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The characteristics of neutron scintillation detectors built on monolithic and heterogeneous scintillators containing 6Li were studied. The detectors were tested on a thermal neutron beam and on a stand with a source of γ-quanta 60Co. To process the signals received from the detector with a monolithic scintillator, three different γ-radiation discrimination algorithms were used: registration of pulses at a constant threshold and selection according to the pulse shape using two digital signal separation methods: charge integration and pulse duration measurement. For a homogeneous scintillator, pulse shape selection methods work approximately the same when separating thermal neutrons and γ-quanta and are significantly inferior to the method of registration at a constant threshold. In this case, the quality of the n/γ separation is worse than the result obtained with a heterogeneous scintillator when recording at a constant threshold. The purpose of the work is to compare the results of using digital methods for discrimination of gamma-quanta with the results obtained using heterogeneous scintillators. [ABSTRACT FROM AUTHOR]

Fast and high‐linearity detection of fast neutron is vital for special nuclear material seeking, nuclear accident emergency response, nondestructive neutron imaging, and neutron cancer therapy. Neutron scintillators with fast time resolution and linear energy response are indispensable for precisely acquiring the energy and temporal evolution of fast neutron, but none of the conventional neutron scintillators, whether organic, two‐component or inorganic, have performed well in this regard. To address these challenges, it is urgent to develop novel neutron scintillators. Here, 2D hybrid perovskite single crystals (C4H12N)2PbBr4 (BA2PbBr4) successfully combined with fast response time of 2.66 ns and linear energy response to fast neutrons, γ ray, and α particle, is reported. The rapid response time and linear energy response of 2D hybrid perovskite scintillator originate from intensive states density of lead halide frameworks, which are the key fluorescence emitters under neutron irradiation. This effectively suppresses the ionization quenching effect during the fluorescence process. This work represents a milestone in fast neutron detection, demonstrating a new type of neutron scintillator based on 2D hybrid perovskite single crystals with fast and high‐linearity detection characteristics, having great potential in high precision neutron spectrum measurement and nuclear reaction kinetics monitoring. [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]

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

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]

Scintillator‐based ZnS:Ag/6LiF neutron detectors have been under development at ISIS for more than three decades. Continuous research and development aim to improve detector capabilities, achieve better performance and meet the increasingly demanding requirements set by neutron instruments. As part of this program, a high‐efficiency 2D position‐sensitive scintillator detector with wavelength‐shifting fibres has been developed for neutron‐diffraction applications. The detector consists of a double scintillator‐fibre layer to improve detection efficiency. Each layer is made up of two orthogonal fibre planes placed between two ZnS:Ag/6LiF scintillator screens. Thin reflective foils are attached to the front and back scintillators of each layer to minimize light cross‐talk between layers. The detector has an active area of 192 × 192 mm with a square pixel size of 3 × 3 mm. As part of the development process of the double‐layer detector, a single‐layer detector was built, together with a prototype detector in which the two layers of the detector could be read out separately. Efficiency calculations and measurements of all three detectors are discussed. The novel double‐layer detector has been installed and tested on the SXD diffractometer at ISIS. The detector performance is compared with the current scintillator detectors employed on SXD by studying reference crystal samples. More than a factor of 3 improvement in efficiency is achieved with the double‐layer wavelength‐shifting‐fibre detector. Software routines for further optimizations in spatial resolution and uniformity of response have been implemented and tested for 2D detectors. The methods and results are discussed in this manuscript. [ABSTRACT FROM AUTHOR]

Knowledge of the neutron light-yield response is crucial to the understanding of scintillator-based neutron detectors. In this work, neutrons from 2–6 MeV have been used to study the scintillation light-yield response of the liquid scintillators NE 213A, EJ 305, EJ 331 and EJ 321P using event-by-event waveform digitization. Energy calibration was performed using a GEANT4 model to locate the edge positions of the Compton distributions produced by gamma-ray sources. The simulated light yield for neutrons from a PuBe source was compared to measured recoil proton distributions, where neutron energy was selected by time-of-flight. This resulted in an energy-dependent Birks parameterization to characterize the non-linear response to the lower energy neutrons. The NE 213A and EJ 305 results agree very well with existing data and are reproduced nicely by the simulation. New results for EJ 331 and EJ 321P, where the simulation also reproduces the data well, are presented. [ABSTRACT FROM AUTHOR]

Two organic scintillators (EJ309 and stilbene) with their different detection chains and elaborate software were used to measure neutron spectra of AmBe and PuC sources. Method of shadow cone ensures minimization of scattered neutron influence. To separate neutrons and γ, a modern method of pulse shape discrimination was employed using fast digitizers. Calibration was performed by γ sources and three different methods for the identification of the Compton edge. Spectrometric systems also used different light output functions and unfolding methods. The same spectra were calculated using the MCNP6 code and the JENDL-5 library. The measured and calculated results were mutually compared, and also with the published results available in the literature. Generally, the results agree on the main peaks of neutron spectra but differ in their abundance. The lower limit for the ability to distinguish between neutrons and γ in spectrometry with organic scintillators was found at about 1.5 MeV. • Neutron spectra of AmBe and PuC sources were measured and calculated. • The measured/unfolded spectra and calculated ones agree in shape. • Methods of energy calibration and neutron/gamma separation are described. [ABSTRACT FROM AUTHOR]

A scintillator-based Timepix3 (TPX3) detector was developed to resolve the high-frequency modulation of a neutron beam in both spatial and temporal domains, as required for neutron spin-echo experiments. In this system, light from a scintillator is manipulated with an optical lens and is intensified using an image intensifier, making it detectable with the TPX3 chip. Two different scintillators, namely, 6LiF:ZnS(Ag) and 6LiI:Eu, were investigated to achieve the high resolution needed for spin-echo modulated small-angle neutron scattering (SEMSANS) and modulation of intensity with zero effort (MIEZE). The methodology for conducting event-mode analysis is described, including the optimization of clustering parameters for both scintillators. The detector with both scintillators was characterized with respect to detection efficiency, spatial resolution, count rate, uniformity, and γ-sensitivity. The 6LiF:ZnS(Ag) scintillator-based detector achieved a spatial resolution of 200 μm and a count rate capability of 1.1 × 105 cps, while the 6LiI:Eu scintillator-based detector demonstrated a spatial resolution of 250 μm and a count rate capability exceeding 2.9 × 105 cps. Furthermore, high-frequency intensity modulations in both spatial and temporal domains were successfully observed, confirming the suitability of this detector for SEMSANS and MIEZE techniques, respectively. [ABSTRACT FROM AUTHOR]

III-nitrides have fomented a revolution in the lighting industry and are poised to make a huge impact in the field of power electronics. In the III-nitride family, the crystal growth and use of hexagonal BN (h-BN) as an ultrawide bandgap (UWBG) semiconductor are much less developed. Bulk crystals of h-BN produced by the high-temperature/high-pressure and the metal flux solution methods possess very high crystalline and optical qualities but are impractical to serve as substrates or for device implementation as their sizes are typically in millimeters. The development of crystal growth technologies for producing thick epitaxial films (or quasi-bulk or semi-bulk crystals) in large wafer sizes with high crystalline quality is a prerequisite for utilizing h-BN as an UWBG electronic material. Compared to traditional III-nitrides, BN has another unique application as solid-state neutron detectors, which however, also require the development of quasi-bulk crystals to provide high detection efficiencies because the theoretical efficiency (ηi) relates to the detector thickness (d) by η i = 1 − e − d λ , where λ denotes the thermal neutron absorption length which is 47 μm (237 μm) for 10B-enriched (natural) h-BN. We provide an overview and recent progress toward the development of h-BN quasi-bulk crystals via hydride vapor phase epitaxy (HVPE) growth and the attainment of thermal neutron detectors based on 100 μm thick 10B-enriched h-BN with a record efficiency of 60%. The thermal neutron detection efficiency was shown to enhance at elevated temperatures. Benchmarking the crystalline and optical qualities of h-BN quasi-bulk crystals with the state-of-the-art mm-sized bulk crystal flakes and 0.5 μm thick epitaxial films identified that reducing the density of native defects such as vacancies remains the most critical task for h-BN quasi-bulk crystal growth by HVPE. [ABSTRACT FROM AUTHOR]

The 3He gas is commonly used for the detection of thermal neutrons. However, with the depletion of 3He gas, there is a need to develop new solid scintillators for thermal neutron detection. Solid scintillators containing 6Li, which have large neutron capture cross-sections and a large amount of energy released by transmutation reactions, are commonly used as alternative candidates. However, only single-crystal scintillators are currently used, and their 6Li concentration is limited by their chemical composition. In this study, we designed, grew, and evaluated a new eutectic scintillator, Rb2CeCl5/LiCl, which can improve the 6Li concentration compared with single-crystal scintillators. Rb2CeCl5, which was selected as the scintillator phase, has excellent scintillator properties (light yield: 36,000 photons/MeV, decay time: mostly 24 ns, slightly 153 ns), and is less deliquescent than other halide scintillators. The crystal grown using the vertical Bridgman method exhibited a eutectic phase composed of Rb2CeCl5 and LiCl. The eutectic crystals exhibited Ce3+ 5d-4f emissions, with a peak between 360 and 370 nm. The Rb2CeCl5 phase was identified as the luminescent phase via cathodoluminescence mapping, and 16,000 photons/neutron of the light yield and 56.1 ns of the decay time were observed. This study indicates that the Rb2CeCl5/LiCl eutectic scintillator is a promising candidate for use in thermal neutron detectors. [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]

Neutron diffraction beamlines have traditionally relied on deploying large detector arrays of 3He tubes or neutron‐sensitive scintillators coupled with photomultipliers to efficiently probe crystallographic and microstructure information of a given material. Given the large upfront cost of custom‐made data acquisition systems and the recent scarcity of 3He, new diffraction beamlines or upgrades to existing ones demand innovative approaches. This paper introduces a novel Timepix3‐based event‐mode imaging neutron diffraction detector system as well as first results of a silicon powder diffraction measurement made at the HIPPO neutron powder diffractometer at the Los Alamos Neutron Science Center. Notably, these initial measurements were conducted simultaneously with the 3He array on HIPPO, enabling direct comparison. Data reduction for this type of data was implemented in the MAUD code, enabling Rietveld analysis. Results from the Timepix3‐based setup and HIPPO were benchmarked against McStas simulations, showing good agreement for peak resolution. With further development, systems such as the one presented here may substantially reduce the cost of detector systems for new neutron instrumentation as well as for upgrades of existing beamlines. [ABSTRACT FROM AUTHOR]

The BC501A sensor is a liquid scintillator frequently used in nuclear physics for detecting fast neutrons. This paper describes a hardware implementation of digital pulse shape analysis (DPSA) for real-time analysis. DPSA is an algorithm that extracts the physically relevant parameters from the detected BC501A signals. The hardware solution is implemented in a MicroTCA system that provides the physical, mechanical, electrical, and cooling support for an AMC board (NAMC-ZYNQ-FMC) with a Xilinx ZYNQ Ultrascale-MP SoC. The Xilinx FPGA programmable logic implements a JESD204B interface to high-speed ADCs. The physical and datalink JESD204B layers are implemented using hardware description language (HDL), while the Xilinx high-level synthesis language (HLS) is used for the transport and application layers. The DPSA algorithm is a JESD204B application layer that includes a FIR filter and a constant fraction discriminator (CFD) function, a baseline calculation function, a peak detection function, and an energy calculation function. This architecture achieves an analysis mean time of less than 100 µs per signal with an FPGA resource utilization of about 50% of its most used resources. This paper presents a high-performance DPSA embedded system that interfaces with a 1 GS/s ADC and performs accurate calculations with relatively low latency. [ABSTRACT FROM AUTHOR]

In deep-underground experiments, intrinsic detector background can exceed the external one, limiting the detection sensitivity. Intrinsic background in liquid scintillator neutron detectors consists of α particles emitted from radioactive impurities in the detector housing (and possibly in the liquid). We present the results of long background measurements of 12 EJ-309 liquid organic scintillators detectors in the deep-underground Gran Sasso National Laboratory of the Italian Institute of Nuclear Physics. These detectors are a part of the detection array for the SHADES ERC project that aims to measure the very low cross section (down to picobarn) of the astrophysically important reaction 22 Ne (α , n) 25 Mg. With an exposure of ∼ 35 days we identify an actinide concentration in the detector housing of 8. 4 (1. 8) sta (1. 4) sys × 1 0 − 2 ppm and 1. 62 (0. 57) sta (0. 03) sys × 1 0 − 1 ppm of 238 U and 232Th, resulting in 64 α particle counts per hour. The half-life of 214Po was also determined as 163. 7 (11) μ s. [ABSTRACT FROM AUTHOR]

A new neu tron SIM ulation program based on the versatile GEANT 4 toolkit, neuSIM4 , has been developed to describe interactions of neutrons in the NE213 liquid scintillator from 0.1 to 3000 MeV. neuSIM4 is designed to accommodate complicated modern detector geometry setups with multiple scintillator detectors, each of which can be outfitted with more than one photo-multiplier. To address a broad spectrum of neutron energies, two new neutron interaction physics models, KSCIN and NxQMD, have been implemented in GEANT4. For neutrons with energy below 110 MeV, we incorporate a total of eleven neutron induced reaction channels on hydrogen and carbon nuclei, including nine carbon inelastic reaction channels, into KSCIN. Beyond 110 MeV, we implement a neutron induced reaction model, NxQMD, in GEANT4. We use its results as reference to evaluate other neutron-interaction physics models in GEANT4. We find that results from an existing cascade physics model (INCL) in GEANT4 agree very well with the results from NxQMD, and results from both codes agree with new and existing light response data. To connect KSCIN to NxQMD or INCL, we introduce a transition region where the contribution of neuSIM4 linearly decreases with corresponding increased contributions from NxQMD or INCL. To demonstrate the application of the new code, we simulate the light response and performance of a 2 × 2 m2 neutron detector wall array consisting of 25 2m-long scintillation bars. We are able to compare the predicted light response functions to the shape of the experimental response functions and calculate the efficiency of the neutron detector array for neutron energies up to 200 MeV. These simulation results will be pivotal for understanding the performance of modern neutron arrays with intricate geometries, especially in the measurements of neutron energy spectra in heavy-ion reactions. [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]

• 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]

Pulse shape discrimination of a liquid scintillator-based detector (BC501A) has been studied using a digital approach. The objective of this work is to develop a new neutron-gamma discrimination algorithm to improve the discrimination efficiency. The new approach is a combination of two parts. The first part uses an adaptive Sallen-Key filter to reduce noise in the pulse followed by traditional approaches of either charge comparison or time over threshold. The approach of adaptive Sallen-Key combined with time over threshold was found to have a much better capability to discriminate neutron events from that of gamma. The pulse shape discrimination performance obtained for a 5 inches by 5 inches (length by diameter) liquid scintillator detector using the combination of the adaptive Sallen-Key filter with time over threshold is found to be significantly higher compared to that obtained using traditional methods. Moreover, this combination has the potential for real-time hardware implementation. [ABSTRACT FROM AUTHOR]

• G2 glass matched with F2 glass (Schott) was used to draw fiber. • A linear increase and efficient response at 374 nm were obtained in G2 glass with X-ray radiation. • G2 glass material has an ideal and stable optical response. • G2 glass fiber has an emission at about 375 nm and a short fluorescence lifetime (2.22 ns). In order to enrich the application demands of neutron detection field, this study prepared a series of Ce3+/Gd3+ co-doped borosilicate scintillating glass materials. The ultraviolet (UV) absorption edges were all below 400 nm. The optical band gap was shortened from 3.48 eV to 3.24 eV as well as the optical basicity increased from 0.4941 to 0.5063 with the added concentration of Gd3+ ions. When the samples were excited by a 330 nm light source, the central wavelength of the emission spectra was 375 nm. The fluorescence lifetime of the sample was 30.99 ns. The emission intensity of the G2 sample increases linearly with the increase of X-ray excitation current, and has a stable optical response at 374 nm. The G2 glass fiber with the highest fluorescence intensity had a prominent emission peak at 375 nm and the fluorescence lifetime of 2.22 ns. [ABSTRACT FROM AUTHOR]

This paper presents the performance of polystrene based plastic scintillator produced in Turkish Energy, Nuclear and Mineral Research Agency (TENMAK). The scintillator is manufactured using thermal polymerization of commercially available styrene monomer doped with first and second fluorescent dyes. The absorption spectrum of the scintillator exhibited two absorption bands at 225 nm and 340 nm, with an absorption edge observed at 410 nm. The wavelength of the emitted light was measured in the range of 400–800 nm, with a maximum intensity at 427 nm. Internal conversion electrons from the 137Cs source were used to evaluate the characteristics of the new scintillator, particularly its light yield. As the light readout the MAPD-3NM type silicon photomultiplier array (4 × 4) with an active area of 15 × 15 mm 2 , assembled using single MAPDs with an active area of 3.7 × 3.7 mm 2 , was used. The light yield of the scintillator was determined to be 6134 photons/MeV. In addition, the efficiency of the scintillator for gamma rays with an energy of 662 keV was found out to be approximately 1.8%. CmBe neutron source was employed to evaluate its fast neutron detection performance. However, neutron/gamma discrimination using pulse shape discrimination (charge integration) method was not observed. The results demonstrate the potential of produced plastic scintillator for various applications, particularly in radiation monitoring and detection systems. • The scintillator is manufactured using thermal polymerization of commercially available styrene monomer doped with first and second fluorescent dyes. • Plastic scintillator exhibits two absorption bands at 225 and 340 nm, with an absorption edge observed at 410 nm. • The efficiency of the scintillator for gamma rays with an energy of 662 keV was found out to be approximately 1.8%. • The plastic scintillator coupled to micropixel avalanche photodiode demonstrated effective detection of beta particles emitted by 137Cs and 90Sr sources, with an energy resolution of 25% for monoenergetic (626 keV) electrons. [ABSTRACT FROM AUTHOR]

Large area thermal neutron detectors are applied in many fields including industrial imaging, nuclear safeguarding, neutron scattering, and fundamental science. Historically, these detectors were based on 3He gas proportional counters despite the limitations of 3He detectors such as high cost, limited supply, non-uniform spatial resolution, and depth of absorption problems. Two alternatives to 3He detectors are 6Li-loaded glass scintillators, and powdered ZnS(Ag) scintillators mixed with 6LiF neutron converters. The 6LiF/ZnS(Ag) scintillator has advantages over 6Li glass as it is less expensive and can be produced in larger areas, although its self-absorption presents a problem. In this work, we developed a large area thermal neutron detector based on 6LiF/ZnS(Ag) scintillator coupled with wavelength shifting fibers. The detector uses resistive charge divider-based position encoding. We further modified and improved the method by 2D segmentation of the detector using modular multichannel readout electronics. This segmentation approach allows for a combination of large detector area, improved spatial resolution, and increased count rate. Furthermore, spatial resolution can be variable across the detector area by adjusting the segment size. [ABSTRACT FROM AUTHOR]

High-energy photon interrogation has established itself as a valuable tool for detecting special nuclear materials and characterizing nuclear waste. Previous research predominantly uses around 9-MV linear electron accelerators (LINACs) as photon sources and limited exploration has been conducted on the use of organic scintillators to determine the energy deposited in the detector and to separate photon and neutron radiation, crucial when the photon interrogation is based on the measurement of the neutron emission. The challenge arises from the intense photon flux typically produced by electron accelerators, resulting in issues such as pulse pile-up, detector saturation, and a suboptimal signal-to-background ratio. This study aims to extend the applicability of the conventional Active Photon Interrogation (API) techniques by introducing a novel method enabling the detection, in addition to nuclear materials, of light elements—specifically nitrogen, oxygen, and carbon—known to be present in conventional explosives, narcotics, and chemical weapons. The approach relies on active photon interrogation at high energies above 12 MeV, coupled with photoneutron spectrometry. Using a 22-MV electron LINAC, pulse shape discrimination with an organic liquid scintillator demonstrated promising performance. Our results highlight that the conventional pulse shape discrimination capabilities and rapid time-scale operation of organic scintillators enable the detection of fast neutrons from (γ,Xn) reactions, even in a mixed short-pulsed field of photon and neutron radiation with intense photon flashes. This exploration of the initial experimental aspects of photoneutron detection induced by high-energy photons establishes a foundation for a promising new method for the detection of illicit materials. [ABSTRACT FROM AUTHOR]

Non-doped and Ce-doped LiAl 5 O 8 single crystals were prepared to investigate their properties as a neutron detector. The 1% Ce-doped LiAl 5 O 8 indicated photoluminescence and scintillation peaks at around 340, 430, and 700 nm. From the viewpoint of the results of decay profiles, the peaks at 340 and 430 nm are due to 5d-4f transition of Ce3+, and the peak at 700 nm is caused by Fe3+. The clear thermal neutron peaks were detected regardless of Ce concentration. The LY of the non-doped, 0.1, 0.3, and 1% Ce-doped LiAl 5 O 8 was estimated to be 390, 443, 446, and 468 ph/n. [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]

• Phase diagram for the CsI-LiBr binary system established. • Vertical Bridgman method employed for crystal growth. • Homogeneous eutectic crystals obtained. • Light yield (thermal neutron irradiation) was 6.7 times higher than that of the LiCAF. • This helps development of eutectic scintillators with improved crystal structure. 3He gas detectors have been commonly used in applied technology related to thermal neutron detectors; however, owing to the depletion of 3He, applications using solid-state scintillators are expanding. In recent years, our group has reported a novel Tl:CsI/6LiBr eutectic scintillator for thermal neutron detection, which has excellent light yield and (n,γ) discrimination ability. In practical applications of eutectic scintillators, achieving eutectic production precisely at the eutectic point is crucial to ensure a high production yield and the development of a uniform eutectic structure. However, the phase diagram of the CsI-LiBr system has not yet been reported. In this study, the phase diagram obtained from calorimetry was investigated. Furthermore, eutectic fabrication was performed at the eutectic point, and the neutron response was evaluated. [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]

Moon is an auspicious environment for the study of Galactic cosmic rays (GCR) and Solar Particle Events (SEP) due to the absence of magnetic field and atmosphere. The same characteristics raise the radiation risk for human presence in orbit around it or at the lunar surface. The secondary (albedo) radiation resulting from the interaction of the primary radiation with the lunar soil adds an extra risk factor, because neutrons are produced, but also it can be exploited to study the soil composition. In this paper, the design of a comprehensive radiation monitor package tailored to the lunar environment is presented. The detector, named LURAD, will perform spectroscopic measurements of protons, electrons, heavy ions, as well as gamma-rays, and neutrons. A microdosimetry monitor subsystem is foreseen which can provide measurements of LET(Si) spectra in a wide dynamic range of LET(Si) and flux for SPE and GCR, detection of neutrons and biological dose for radiation protection of astronauts. The LURAD design leverages on the following key enabling technologies: (a) Fully depleted Si monolithic active pixel sensors; (b) Scintillators read by silicon photomultipliers (SiPM); (c) Silicon on Insulator (SOI) microdosimetry sensors; These technologies promise miniaturization and mass reduction with state-of-the-art performance. The instrument's design is presented, and the Monte Carlo study of the feasibility of particle identification and kinetic energy determination is discussed. [ABSTRACT FROM AUTHOR]

Improved neutron inelastic scattering cross section data are needed to inform integral benchmark studies and advance applications in a wide variety of areas including nuclear energy, stockpile stewardship, nonproliferation, and space exploration. Neutron inelastic scattering also serves as a non-selective probe of low-lying nuclear structure. To help meet these needs, the Gamma Energy Neutron Energy Spectrometer for Inelastic Scattering (GENESIS) was constructed at the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. This array couples high-resolution γ -ray detectors and fast neutron detectors to achieve single and coincident n/ γ detection over a broad energy range. The current configuration of the array includes 26 organic liquid scintillators and four high-purity germanium detectors (two single-crystal and two four-crystal CLOVER detectors with two-fold segmentation). The array was constructed with minimal supporting material and designed to cover a wide range of secondary particle angles and energies with limited inter-element scattering. Data acquisition is accomplished using Mesytec MDPP-16 multi-channel high-resolution digital pulse processing modules. The array characteristics, including γ -ray and neutron energy resolution, timing resolution, and detection efficiency were measured and used to validate a Geant4 model of the array. The primary sources of neutron background and the uncertainties in the determination of incident and secondary neutron energy were assessed. GENESIS provides a new capability to address nuclear data needs and facilitates the advancement of a wide range of nuclear applications. [ABSTRACT FROM AUTHOR]

The utilization of large-scale neutron detector arrays in future experiments is of vital importance to increase our understanding of β -delayed neutron emitters. A new device, DAEMON (Detector Array for Energy Measurements Of Neutrons), is being designed for the GRIFFIN decay station at TRIUMF-ISAC. DAEMON will improve the precision on the measurement of the neutron kinetic energy through the use of thin plastic scintillators, SiPMs arrays, and the Time-of-Flight technique, to enhance the current capabilities to study neutron rich nuclei at TRIUMF. The performance and feasibility of the DAEMON array was investigated using the Geant4 package to simulate and optimize the experimental design. To test the optical parameters and models implemented in the Geant4 simulations, a comparison with experimental data from small plastic scintillators combined with SiPM detectors was performed. The simulations reproduce the experimental data very well, including features introduced by summing 2 × 2-SiPM arrays in software. This work lays the foundation for simulations of the full DAEMON array. [ABSTRACT FROM AUTHOR]

The use of large-scale neutron detector arrays with high energy resolution, especially those that can be coupled with highly efficient γ -ray spectrometers, is imperative in order to increase the understanding of the decay of β -delayed neutron emitters. The DAEMON array, currently being designed for the GRIFFIN decay station at TRIUMF, will improve the precision on the neutron kinetic energy measurement enhancing the current capabilities to study neutron rich nuclei at TRIUMF. The innovative design for DAEMON uses thin fast plastic scintillators placed directly on the front of the DESCANT liquid scintillator cans. To investigate the viability of this augmentation, Geant4 was used to simulate and optimize the experimental design. Two configurations were considered; a geometry using vertical bars spanning the inner arc of DESCANT, and individual tiles matching the geometry of the DESCANT scintillator cans. The latter was found to be the most optimum design, enabling the project to enter a prototype testing phase. [ABSTRACT FROM AUTHOR]

[Display omitted] • Growth of a crack-free, optical transparent, and large-size trans -stilbene (TSB) single crystal using novel vaporized purification method is reported. • The crystal also exhibits strong blue emission (380 nm) in photoluminescence and emission at 387 nm under X-ray radiation in radioluminescence spectroscopy. • The scintillation decay time is calculated to be 6 ns under 137Cs gamma source. • The figure of merit of 2,4 indicates its potential significance in fast neutron detection with efficient PSD property. The paper reports the successful growth of large, crack-free trans -stilbene (TSB) single crystals using an in-house developed vertical Bridgman setup. The material purification involved a novel vaporized method at 130 °C. Parameters like furnace setup and ampoule's cone angle were optimized during the growth process. The Powder XRD pattern confirms the phase of material and crystallinity. The crystal exhibited high transmittance (78 %) in the visible region, with an optical band gap of 3.4 eV. Photoluminescence study indicated strong blue emission at 380 nm, with radioluminescence spectroscopy showing emissions at 387 nm under X-ray radiation. The crystal exhibited a scintillation decay time of 6 ns under 137Cs gamma source, highlighting its fast decay and efficient PSD property with a figure of merit of 2.24 for fast neutron detection applications. [ABSTRACT FROM AUTHOR]

Trans -stilbene single crystal possesses the advantages of high luminescence efficiency, short response time, stable radiation/strong light resistance and remarkable neutron/gamma pulse shape discrimination (PSD) properties, rendering it arguably the leading candidate for organic scintillators. Here, by the improvement of the thermal field, solvent and sealing on our self-designed equipment, precise growth control resulted trans -stilbene single crystal with high crystalline quality (half peak width of rocking curve of 46.58 arcsec) and size of more than 60 mm. Then we fabricated crystal wafers for the first time to conduct systematic physicochemical measurements to reveal the intrinsic properties of the material. The high-quality single crystals were found to possess high optical transmittance (80%), fast decay time of 2.85 ns (68.49%) and high photoluminescence quantum yield (90.5%), which are more suitable for fast neutrons detection requirements. Thirdly, we conducted a comprehensive exploration of the radiation response of high-quality trans -stilbene single crystals to alpha particles and gamma rays. The results showed a record neutron/gamma discrimination performance with a FOM value of 4.33, which is the highest reported value so far. This work paves the way for practical applications of trans -stilbene and may provide guidance for the selection of detectors for monitoring ionizing radiations under multiple irradiations background. • Large-sized and high-quality trans -stilbene single crystals were grown by our independently designed growth equipment. • The fabrication of wafers from the as-grown single crystals were firstly realized to measure the physical/chemical properties. • The n/γ discrimination of trans -stilbene single crystals showed a FOM value of 4.33, which is the highest value so far. [ABSTRACT FROM AUTHOR]

High sensitivity and high resolution is desired in such technologies as neutron radiography. However, the contamination of gamma photons in neutron images decreases the accuracy of neutron radiography. To solve this problem, we developed an event-by-event based neutron imaging system that can selectively detect neutrons. The developed neutron imaging system consists of an Li–ZnS(Ag) scintillator plate optically coupled to a flat panel photomultiplier tube (FP-PMT) with a light guide. Scintillation light emitted from the Li–ZnS(Ag) by the interaction with neutron-induced particles is used to calculate the position based on the center of mass calculations. The spatial resolution of the neutron imaging detector is ∼2.3 mm FWHM, and the sensitivity for 252Cf at 2 cm from the source with 2-cm-thick polystyrene is 20 cps/MBq. Background count fraction from 60Co gamma photons was 0.2 %. For various types of neutron absorption phantoms, high-contrast and high-resolution neutron images are obtained with the developed neutron imaging detector using a252Cf neutron source. • An event-by-event based neutron imaging system that can selectively detect neutrons was developed. • The spatial resolution of the neutron imaging detector is ∼2.3 mm FWHM. • For various types of neutron absorption phantoms, high-contrast and high-resolution neutron images are obtained. [ABSTRACT FROM AUTHOR]

The challenge of simultaneous measurement of neutrons and gamma rays with good resolution has potential impact on numerous applications in, for example, national security. Here, we employ a phosphor-sandwich style detector, combining Gadolinium-Aluminium-Gallium-Garnet (GAGG(Ce)) and Cerium-Bromide (CeBr 3) scintillators with a silicon photomultiplier for photodetection. Through pulse-shape discrimination (PSD), we are able to distinguish thermal neutron capture on the gadolinium from γ -ray detection in the CeBr 3 with a figure-of-merit in the region-of-interest of 1.406(5). In agreement with previous work we demonstrate that an improved signal-to-background can be achieved through the use of very thin GAGG(Ce) crystals, while also demonstrating the importance of the detector geometry in reducing the low-energy background. [ABSTRACT FROM AUTHOR]

The global challenge of on-site detection of highly enriched uranium (HEU), a substance with considerable potential for unauthorized use in nuclear security, is a critical concern. Traditional passive nondestructive assay (NDA) techniques, such as gamma-ray spectroscopy with high-purity germanium detectors, face significant challenges in detecting HEU when it is shielded by heavy metals. Addressing this critical security need, we introduce an on-site detection method for lead-shielded HEU employing a transportable NDA system that utilizes the 252Cf rotation method with a water Cherenkov neutron detector. This cost-effective NDA system is capable of detecting 4.17 g of 235U within a 12 min measurement period using a 252Cf source of 3.7 MBq. Integrating this system into border control measures can enhance the prevention of HEU proliferation significantly and offer robust deterrence against nuclear terrorism. [ABSTRACT FROM AUTHOR]

Transparent, inorganic composite materials are of broad interest, from structural components in astronomical telescopes and mirror supports to solid-state lasers, smart window devices, and gravitational wave detectors. Despite great progress in material synthesis, it remains a standing challenge to fabricate such transparent glass composites with high crystallinity (HC-TGC). Here, we demonstrate the co-solidification of a mixture of melts with a stark contrast in crystallization habit as an approach for preparing HC-TGC materials. The melts used in this approach are selected so that glass formation and crystal precipitation occur simultaneously and synergistically, avoiding the formation of interfacial cracks, residual pores, and delamination effects. Using this method, various unusual hybridized HC-TGC materials such as oxychloride, oxybromide, and oxyiodide composite systems were fabricated in dense, bulk shapes. These materials exhibit intriguing optical properties and neutron response-ability. Using such HC-TGC materials, we develop a neutron detector and demonstrate the application for efficient neutron monitoring and even single neutron detection. We expect that these findings may help to bring about a generation of fully inorganic, transparent composites with synergistic combinations of conventionally incompatible materials. Transparent composites are significant for various applications. Here, the authors propose the co-solidification strategy of crystal and glass melts for preparing transparent glass composite with high crystallinity and apply for neutron detection. [ABSTRACT FROM AUTHOR]

Nuclear reactions are responsible for the chemical evolution of stars, galaxies and the Universe. Unfortunately, at temperatures of interest for nuclear astrophysics, the cross-sections of the thermonuclear reactions are in the pico- femto-barn range and thus measuring them in the laboratory is extremely challenging. In this framework, major steps forward were made with the advent of underground nuclear astrophysics, pioneered by the Laboratory for Underground Nuclear Astrophysics (LUNA). The cosmic background reduction by several orders of magnitude obtained at LUNA, however, needs to be combined with high-performance detectors and dedicated shieldings to obtain the required sensitivity. In the present paper, we report on the recent and future detector-shielding designs at LUNA. [ABSTRACT FROM AUTHOR]

This work presents GN-Vision, a novel dual γ-ray and neutron imaging system, which aims at simultaneously obtaining information about the spatial origin of γ-ray and neutron sources. The proposed device is based on two position sensitive detection planes and exploits the Compton imaging technique for the imaging of γ-rays. In addition, spatial distributions of slow- and thermal-neutron sources (<100 eV) are reconstructed by using a passive neutron pin-hole collimator attached to the first detection plane. The proposed gamma-neutron imaging device could be of prime interest for nuclear safety and security applications. The two main advantages of this imaging system are its high efficiency and portability, making it well suited for nuclear applications were compactness and real-time imaging is important. This work presents the working principle and conceptual design of the GN-Vision system and explores, on the basis of Monte Carlo simulations, its simultaneous γ-ray and neutron detection and imaging capabilities for a realistic scenario where a 252Cf source is hidden in a neutron moderating container. [ABSTRACT FROM AUTHOR]

Metal halide perovskite materials have received significant attention in recent years due to their promising properties and potential applications, particularly their use as scintillator detectors, which is rapidly emerging due to their promising advantages as detectors, such as low costs, fast response, high quantum yield, strong absorption, scalability, flexibility, and emission wavelength tunability. Given the effectiveness of perovskites as α particle detectors and the potential of 10B as a neutron converter, in this paper a 10B converting layer was coupled with an all-inorganic lead halide perovskite (CsPbBr3) layer aiming to create a thermal neutron detector. Specifically, a 1 µ m thin film of 10B and a 1 µ m thin layer of CsPbBr3 were deposited on a suitable substrate using a laser ablation process. The fabricated detector was subjected to a comprehensive characterization, including structural, morphological, and detection properties. As output, the films exhibit macroscopically uniform behavior and good adhesion to the substrate. In terms of thermal neutron efficiency, an efficiency of (7.9 ± 0.3)% was determined with respect to a commercial detector (EJ-426), which corresponds to an intrinsic efficiency of (2.5 ± 0.1)%. Also, Monte Carlo simulations were conducted, and the optimum value of the 10B layer thickness was found to be 2.5 µ m. [ABSTRACT FROM AUTHOR]

The electronic structure and translucent nature of lithium tetraborate (Li2B4O7) render it promising as a scintillator medium for neutron detection applications. The inherently large neutron capture cross-section due to 10B and 6Li isotopes and the ease with which Li2B4O7 can be enriched with these isotopes, combined with the facile inclusion of rare earth dopants (occupying the Li+ sites), are expected to improve the luminescent properties, as well as the neutron detection efficiency, of Li2B4O7. The electronic structure of both doped and undoped Li2B4O7 were explored, using photoemission and inverse photoemission spectroscopies, optical measurements, and theoretical computational studies such as density functional theory. The scintillation properties are further enhanced because of the wide bandgap, making Li2B4O7 extremely translucent, so that capturing the neutron scintillation output is neither hindered nor diminished. Therefore, in this review, demonstrations of the possible amplification of neutron capture efficiencies, courtesy of rare-earth dopants, along with insights into a significantly large charge production (associated with neutron capture), are presented. [ABSTRACT FROM AUTHOR]

Solar flares are broadly classified as impulsive or gradual. Ions accelerated in a gradual flare are thought to be accelerated through a shock acceleration mechanism, but the particle acceleration process in an impulsive flare is still largely unexplored. To understand the acceleration process, it is necessary to measure the high-energy gamma rays and neutrons produced by the impulsive flare. Under such circumstances, on 7 November 2004, a huge X2.0 flare occurred on the solar surface, where ions were accelerated to energies greater than 10 GeV. The accelerated primary protons collided with the solar atmosphere and produced line gamma rays and neutrons. These particles were received as neutrons and line gamma rays, respectively. Neutrons of a few GeV, on the other hand, decay to produce secondary protons while traveling 0.06 au in the solar–terrestrial space. These secondary protons arrive at the magnetopause. Although the flux of secondary protons is very low, the effect of collecting secondary protons arriving in a wide region of the magnetosphere (the Funnel or Horn effect) has resulted in significant signals being received by the solar neutron telescope at Mt. Sierra Negra (4600 m). This information suggests that ions on the solar surface are accelerated to over 10 GeV with an impulsive flare. [ABSTRACT FROM AUTHOR]

Pure CaF 2 crystals have been widely used for optical functional crystals due to their good optical properties, mechanical properties, and chemical stability. This study discovered the crystal's pulse shape discrimination (PSD), proving it a promising scintillator for fast neutron detection via the 40Ca neutron capture reaction. Luminescence emission spectra were studied by X-ray luminescence measurements. The maximum emission peak was observed between 250 and 300 nm, corresponding to self-trap exciton emission. The crystal response to gamma, alpha, and neutron were studied under 137Cs, 241Am, and 252Cf radiation sources, respectively. The difference in gamma and alpha decay times enabled the PSD capability of pure CaF 2. Large neutron reaction cross-sections, PSD capability, and good chemical stability make pure CaF 2 crystal candidates for fast neutron beam monitoring detectors. Moreover, the crystal can be used for 40Ca(n,p)40K and 40Ca(n,α)37Ag neutron capture cross-section study. • The paper reports the first study of pure CaF 2 crystal for fast neutron detection. • Light yield of the crystal is 7100 ± 700 photons/MeV. • The crystal has good linearity response, energy resolution is about 9.1% at 662 keV. • PSD was studied for gamma-alpha (FOM = 0.85) and gamma-neutron (FOM = 0.80) separation. [ABSTRACT FROM AUTHOR]

Measurement of the space neutron radiation environment has put forward new requirements for the miniaturization and lightweight design of neutron spectrometers. In this paper, a compact broad-spectrum neutron spectrometer was designed, in which the fast neutron detector was based on the EJ-254 scintillator-coupled with SiPMs array, and the thermal and epithermal neutron detectors were based on the NaI(Tl + Li) (NaIL) scintillator coupled with SiPMs array encapsulated in Al and Cd shells, respectively. The overall weight of the neutron spectrometer was only 2.4 kg, and its dimensions were 154 mm × 123 mm × 115 mm. The fast neutron energy spectrum was obtained based on the capture-gated method and the Maximum Likelihood Expectation Maximization (MLEM) unfolding algorithm; the counts of thermal and epithermal neutrons were obtained based on the optimized frequency-domain Pulse Shape Discrimination (PSD) method and cadmium difference method. The proposed neutron spectrometer with all applied methods was tested as a whole system with a252Cf and a241Am–Be source. The spectrum result was compared to an ISO standard source. The accuracy of fast part of 0.5–10 MeV was 5.9% in definition of Relative Root Mean Squared Error (RRMSE). The thermal and epithermal neutron counts were far higher than standard spectrum, and we proved it being effected by laboratory introduced neutron scattering through a simulation, thus the thermal and epithermal flux measurements was believed to be decent. The Figure of Merit (FoM) of the NaIL's PSD neutron gamma discrimination were 2.57 and 2.90 respectively. [ABSTRACT FROM AUTHOR]

The prototype of a TDC board has been developed for the new high granular time-of-flight neutron detector (HGND). The board is based on the standard LVDS 4x asynchronous oversampling using the xc7k160 FPGA with a 100 ps bin width. The HGND is being developed for the BM@N (Baryonic Matter at Nuclotron) experiment to identify neutrons and to measure their energies in heavy-ion collisions at ion beam energies up to 4 A GeV. The HGND consists of about 2000 scintillator detectors (cells) with a size of 40 × 40 × 25 mm 3 and light readout with EQR15 11-6060D-S photodetectors. To measure the time resolution of the scintillator cells, the two-channel FPGA TDC board prototype with two scintillator cells was tested with an electron beam of "Pakhra" synchrotron at the LPI institute (Moscow, Russia). The measured cell time resolution is 146 ps, which is in a good agreement with the 142 ps time resolution measured with a 12-bit @ 5 GS/s CAEN DT5742 digitizer. For the full HGND, the TDC readout board with three such FPGAs will read 250 channels. In total, eight such TDC boards will be used for the full HGND at the BM@N experiment. [ABSTRACT FROM AUTHOR]

Cs 2 LiYCl 6 :Ce crystal scintillator (CLYC:Ce) has garnered significant attention for its applications in both neutron detection and gamma-ray spectroscopy. This is due to its excellent pulse shape discrimination (PSD) capabilities, which allow for distinguishing between neutrons and gamma rays. Recently, there has been interest in utilizing CLYC:Ce in high-dose environments, making it crucial to understand the effects of radiation damage on its performance. In this work, we aim to examine the impact of radiation damage on the scintillation performance of CLYC:Ce under 100 MeV proton beam. To minimize systematic uncertainty, the change in light output of CLYC:Ce was measured at different accumulated doses using the same experimental setup. The pulse shape discrimination for thermal neutrons was assessed before and after irradiation. Additionally, the decay time of gamma-ray and thermal neutron-induced pulses was analyzed at various accumulated doses. The results of these analyses provide support for little degradation of pulse shape discrimination even with the high proton dose. Furthermore, the study considered and discussed the scintillation recovery of CLYC:Ce over a month. Despite the substantial damage induced by high-energy protons, the results demonstrate that CLYC:Ce remains a promising scintillator for thermal neutron detection. • The scintillation performance of Cs 2 LiYCl 6 :Ce crystal was investigated under the proton-induced radiation damage up to 867 ± 87 rad. • The light output was measured considering minimizing the systematic uncertainty. • The light output and energy resolution significantly decreased at 867 ± 87 rad and slightly improved after a 30-day recovery. • The thermal neutron and background gamma pulse shape discrimination did not decrease after proton-induced damage. • Cs 2 LiYCl 6 :Ce is an excellent crystal scintillator for thermal neutron detection even up to 867 ± 87 rad proton dose. [ABSTRACT FROM AUTHOR]