167.4 keV state of 128I with 175 ns half-life, which feeds another isomeric level at 137.9 keV having a half-life of 845 ns. The 29.5 keV transition between both levels, as well as the subsequent deexcitation sequence to ground state comprising 137.9 keV sum energy, are almost certainly absorbed in the crystal. Signals including three scintillation pulses within few microseconds, the first one caused by a prompt part of the cascade, the second and third one disclosing 30 and 138 keV energy depositions and characteristic delays, are clearly related to such neutron captures. Double-pulse sequences comprising only the primary pulse and a delayed 138 keV signal are also distinctive but more prone to load-dependent background by random pulse pileups. This article demonstrates neutron detection with a Ø2” $\times2$ ” NaI(Tl) scintillation detector by finding and analyzing such double- and triple-pulse sequences in digitized detector signals. It quantifies effect and background rates as a function of the detector load ranging up to 30 kcps. Complementary measurements with a 6Li codoped Ø2” $\times2$ ” NaI(Tl) (NaIL) scintillator allow relating the neutron detection yield by delayed-coincidence counting to the 6Li capture rate in the same crystal and thus to evaluate prospects and limits of this technique. [ABSTRACT FROM AUTHOR]

The CALorimetric Electron Telescope (CALET) on the International Space Station consists of a high-energy cosmic-ray CALorimeter (CAL) and a lower-energy CALET Gamma-ray Burst Monitor (CGBM). CAL is sensitive to electrons up to 20 TeV, cosmic-ray nuclei from Z = 1 through Z ∼ 40, and gamma rays over the range 1 GeVâ€"10 TeV. CGBM observes gamma rays from 7 keV to 20 MeV. The combined CAL-CGBM instrument has conducted a search for gamma-ray bursts (GRBs) since 2015 October. We report here on the results of a search for X-ray/gamma-ray counterparts to gravitational-wave events reported during the LIGO/Virgo observing run O3. No events have been detected that pass all acceptance criteria. We describe the components, performance, and triggering algorithms of the CGBMâ€"the two Hard X-ray Monitors consisting of LaBr3(Ce) scintillators sensitive to 7 keVâ€"1 MeV gamma rays and a Soft Gamma-ray Monitor BGO scintillator sensitive to 40 keVâ€"20 MeVâ€"and the high-energy CAL consisting of a charge detection module, imaging calorimeter, and the fully active total absorption calorimeter. The analysis procedure is described and upper limits to the time-averaged fluxes are presented. [ABSTRACT FROM AUTHOR]

Plastic scintillators (PS) allow design of portative lightweight devices for quantification of low‐activity radiation sources. We have recently suggested a new type of organic fluorophores based on triphenyl pyrazoline (PZ) derivatives with high fluorescence quantum yield showing high radioluminescence when combined with a polyvinyltoluene (PVT) matrix. In this publication we report on radioluminescence properties of the PZ−X family with various halogen substitution (X=F, Cl, Br, I), or having vinyl functional group (vPZ, X=vinyl). PS based on such fluorophores and PVT matrix can be prepared as bulk samples, micrometer size beads or cladding on optical fibers. Application of fluorophores with vinyl functional groups enabled their enhanced interaction with the matrix due to covalent bonding between the components. We demonstrate high performance of PZ−X fluorophores and especially vPZ fluorophore in fabrication of nanocomposites for detection of various types of radiation. Scintillators have enhanced gamma ray detection capabilities with an addition of triphenyl Bi, or Gd2O3 nanoparticles. High fluorescence quantum yield and luminosity of PZ fluorophores allows dramatical reduction of their content in PS systems. Mechanisms of energy transfer and conversion during scintillation process are discussed. Special consideration is given to enhancement of α/β and neutron/gamma (n/γ) pulse shape discrimination (PSD) function of the developed scintillators. [ABSTRACT FROM AUTHOR]

The Nevada National Security Site (NNSS), together with Los Alamos National Laboratory (LANL) and Lawrence Livermore National Laboratory, is developing a novel diagnostic to measure the reactivity of subcritical experiments (SCEs). This capability is known as neutron-diagnosed subcritical experiments (NDSEs). The decay of the fission gamma rays from the neutron-interrogated SCE is measured as a function of time with a large ($\sim 3$ -m diameter) detector wall consisting of 151 individual detector pixels. The data from this current mode measurement inform the neutron multiplication factor, $k_{\mathrm {eff}}$ , and thus the relative reactivity of the SCE. The NNSS developed the Gamma Array Simulation Toolkit (GAST) initially to help inform the design of the individual detector pixels and the 3.4-m diameter detector wall to be fielded as part of NDSEs. This toolkit is now being used to simulate and predict the performance of the final design of the individual detector pixels and the aggregate detector wall. Key detector characteristics evaluated from these simulations include impulse response, pulse height spectrum, number of photoelectrons per MeV, detector efficiency, and crosstalk between detector pixels. Collectively, the results of these simulations inform how well the fission gamma-ray die-off distribution from an NDSE measurement can be resolved. This is critical to determining the relative reactivity of the experiment. Furthermore, the GAST can be used to aid in the analysis of the experimental data from an NDSE measurement once the simulation has been benchmarked. [ABSTRACT FROM AUTHOR]

Currently, plastic (organic) scintillators are using in new type positron emission tomography (PET) devices such as J-PET. But, these type scintillators have low gamma energy detection performance. Therefore, an experimental method was proposed to improve gamma ray energy resolution of an organic scintillation detector composed of a BC-420 type crystal. To do this, a timing spectrometer using constant fraction discrimination method was used. Gamma rays from a 137Cs radioactive source were first detected directly then through the timing method, and the obtained results were compared. The results showed that used method is considerably successful in increasing the energy resolution of this type detector. So, it is believe that the J-PET detection performance will be able to enhance if the proposed method can be used in its electronics. [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]

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]

Neutron and gamma-ray imaging systems are deployed within the field of nuclear safeguards for the detection and localization of special nuclear materials and other materials of interest. 237Np is one of these materials of interest due its presence in spent nuclear fuel and potential for use in nuclear weapons when purified. Here, for the first time, a 6 kg neptunium sphere (98.8 wt% 237Np) was measured using a dual-particle imager, from the University of Michigan, consisting of organic glass and inorganic scintillators. The novel composition of organic glass scintillator was recently developed at Sandia National Labs and has been used in particle imaging systems due to its time resolution and particle discrimination capabilities. Gamma-ray energy spectra from single and coincident events were extracted and the sequencing of Compton scatter and photoelectric absorption gamma-ray events was used to generate images using simple backprojection. The emissions of interest in this work are the 312 keV and 416 keV gamma rays from 233Pa, a daughter isotope from the neptunium decay series. The results of this work show that there is close agreement between the true source location in angular space and the converged location from the gamma ray images created using the system. The gamma spectroscopy from single and coincident events also identified the characteristic emission from the daughter isotope and could be used to assist with the identification of 237Np. Furthermore, successful localization of the source with 5 s of data demonstrates the practical application of the imaging system for imaging and detection of material in weapons-useable quantities. [ABSTRACT FROM AUTHOR]

Emerging thorium-based reactor designs and fuel cycles present challenges to traditional non-destructive assay techniques used in international safeguards. Specifically, assaying the masses of 233U and 235U when they are present together in samples with high gamma ray backgrounds is difficult because of similar passive neutron signatures and relatively weak gamma-ray emissions of 233U. The Pacific Northwest National Laboratory (PNNL) and the Massachusetts Institute of Technology (MIT) are developing a portable neutron resonance transmission analysis (pNRTA) system as one potential solution to these challenges. This method provides isotopic concentration data for a sample via neutron time-of-flight (TOF) measurements that exploit epithermal neutron resonance cross-sections. A recently developed pNRTA system uses a commercially available, pulsed deuterium-tritium neutron generator with a ∼2 m flight path and a GS20 lithium glass scintillator detector. This paper describes the prototype pNRTA system design, a refined radiation transport model of the system, preliminary measurements with thorium and uranium sources, and demonstration of a quantitative isotopic estimation algorithm. [ABSTRACT FROM AUTHOR]

In this work, we propose a prototype of a compact detector assembly capable of discriminating between neutrons and gamma rays, by performing pulse shape analysis. The device takes advantage of recent improvements in silicon photomultiplier (SiPM) technology and the excellent neutron/gamma-ray discrimination capabilities of new plastics and standard liquid scintillators. Our work is focused on the read-out of small-, medium-, and large-sized organic scintillators with large-area SiPM arrays ($4 \times 4$ NUV and RGB-SiPM arrays, 17 mm $\times$ 17 mm). In particular, we used EJ-276 (and its old version EJ-299) and EJ-276G plastic scintillators of several sizes (ranging from 20- to 50-mm diameter) and two large liquid scintillator cells (EJ-301 and EJ-309, 50 mm diameter $\times 50$ mm thickness). Moreover, we show the comparison of neutron/gamma-ray discrimination performance between SiPM and standard photomultiplier read-out configurations. The presented innovative device could be used in different fields, first in fundamental nuclear physics experiments, as an ancillary neutron detector for the active target at the selective production of exotic species (SPES) facility at the Legnaro National Laboratories in Italy. Additionally, it could be used in radiation monitoring applications, as a fast neutron/gamma-ray counter to be embedded in unmanned vehicles for radiation monitoring. [ABSTRACT FROM AUTHOR]

Obtaining directional information is required in many applications such as nuclear homeland security, contamination mapping after a nuclear incident and radiological events, or during the decontamination work. However, many directional radiation detectors are based on directional shielding, made of lead or tungsten collimators, introducing two main drawbacks. The first is the size and weight, making those detectors too heavy and irrelevant for utilization in handheld devices, drone mapping, or space applications. The second drawback is the limited field of view (FOV), which requires multiple detectors to cover the whole required FOV or machinery to rotate the detector’s narrow FOV detector. We propose a novel $4\pi $ directional detector based on a segmented hollow cubic detector, which uses the Compton effect interactions with no heavy collimators. The symmetrical cubical design provides both higher efficiency and $4\pi $ detection ability. Instead of the traditional two types of detectors (scatterer and absorber) structure, we use the same type of detector, based on Gd3Al2Ga3O12 (GAGG) (Ce) scintillator coupled to silicon photomultiplier. An additional advantage of the proposed detector is obtained by locating the photon sensors inside the detector, behind the scintillators, which improves the radiation hardness required for space applications. Furthermore, such an arrangement flattens the temperature variation across the detector, providing better gain stability. The main advantage of the proposed detector is an efficient $4\pi $ radiation detection for high-energy gamma rays without the use of heavy collimators. [ABSTRACT FROM AUTHOR]

This work addresses the use of plastic scintillators as an alternative to 3He neutron detectors for radioactive waste drum characterization. The time response of scintillators is three orders of magnitude faster than that of gas proportional counters, and they offer similar neutron detection efficiency at lower cost. However, they are sensitive to gamma rays and the neutron-gamma pulse shape discrimination (PSD) is not possible with standard PVT scintillators. The proposed approach uses the neutron and gamma times of flight in triple coincidences recorded with 252Cf, AmBe, and 60Co sources. A 2-D histogram of time delays between the second and first detected pulses, on the $x$ -axis, and between the third and second pulses, on the $y$ -axis, evidences a specific region of interest for spontaneous fission coincidences. MCNPX-PoliMi simulations are performed, which are in good agreement with previous experiments and allow for investigating the types of coincidences ($\gamma \gamma \gamma $ , nnn, $\gamma $ nn, $\gamma \gamma \text{n}$) and optimizing the rejection of neutron and gamma scattering crosstalk. The method was also experimentally tested with a 118-L mock-up drum filled with a metallic or an organic matrix, showing a correct estimation of the net fission signal up to an “alpha ratio” of 12 between fission and ($\alpha $ ,n) neutron emissions. Matrix and localization effects were also measured, showing a sensitivity (useful signal per gram of 240Pueq) for a homogeneous distribution of plutonium in the iron matrix about three times larger than in the wood matrix, due to neutron slowing-down in the latter. This difference can be taken into account by the prior knowledge of the matrix characteristics or by neutron and gamma attenuation measurements. In contrast, in case of a point source with an unknown position in the matrix, the relative localization uncertainty is 26% for the metallic drum, and 41% for the organic one. [ABSTRACT FROM AUTHOR]

The charged particles and photon interaction parameters of CsI(Na) scintillator were calculated by the theoretically computational program. The Phy-X programs were used to calculation gamma rays interaction at an energy range of 1 keV to 100 GeV. The stopping and range of ions in matter program were used for measurement the proton and alpha particles. The result found that the total mass attenuation coefficient decreased with the increasing of the high photon energy range and found the discontinuous energy due to the absorption edge of Cs and I. The effective atomic number and the effective electron density found the same trend with the total mass attenuation coefficient. The data of mass stopping powers for proton and alpha particle increase to the maximum value at kinetic energy 0.09, 0.6 MeV, respectively. The results showed that the energy at 5 keV, the ions entering the scintillator penetrate less deeply than the energy of the ions at 10 keV. [ABSTRACT FROM AUTHOR]

Lithium iodides are very efficient single‐crystal scintillators for thermal neutron detection. Doping with silver, as activator ions, has shown to improve its limitation of discriminating gamma background by introducing pulse shape discrimination ability. To improve the scintillation performance, single crystals of LiI:Ag, codoped with different concentration of Sr ions, are grown and characterized in details. A systematic investigation of radioluminescence, thermoluminescence, and scintillation properties along with the decay kinetics provides better understanding about the role of defect structure in scintillation mechanism. The extra charge, provided by Sr2+ ions, is found to alter the defect structure with relative reduction of the contribution from the deeper trap centers in comparison with the shallow traps. Consequently, it leads to a significant improvement of light yield quenching under higher excitation density of charged particle irradiation. The 0.1% Sr codoped crystals provide a better discrimination ability of neutron and gamma radiations for simultaneous detection. [ABSTRACT FROM AUTHOR]

Purpose: To present an x‐ray tube system capable of in vitro ultrahigh dose‐rate (UHDR) irradiation of small < 0.3 mm samples and to characterize it by means of a plastic scintillation detector (PSD). Methods and materials: A conventional x‐ray tube was modified for the delivery of short UHDR irradiations. A beam shutter system with a sample holder was designed and installed in a close proximity of an x‐ray tube window to enable <1 s irradiations at UHDR. The dosimetry was performed with a small 0.5‐mm long 0.5‐mm in diameter PSD irradiated with 80, 100, and 120 kVp beams and beam currents of 1–37.5 mA. The PSD signal was recorded at frame rates of 20 and 50 fps for shutter exposure between 100 and 1125 ms. Irradiation reproducibility was studied with the PSD. The x‐ray tube irradiation setup was modeled with Monte Carlo (MC) and dose on a surface of a phantom was also measured with films. The effect of dose delivery uncertainty to 300‐μm spheroids due to positioning and spheroid size was evaluated. Results: MC simulations showed good agreement with PSD measurements acquired at both frame rates of 20 and 50 fps in terms of beam temporal profile. PSD‐measured dose exhibited excellent linearity as a function of instantaneous dose rate from 3.1 to 118.0 Gy/s as well as shutter exposure time from 100 and 1125 ms for all investigated beam energies. PSD absorbed dose for the 80, 100, and 120 kVp beams agreed with MC simulations to within 5%. The total delivered doses ranged from 0.4 Gy for a 1‐mA, 80 kVp beam, and 100 ms shutter exposure to 166.9 Gy for a 37.5‐mA, 80 kVp beam, and a 1125 ms exposure. PSD irradiation reproducibility was < 0.5%. Simulated and measured dose fall off agreed and it was steep along the axis of the shutter slit (1%/0.1 mm) and with depth (2%/0.1 mm at 1‐mm depth). Spheroid positioning uncertainty of 300 μm resulted in dose difference of < 3% for x and y shifts but up to 7% uncertainty for a z‐shift parallel to the beam axis. A 16% difference in spheroid size resulted in <5% dose difference in spheroid absorbed dose. Conclusions: We have presented a cost‐effective x‐ray tube‐based system with a beam shutter designed for in vitro UHDR delivery and reaching dose rates of up to 118.0 Gy/s. The described shutter system can be easily implemented at other institutions, which might enable new researchers to investigate the radiobiology of UHDR irradiations in vitro. [ABSTRACT FROM AUTHOR]

The improvement of sensor technologies and electronics enabled to separately detect neutrons and gamma rays with a single radiation detector. There are various detectors for neutron/gamma detection based on scintillators, such as liquid, plastic scintillators, currently commercialized CLLB, NaIL, and CLYC. The purposes of this study are to evaluate and compare the performance of various scintillation detectors. This study focuses on the performance evaluation of the scintillation detectors with conventional PSD methods, such as charge comparison method (CCM). Additionally, a preliminary result of machine learning PSD of the CLLB and EJ-276 detector was presented. [ABSTRACT FROM AUTHOR]

Cs2 LiLaBr6: Ce(CLLB: Ce) crystal has excellent neutron-gamma dual readout performance, while its application bottleneck is to grow single crystals with large size and high optical quality. In this study, non-stoichiometric ratio was used to avoid the phase region of in-congruent CLLB: Ce. By improved Bridgman furnace, optimizing the temperature field and reducing the lowering speed, the constitutional supercooling was overcame and the stability of the growth interface was maintained during the crystal growth process. 1-inch diameter CLLB: Ce crystal ingot was obtained, the length of the equal diameter transparent part is 40 mm, the proportion of single crystal increases from 52% to 79%, and the optical transmittance in the visible light region is above 70%. The energy resolution of CLLB: Ce is about 3.7% under 137Cs excitation while the Figure-of- Merit of CLLB: Ce is about 1.42 under 252Cf excitation. This shows good properties for discriminating gamma-ray and neutron. [ABSTRACT FROM AUTHOR]

Purpose of this research was to find the best blue-emitting fluorescent substance for plastic scintillator used for gamma radiation dosimetry. Scintillator should convert gamma radiation into blue light with high efficiency. Plastic scintillators with fixed concentration of various fluorescent additives, called wavelength shifters, absorbing ultraviolet light and emitting blue light were manufactured by radical bulk polymerization of styrene. Light output were measured and compared to the light output of commercial plastic scintillator. Performed measurements of charge Compton spectra confirmed usefulness of majority of researched substances as wavelength shifters in plastic scintillators with emission maximum at blue range of visible light. Plastic scintillation dosimeter may be constructed from manufactured polystyrene-based scintillators. Performance of synthesized scintillators is close to commercial polystyrene scintillators. [ABSTRACT FROM AUTHOR]

A transimpedance amplifier (TIA) is an essential electronic circuit in prompt gamma detection. To improve the performance and reliability of the electronics, we designed a TIA using GaN high electron mobility transistor (HEMT) as it is more radiation-hardened when compared to its silicon counterpart and it has lower noise. Our circuit is designed using GaN HEMT from efficient power conversion (EPC) and has a 3-dB frequency of 21 MHz and 45 dB Ω of transimpedance gain. Its total output rms noise voltage is 3.1 mV. Its functionality is verified using a Lu-176 radiation source, and experimental result shows that the current generated from the H12700 position-sensitive photomultiplier tube (PSPMT) detector when the gamma radiation hits the scintillator crystal is successfully converted into voltage with the gain in agreement with our simulation result. Comparison of this GaN-based TIA with the reported silicon-based TIA shows superior performances for particle therapy imaging. The circuit is also tested under 100-MeV proton radiation with a fluence of 1.6 × 1011 c−2 and flux of 1.14 × 108 cm−2 s−1, and negligible variations in the linearity and gain in the postradiation measurements are observed. [ABSTRACT FROM AUTHOR]