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The research team has developed new plastic scintillators in the form of microspheres, called PSm, by combining styrene, 9-vinylcarbazole (VK), and 4-vinylbenzyl chloride (VBC). The primary objective of this study was to explore the feasibility of incorporating the fluorescent solute (VK) into the polymer structure to prevent its leaching out when PSm are utilized in liquid flow through detection systems or organic solvents. The secondary aim was to examine the impact of adding the chlorine functional group to the scintillation polymer, with the intention of replacing it with an extractant in the future to create covalently linked PSresins. The findings of the study reveal that the homopolymer of polyvinylcarbazole (PVK) performs poorly while used as a unitary scintillator system for plastic scintillation measurements. However, the incorporation of monomers in the form of copolymers with styrene has a more significant impact on scintillation properties compared to the mixture of homopolymers. In the case of 9-vinylcarbazole (VK), its presence at a weight proportion of 10% leads to an increase in scintillation efficiencies, although it is still inferior to the classical PS. Conversely, the situation is different for 4-vinylbenzyl chloride (VBC), where the chlorine in the copolymer results in higher quenching, and the polymer is also less resistant to organic solvents due to the formation of short polymer chains. For VBC, the mixture of polymers yields better results and enables the production of covalently linked PSresins. [Display omitted] • Vinylcarbazole may act as fluor for scintillation if copolymerized with styrene in a 10% proportion. • P(ST-VBC) scintillating copolymers are highly affected by quenching. • P(ST-VBC) copolymers are structurally weak and become dissolve in methanol. • Cl-moiety can be included in scintillators by mixing PS and PVBC. [ABSTRACT FROM AUTHOR]

In this study, we investigate the impact of zenith angle variations on cosmic-ray induced background in High-Purity Germanium (HPGe) gamma spectrometers using a coincidence technique based on plastic scintillator-Germanium detectors. We utilize an HPGe detector (Model GC2018 Mirion Ge Detector) enclosed within a low-activity cylindrical lead shield (Model 747E Mirion Lead Shield). For cosmic ray detection, a coincidence detection system with plastic scintillator detectors was positioned on top of the lead shielding. The zenith angle at the Germanium detector is computed using the dimensions of the square plastic scintillator and its distance from the Germanium detector center. We carried out measurements of cosmic-ray induced background in an HPGe gamma spectrometer with a square plastic configuration (80cm x 80cm), equivalent to a 45° zenith angle. The experimental measurements were compared with GEANT4 simulation data. The results demonstrate a good agreement between the measured energy spectrum and the simulated data across the energy range of 0.05 to 47 MeV. Further investigations into the effects of varying zenith angles provide valuable insights for optimizing HPGe spectrometer setups with minimized background interference. • The energy response of the cosmic-ray induced background in a HPGe gamma spectrometer from 0.05 to 47 MeV. • Explores cosmic-ray induced background varies with zenith angles of 14°; 27°; 45°; 52°; 90°. • Shows variation proportional to the total background with changes in angle. [ABSTRACT FROM AUTHOR]

[Display omitted] • B-site co-doped perovskite nanocrystals were synthesized. • Co-doped NCs has excellent photoluminescence efficiency and lifetime. • The mechanism of enhanced luminescence of co-doped NCs was elucidated. • The stable scintillator film was prepared by PVDF-HFP encapsulation of co-doped NCs. • The film has excellent performance as scintillator under X-ray. Perovskite scintillators with low cost, easy preparation, environmental stability, and high-resolution have become candidates for X-ray imaging applications. Here, based on the calculation results of surface formation energy (E f) and vacancy defect energy (E vac), a series of co-doped perovskite nanocrystals (NCs) with photoluminescence high quantum yield (PLQY) and fast luminescence decay time had been prepared by doping several bivalent metal ions into the B-site of methylammonium lead tribromide (MAPbBr 3). In addition, the scintillator with flexibility was prepared using poly(vinylidene fluoride-hexafluoropropylene) (PVDF-HFP) as the carrier, showing excellent stability and scintillation performance, with a light yield of 21,200 photons/MeV, imaging resolution reached 11.7 lp/mm, and low detection limits of 462 nGy air s−1. Finally, we demonstrated the scintillator characteristic with high-quality imaging results and excellent tolerance under high dose rate X-ray (25 mGy s−1). Therefore, the combination of co-doped nanocrystals with excellent optical properties and PVDF-HFP further paves the way for the development of a scintillator. [ABSTRACT FROM AUTHOR]

We propose a novel approach based on variational autoencoder with Gaussian mixture latent space (GMVAE) to address the challenging problem of pulse shape discrimination (PSD) in organic scintillators, in the presence of pile up. Unlike deterministic charge integration, which is very sensitive to pulse-processing parameters, the GMVAE performances are robust against variations of the hyperparameters. When compared to other supervised machine learning methods, GMVAE requires the fewest training pulses (100) to achieve a classification accuracy within 2% of its optimum performance, i.e. , 98.3% accuracy. GMVAE exhibited excellent classification despite the difference in energy spectra between the training and test data sets, which were 14.1 MeV neutron pulses and 239PuBe pulses, respectively. While requiring minimum supervision, GMVAE showed superior PSD performances compared to both deterministic and supervised machine learning approaches. GMVAE is hence particularly suitable for real-time pulse classification, where expert labeling is unavailable and fine tuning of the discrimination parameters impractical. • A variational autoencoder with Gaussian mixture prior for pulse shape discrimination with pile ups. • Our method outperforms deterministic and ML methods with minimal supervision. • Our GMVAE required only 100 training pulses to achieve near-optimal accuracy. • Proved GMVAE's adaptability to different energy spectra between training and testing. • Potential of GMVAE for real-time applications due to its computational efficiency. [ABSTRACT FROM AUTHOR]

Driven by the pursuit of optimizing the luminescent properties of garnet-based single crystals for X-ray imaging applications, this work reports on the successful synthesis and in-depth characterization of GYAGG crystals doped with Ce³⁺ or Tb³⁺ ions, and doubly-doped with both of them. Micro-pulling down synthesis yielded crystals with a single cubic phase confirmed by X-ray diffraction. Photoluminescence (PL) and radioluminescence (RL) measurements on Ce³⁺,Tb³⁺ co-doped GYAGG revealed bidirectional energy transfer processes. Characteristic broadband 5d 1 →4f emission of Ce³⁺ centers peaking at 530 nm and narrow 4f→4f emission lines of Tb³⁺ ions starting from 5D 4 level within 480–630 nm were observed. At higher doping levels, cross-relaxation in Tb³⁺ pairs resulted depleted 5D 3 state and only the emission from 5D 4 one was observed in the spectra. Analysis of PL decay characteristics corroborated the spectral observations, confirming progressively decreasing Ce³⁺ decay time (down to 40 ns at 15 % Tb3+) due to enhanced Ce³⁺→Tb³⁺ energy transfer. Similarly, the Tb³⁺ decay time accelerated by more than 60 % after the Ce³⁺ co-doping. Notably, co-doping with 0.5 % Ce³⁺ and 10–15 % Tb³⁺ doubled the luminescence intensity of RL spectra compared to 0.5 % Ce³⁺-doping alone, attributed to the increased density of emitting centers. • High-quality and crack-free GYAGG:Ce,Tb single crystals were successfully grown. • The photoluminescence spectra revealed Ce³⁺↔Tb³⁺ bidirectional energy transfer. • At lower Tb³⁺ doping (0.5 %), the bidirectional energy transfer was inefficient. • High Tb³⁺ doping (15 %) significantly enhanced energy transfer. • Co-doping yielded a two-fold radioluminescence intensity compared to sole doping. [ABSTRACT FROM AUTHOR]

In this study, we examine the impact of optical and scintillation properties on needle-shaped bis(butylammonium) lead bromide [(BA) 2 PbBr 4 ] crystals (average length of 12.7 mm and average width of 1.3 mm), considering different growth methods and dimensions. Needle-shaped crystals with a length-to-width aspect ratio greater than 10 are essential for cutting-edge radiation imaging technology. Through X-ray diffraction characterization, we observe lattice expansion in the needle-shaped crystals compared to previous single crystals. This expansion leads to a stronger overlap between absorption and photoluminescence (PL) spectra, resulting in a smaller Stokes shift of 26 meV. Time-resolved PL analysis reveals a fast decay component of 0.8 ns, which is 68 % faster than the previously reported best value of 2.0 ns, with an average decay time of 3.6 ns, 48 % faster than the best reported value of 7.0 ns. Although our measured sample exhibits a comparatively low light yield (LY) of 7.8 ph/keV due to strong self-absorption, the best energy resolution is observed with a value of 11.5 %, similar to the best reported value of 10.9 %. Despite this, the LY is notably superior to that of previously reported benzylammonium lead bromide [(BZA) 2 PbBr 4 ] crystals (3.7 ph/keV). Additionally, scintillation decay shows a fast component of 9.4 ns and an average decay time of 119 ns. These characteristics make two-dimensional-(BA) 2 PbBr 4 needle-shaped crystals promising candidates for cost-effective and scalable applications in radiation imaging technology. • Solution process 2D-(BA) 2 PbBr 4 needle-shaped crystals was successfully synthesized with an aspect ratio of length to width exceeding 10. • Time-resolved photoluminescence analysis reveals ultra-fast decay component of 0.8 ns, which is 68 % faster than the reported value of 2.0 ns. • Solution grown needle-shaped 2D perovskites are an interesting and versatile class of materials for cost-effective and scalable in cutting-edge radiation imaging technology. [ABSTRACT FROM AUTHOR]

The aim of the LHCb Upgrade II is to operate at a luminosity of up to 1. 5 × 1 0 34 cm 2 s−1 to collect a data set of 300 fb−1. The required substantial modifications of the current LHCb electromagnetic calorimeter due to high radiation doses in the central region and increased particle densities are referred to as PicoCal. Modification of the ECAL already during Long Shutdown 3 (LS3) will reduce the occupancy and mitigate substantial ageing effects in the central region after Run 3. Several scintillating sampling ECAL technologies are currently being investigated in an ongoing R&D campaign: Spaghetti Calorimeter (SpaCal) with garnet scintillating crystals and tungsten absorber, SpaCal with scintillating plastic fibres and tungsten or lead absorber, and Shashlik with polystyrene tiles, lead absorber and fast WLS-fibres. Timing capabilities with tens of picoseconds precision and increased granularity with denser absorber in the central region are needed for pile-up mitigation. Time resolutions of better than 20 ps at high energy were observed in test beam measurements of SpaCal and Shashlik prototype modules. [ABSTRACT FROM AUTHOR]

The distribution of neutrons and gamma-rays in mixed fields is a main interest in pulse shape discrimination (PSD) studies, and becomes more significant when it involves techniques such as machine learning which requires true data. One of the surest methods to label neutrons and gamma-rays is neutron Time-of-Flight. This can be applied to the identification of special nuclear materials and by extension to nuclear non-proliferation. Moreover, the integration of silicon photomultiplier (SiPM) technology can make the neutron Time-of-Flight system more compact. Two EJ-276 plastic scintillators, which are capable of PSD, were coupled to SiPMs. The actual portion of neutrons from a 252Cf source intruding the gamma-rays in PSD ratio distribution, labeled by neutron Time-of-Flight, was calculated and then compared with gamma-rejection ratio (GRR) for each threshold in SiPM-based pulse shape discrimination. [ABSTRACT FROM AUTHOR]

In Particle and Nuclear Physics research and related applications, organic scintillators provide a cost-effective technology for the detection of ionising radiation. The next generation of experiments in this field is driving fundamental research and development on these materials, demanding improved light yield, radiation hardness, and fast response. Common materials such as PEN and PET have been found to offer scintillation properties competitive to commercial alternatives without the use of dopants. Motivated by their complementarity in terms of light yield, radiation hardness, and time response, there is an increasing interest in investigating PET:PEN mixtures to ascertain whether they exhibit synergistic blending. This paper presents results from the systematic development of samples of PET, PEN, and PET:PEN blends with varied mass proportions. The manufacturing technique, involving injection moulding of granule raw material, is detailed. The effects of doping the polymer base substrate with fluorescent dopants are explored. Finally, the emission spectra of the different material compositions and their relative light output are presented. • We studied the scintillation properties of scintillators based on PET and PEN. • We established an injection-moulding technique for the production of small scintillators. • We produced scintillator samples of PET:PEN blends with varied mass proportion. • The scintillation output increases with the mass proportion of PEN. • The addition of wavelength-shifting fluors (POPOP and BBOT) increases scintillation. [ABSTRACT FROM AUTHOR]

Helium-4-based scintillation detector technology is emerging as a strong alternative to pulse-shape discrimination-capable organic scintillators for fast neutron detection and spectroscopy, particularly in extreme gamma-ray environments. The 4 He detector is intrinsically insensitive to gamma radiation, as it has a relatively low cross-section for gamma-ray interactions, and the stopping power of electrons in the 4He medium is low compared to that of 4 He recoil nuclei. Consequently, gamma rays can be discriminated by simple energy deposition thresholding instead of the more complex pulse shape analysis. The energy resolution of 4 He scintillation detectors has not yet been well-characterized over a broad range of energy depositions, which limits the ability to deconvolve the source spectra. In this work, an experiment was performed to characterize the response of an Arktis S670 4 He detector to nuclear recoils up to 9 MeV. The 4 He detector was positioned in the center of a semicircular array of organic scintillation detectors operated in coincidence. Deuterium–deuterium and deuterium–tritium neutron generators provided monoenergetic neutrons, yielding geometrically constrained nuclear recoils ranging from 0.0925 to 8.87 MeV. The detector response provides evidence for scintillation linearity beyond the previously reported energy range. The measured response was used to develop an energy resolution function applicable to this energy range for use in high-fidelity detector simulations needed by future applications. [ABSTRACT FROM AUTHOR]

A new experimental method to measure muon polarization using a scintillating material has been proposed. One of the key issues for this measurement is the choice of scintillation materials which can maintain the μ + spin polarization for several μ + lifetimes. Thus far, a CeF 3 scintillating crystal has been known to be only a possible candidate and it is highly preferable to find other scintillators whose performance is nearly equivalent to CeF 3. The residual μ + polarization in a 2% cerium-doped LaF 3 scintillating crystal was measured at the J-PARC Material and Life Science Facility (MLF) by applying the longitudinal field (LF) to the LaF 3 material. The polarization was obtained to be 83 and 87 % with LF = 100 and 140 Gauss, respectively, which is high enough to measure the μ + polarization in various experiments. [ABSTRACT FROM AUTHOR]

We evaluated the performance of a SONY CMOS sensor, IU233N5-Z with a very small pixel size of 1. 12 μ m and 1 million pixels, for imaging X-rays, α and β rays. The energy resolution of X-rays was 180 eV at 5.9 keV and 184 eV at 6.5 keV when irradiating the CMOS sensor with 55Fe, and 344 eV at 14.4 keV when irradiating the CMOS sensor with 57Co, which is similar to that of the CCD detector even at room temperature. Furthermore, We read out the optical light of a CsI(Tl) scintillator by this CMOS detector and obtained a detection efficiency of ∼ 5%. [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]

In this study, the interaction cross sections of heavy oxide scintillators, which have a very important place in high energy physics research, with photon and particle radiation were comparatively investigated. In this context, the interaction parameters of six different Ce-doped heavy oxide scintillators were obtained using updated software. The interactions of photons with energies between 1 keV and 100 GeV with scintillators were evaluated in the light of the results produced by the Phy-X/PSD software. In addition to the continuous energy range, calculations were also made on the photon energies emitted with the highest probability of emission from sources 241Am (59.54 keV), 133Ba (356 keV), 22Na (511 and 1280 keV), 137Cs (662 keV) and 152Eu (1460 keV). Additionally, evaluations of energy absorption build-up factors valid under broad beam conditions are also included in this study. Fast neutron absorption cross sections and changes in the range (R) values for heavy particle radiation in the range of 1 keV–20 MeV were also determined with SRIM and ESTAR software. All data obtained depending on energy are explained according to the mass percentages of Lu, Gd, Hf, Y, Al and O elements in the scintillators. The highest interaction cross section for photons was obtained in the Lu 2 Gd 2 SiO 5 (Ce 0.3%) scintillator (HOS2). The interaction cross section of this scintillator was obtained as 3.115 and 0.042 cm2/g at 0.1 MeV and 10 MeV photon energies, respectively. On the other hand, the highest cross-sections of the fast neutrons were observed in the scintillator (HOS5) containing GdAlO 3 (Ce 1.0%) as 0.148 cm−1. This difference in neutron radiation has been explained by calculating the individual attenuation abilities of the elements in the structures. It is hoped that the data obtained will guide researchers working on the detection of different types of radiation. [ABSTRACT FROM AUTHOR]

A Cs 2 LiYCl 6 (CLYC) scintillation crystal is a promising candidate for fast neutron spectroscopy due to its dual mode gamma/neutron capability and good energy resolution. Despite promising features, CLYC's limited radiation tolerance and inability to separate alpha/proton particles using pulse shape discrimination (PSD) method restrict its applicability in fast neutron spectroscopy. The significant cross-sections for 35Cl(n,p)35S and 35Cl(n, α)32P reactions make 35Cl-containing crystals attractive candidates for fast neutron detection, prompting their development as a promising new solution. This study reports the growth of LaCl 3 crystals via the Bridgman technique, enabling further exploration of their scintillation and material properties for fast neutron detection applications. The effects of the proton irradiation on LaCl 3 crystals were investigated by irradiating them with a 100 MeV proton beam at the Korea Multi-purpose Accelerator Complex. The study quantified radiation damage by comparing the pre- and post-irradiation scintillation properties and PSD of the LaCl 3 crystals. The results of the measurements demonstrate that LaCl 3 crystals are promising candidates for applications in fast neutron identification, spectroscopy, and space mission, maintaining performance even under high-radiation environments. • Good alpha/proton separation capability of undoped LaCl 3 crystals. • We successfully grew undoped LaCl 3 crystals up to a size of 38 Φ mm x 25 mm. • Scintillation properties of the crystals showed good agreement with published values. • Direct unfolding method was achieved for fast neutron measurements. • Radiation hardness of LaCl 3 crystals was confirmed. [ABSTRACT FROM AUTHOR]

In this study, we present the development of a phoswich detector system employing a Bismuth Germanate (BGO) crystal scintillator in combination with a Polyethylene naphthalate (PEN) film plastic scintillator. Phoswich detectors can contribute to various applications, including radiation monitoring, medical imaging, and nuclear physics experiments, due to their ability to discriminate between different types of radiation. The thin PEN film is sensitive to α and β radiation, while the BGO scintillator exhibits good γ radiation detection efficiency. The incident radiation type and its energy can be determined by analyzing the difference in decay times between these two scintillators. This paper presents an analysis of the detector's response to α , β , and γ radiation, and the particle tagging efficiencies are to be over 99.9%, 92%, and 99.8%, respectively. • We observe effective discrimination based on alpha, beta, and gamma characteristics. • The signals from BGO and PEN film fit well through pulse shape discrimination. • The tagging efficiency for alpha, beta, and gamma are over 99.9%, 92%, and 99.8%. [ABSTRACT FROM AUTHOR]

Tb3+ doped sodium-gadolinium-aluminum-phosphate glass samples (PGNA) with chemical compositions 30Na 2 CO 3 :8Gd 2 O 3 :5Al 2 O 3: (57- x)P 2 O 5 : x Tb 4 O 7 (where x = 0 , 0.25, 0.5, 1.0, 2.0, 3.0, 4.0, and 5 mol. %) were manufactured by using adopting the conventional melt quenching technique. The PXRD study of the prepared samples was used to confirm the amorphous structure. FE-SEM, EDS, and FTIR studies were carried out to analyze the elemental and structural characteristics of synthesized glasses. The X-ray induced luminescence spectra were obtained at room temperature and the emission peak at 311 nm corresponding to Gd3+ transition was observed decreasing with the increase of Tb 4 O 7 concentrations, while emission peak intensities corresponding to Tb3+ electronic transitions increased with the concentrations of Tb 4 O 7. The results from the photoluminescence (PL) studies in the UV–Vis–NIR region showed the glasses emitting intense green light with the highest peak at 544 nm under excitations at 220, 272, and 311 nm. The PL emission intensities were found reasonably high under characteristic excitations of both Gd3+ and Tb3+, peaking at 380, 414, 437, 489, 544, 584, and 623 nm, which corresponding to 5D 3 → 7F 6, 5D 3 → 7F 5 , 5D 3 → 7F 4 , 5D 4 → 7F 6 , 5D 4 → 7F 5 , 5D 4 → 7F 5 , 5D 4 → 7F 4 , 5D 4 → 7F 3 transitions, respectively. The decay time of Tb3+ ions has been observed to decrease when the concentration of Tb 4 O 7 increases. The energy transfer from Gd3+ to Tb3+ was found increased with increasing of Tb3+ concentrations. The CIE 1931 chromaticity coordinates of Tb doped PGNA glasses were found to be in the green range, indicating a strong potential for green laser application. The results from X-ray imaging showed that Tb-doped glass scintillators promise of efficient and low-cost solution for X-ray imaging applications. • XRL spectra has the emission peak at 311 nm corresponding to 6P 7/2 → 8S 7/2 due to Gd3+ ion in the host. • Glasses emitting intense green light with highest peak at 544 nm under 220, 272, 311 nm excitations. • PL emission intensities found reasonably high for both Gd3+ and Tb3+ characteristic excitation. • CIE 1931 coordinates of glasses found in the green indentify potential for green laser application. • The Tb-doped glass promise of efficient and low-cost solution for X-ray imaging applications. [ABSTRACT FROM AUTHOR]

In this study, we investigated the radiation hardness of phosphate glasses doped with terbium (Tb) ions, having the composition 56 P 2 O 5 : 30 Na 2 CO 3 : 5 Al 2 O 3 : 8 Gd 2 O 3 : 1 Tb 4 O 7 , under proton and X-ray beam excitation. These glasses were synthesized using the melt and quench method. The dose distribution inside the volume of these samples was studied, and the absolute absorbed dose was calculated. The scintillation and optical properties, such as photoluminescence, transmission, absorption, etc., were studied and compared before and after exposure to irradiation. Under both types of irradiation, we observed two major emission peaks corresponding to the transitions 5 D 3 → 7 F 5 (at 480 – 510 nm, in the blue region) and 5 D 4 → 7 F 6 (at 535 – 565 nm, in the green region). The dominant green emission is attributed to the presence of Tb 3 + dopants. Notably, after X-ray irradiation, we observed a change in the sample's color, accompanied by a decrease in the intensity of all peaks. This suggests a potential limitation in the radiation hardness of Tb-doped phosphate glass. Similarly we checked the luminous intensity with 100 MeV proton beam. Furthermore, we conducted thermal annealing process to explore the possibility of radiation damage recovery and found out that sample does recover, its intensity recovered and its color change back to transparent from yellowish color. Our results highlight characteristics of Tb-doped phosphate glasses, which make them valuable for diverse applications such as radiation detection, dosimetry, radiography, biomedical imaging, and related fields. • Tb-doped phosphate glasses were prepared using the melt and quench method. • The sample was irradiated with X-rays and a 100 MeV proton beam. • At an absorbed dose of 90 Gy from X-rays, the sample changed to a yellowish color. • X-ray-damaged sample exhibited lower transmission compared to fresh sample. • Annealing restored X-ray-damaged sample to levels comparable with fresh samples. [ABSTRACT FROM AUTHOR]

Intensity-modulated delivery techniques in radiotherapy are advanced methods that use the superposition of small fields to create complex dose distributions. These techniques result in intense gradients and inhomogeneous dose regions, making the dosimetry of composite fields challenging, especially when the sub-fields superposition does not restore charged particle equilibrium. This work aims to address the response of radiation detectors in non-equilibrium conditions. Two ionization chambers and a micro-diamond detector were irradiated using composite fields from VMAT plans with spherical targets with diameters ranging from 0.5 to 8 cm. The radiation detectors' response and the dose delivered by the VMAT plans were measured using a plastic scintillator detector and radiochromic film as reference detectors. It was observed that an under-response of the ionization chambers was up to 13% and an over-response of the micro-diamond detector was up to 2.5%. Additionally, output correction factors were derived and used to measure the absorbed dose in composite plans using the radiation detectors. The measured dose was compared with that measured with radiochromic film. A dose difference was found within radiochromic film uncertainties (<2.5%). The results of this work suggest that radiation detectors require output correction factors when non-equilibrium conditions persist in composite fields. However, a link between static and composite fields could not be established because the field size cannot be determined accurately. • A plastic scintillation detector was utilized to evaluate detector response. • The ionization chambers showed an under-response of up to 13%. • The micro-diamond detector showed an over-response of up to 2.5%. • Output correction factors were determined for the radiation detectors. • The corrected dose showed differences less than 2% compared to radiochromic film. [ABSTRACT FROM AUTHOR]

The pulse-by-pulse characteristics of electron beams from a clinical linear accelerator (linac) at high dose rates are crucial for ensuring precise dose delivery in radiation therapy. In this research, we employ a radioluminescence scintillator made from Ge-doped silica optical fiber to analyse electron beams at standard therapy dose rates 600 cGy/min with energy of 15 MeV. The scintillator is combined with a photomultiplier tube (PMT) and a photon-counting setup to achieve microsecond (μs) gating times, providing high temporal resolution. For sub-microsecond (sub-μs) temporal resolution, we utilize a multi-pixel photon counter and a rapid digital oscilloscope. Our study examines the peak time and the time it takes for pulses to return to baseline, uncovering the effects of afterglow at elevated dose rates and its potential implications for dosimetry precision. Our results indicate that monitor chambers, which have lower temporal resolution than the radioluminescence system outlined in this study, may struggle to accurately track high-rate dose delivery, emphasizing the necessity for advanced monitoring methods in FLASH radiotherapy. The dosimetric data was further analysed for deeper analytics on a cloud-based system. The dosimetric data underwent advanced analysis on a cloud-based platform, employing a prototype analytics software system comprised of Dosi-Client and Dosi-Cloud Backend components for real-time data acquisition and processing. This innovative approach revealed significant insights into radiation dosimetry, including the detection of anomalies through a reconstruction convolutional autoencoder, enhancing the precision and reliability of dosimetric measurements. • Introduces a radioluminescence optical fiber-based dosimetry system. • It is designed for real-time detection of dose-rate errors. • Ge-doped silica optical fiber scintillator showed successful measurements. • An embedded computer is used for measurement and storage of dosimetry data. • Cloud system provides storage and analysis of the data. [ABSTRACT FROM AUTHOR]

Measurements of naturally occurring concentrations of 40K, and of the decay series of 238U and 232Th, are of interest in the earth sciences in general, and in particular, scintillator-based gamma spectrometers can be used for the low cost determination of burial dose rates in natural geological samples. We are currently developing a robust, portable, wireless detector specifically intended for field measurement of natural radionuclide concentrations and hence, the calculation of dose rates. One of the challenges in developing and applying such an instrument is reliable calibration. Most calibrations of field instruments depend on access to non-finite matrices of known K, U, Th activity concentrations, in either a 4π or 2π geometry; these are only available at a few facilities around the world. Here we investigate an alternative approach, based on the measurement of small samples containing well-known activity concentrations of only K or U or Th, and Monte-Carlo radiation transport modelling to convert the observed spectra into those expected from specific activity concentrations in a non-finite 4π geometry. We first validate our modelling procedure by simulating these observed spectra. The non-finite matrix calibration spectra are then predicted, and least-squares fitted to the spectrum observed at the centre of a 1 m3 of granite chips; the resulting predicted U, Th and K activity concentrations are compared with independently known values. • Challenging calibration of field instruments for natural radionuclide measurement. • Alternative calibration based on measurement of small samples and MCNP simulations. • Encouraging agreement with measurement gives confidence in the approach. • Methodology allows parametric studies on soil water content or composition. [ABSTRACT FROM AUTHOR]

• β-Ga 2 O 3 –Al 2 O 3 transparent thick films were synthesized using MOCVD. • High scintillation light yield of 5400 ph/5.5 MeV was superior to single crystal. • CVD proved advantageous for rapid synthesis of Ga 2 O 3 -based scintillation screens. β-gallia (β-Ga 2 O 3) has been investigated for adoption in power semiconductor wafers; however, it is a promising scintillating material for X-ray detection screens. Thus, the research on methods for growing β-gallia crystals has attracted considerable attention. Herein, 15-μm thick Ga 2 O 3 –Al 2 O 3 solid solution films with β-gallia structure were synthesized using metal–organic chemical vapor deposition (CVD) at deposition rate of 15 μm h−1. A high scintillation light yield of 5400 photons per 5.5 MeV and a fast decay response of 5.1 ns of the produced films were observed, which were comparable or superior to those of the β-Ga 2 O 3 single crystals. CVD method proved advantageous for the rapid synthesis of micrometer-thick Ga 2 O 3 -based scintillation screens. [ABSTRACT FROM AUTHOR]

[Display omitted] • Organic cuprous clusters were synthesized by antisolvent vapor-assisted crystallization. • Photoluminescence was tunable by adjusting ratio of raw materials due to vacancy defects changing. • Two charge transfer paths exist in the IPPCuI 2. • Superior X-ray scintillation performances exhibit in DR and CT. • Single-component WLED based on IPPCuI 2 has high CRI and stability. Low-dimensional cuprous clusters demonstrate fascinating luminescent properties due to their uniquely diversified charge transfer excited states, which imply it could be ideal candidate for multifunctional applications, such as X-ray scintillators and white light emitting diodes (WLED). However, it is still challenge for low-dimensional cuprous clusters that how to regulate the emission performance to meet the requirements of the specific applications. In this work, we prepared a series of luminescent organic cuprous iodide clusters, (IPP)CuI 2 and (IPP) 2 CuI 3 , which show tunable emission property by simply component regulation. The (IPP)CuI 2 with IPP: CuI = 1: 0.75 show the best scintillator property with super-low detection limit of 62.29 nGy/s and high light yields of 75793.83 photons/MeV which is far beyond most organic copper halide scintillators. A series of clear digital radiography (DR) with high spatial resolution of 10.2 lp/mm and a reconstructed 3D model based on computed tomography (CT) were successfully obtained by the prepared scintillation screen. Moreover, the single-component WLED based on accurately component regulation (IPP)CuI 2 with IPP: CuI = 1: 0.99 exhibits pure white emission with a high CRI (color rendering index) of 82. The luminescence mechanism of charge transfer excited states in tunable emission (IPP)CuI 2 was also investigated. Our works not only provide a kind of ideal materials applied for high-performance single-component WLED and scintillator but also reveal the large potential of low-dimensional organic cuprous halides as luminescent material for multifunctional applications. [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]

• TGFs have possible adverse effects on commercial and general aviation avionics. • A scalable aircraft-based energetic radiation detection system is presented. • Preliminary results include 180 h of aircraft-based measurements. • Developed algorithms for large-scale study of energetic radiation from thunderstorms. Thunderstorm and lightning related energetic radiation can generally be categorized as (1) leader X-rays, (2) Terrestrial Gamma-ray Flashes (TGFs), or (3) Thunderstorm Ground Enhancements (TGEs). TGFs are usually recorded from satellites, and, on some occasions, they have been recorded from the ground, but only a few attempts have been made to measure TGFs from aircraft. Thunderstorm Ground Enhancements (TGEs) are much longer duration than TGFs, and they are recorded at ground level. Energetic radiation associated with thunderstorms and lightning is a relatively recently recognized hazard. It can have possible adverse effects on commercial and general aviation avionics, thus an experimental understanding of the impulsive and prolonged radiation enhancements onboard aircraft is essential (Eack et al., 1996). In this paper, we present artificial TGFs and TGEs, which were acquired in the lab with a compact CsI scintillator detector, along with commercial and general aviation aircraft-based measurements to assess the feasibility of a large-scale aircraft-based study. Our preliminary results include 180 h of aircraft-based measurements, the longest aircraft-based TGF search to date, and show that the detector hardware, installation protocol, processing software, and search algorithm can be used for a large-scale study of energetic radiation from thunderstorms and lightning. [ABSTRACT FROM AUTHOR]

Neutron spectrometry plays a crucial role in decommissioning of nuclear sites and in ensuring the safety of workers from radiation exposure. In this study, we associate a proton recoil spectrometer made by a homemade plastic scintillator with triple discrimination capabilities (fast neutrons, thermal neutrons, and gamma rays) with deconvolution methods to obtain accurate measurements of neutron spectra. The purpose of this work is to test and evaluate the performance of three distinct deconvolution codes, namely MAXED (Maximum Entropy Deconvolution), GRAVEL, and MLEM (Maximum Likelihood Expectation Maximization), using two types of input spectra (flat and Watt spectrum). These deconvolution codes are applied to simulated data using the reference MCNP6.2 Monte Carlo code. Comparing the calculated mean squared error (MSE) performed by the three unfolding methods, we find that MLEM seems to perform better than MAXED and GRAVEL. Furthermore, given the calculated MSE values, the unfolded spectrum of Cf-252 is in better agreement with the standard reference spectrum by using Watt spectrum as input spectrum (MSE<1.2 × 10−6) than using a flat spectrum (MSE<1.3 × 10−6). • The performance of three unfolding codes MAXED, GRAVEL and MLEM have been compared using plastic scintillator simulated data. • Comparing the calculated mean squared error (MSE) performed by the three unfolding methods, we find that MLEM seems to perform better than MAXED and GRAVEL. • Utilizing the Watt spectrum as the input spectrum enhances the performance of the unfolding codes when compared to using the flat spectrum. [ABSTRACT FROM AUTHOR]

In this work, neutron spectra are unfolded using artificial neural networks (ANNs). The neutron response of the NE213 scintillator detector, characterized by the pulse height distribution, is calculated to obtain the necessary data for unfolding the energy spectrum. This is achieved using both analytical response functions and response functions generated by the MCNPX-PHOTRACK code. In this query, the Levenberg-Marquardt method (LMM), which has a high computational speed in the learning method, is used to train the network. The performance of the ANN for unfolding the neutron energy spectrum of the NE213 scintillation detector was evaluated by comparing its results to the established Gravel method. The ANN method consistently produced spectra with a single peak closely matching the incident energy, while the Gravel method showed additional peaks and distortions. Quantitative analysis revealed a lower relative energy peak difference (indicating higher accuracy) for the ANN method compared to Gravel, particularly when noise was introduced into the data. These results suggest that ANNs offer a more robust and accurate approach for neutron spectrum unfolding. • The neutron energy spectrum was unfolded using LMBP algorithm. • A two-layer neural network for energy spectrum unfolding was developed. • In the LMBP method, the time and cost of calculations are reduced considerably. • A comparison of LMBP with GRAVEL shows that both methods are very efficient. [ABSTRACT FROM AUTHOR]

The development of Eu2+-activated oxide materials with high efficiency, fast decay and narrow bandwidth emission in the visible region is still challenging for the field of luminescence and scintillation applications. Generally, Eu2+ in oxide hosts can emit intense and broad 5d-4f emission in the visible region, but efficient emitting with stable bivalence of Eu is rare in inorganic oxide system. In this work, a series of ASL:Eu2+ (Sr 1-x La x Mg x Al 12-x O 19) powder samples with various La, Mg doping ratios were designed and synthesized to modulate the UV or X-ray excited luminescence properties, including redshift, quantum yield, and decaying lifetime. Moreover, an ASL:Eu2+ crystal with the optimal ratio x = 1/3 was grown, its scintillation performance was compared with standard Bi 4 Ge 3 O 12 crystal sample and evaluated in detail. These results indicate that the ASL:Eu2+ crystal is potential scintillator as a kind of X-ray detection and provide a reference for the further development of high-performance Eu-activated oxide scintillation materials. • The La, Mg dopants in SrAl 12 O 19 host promotes the red shift of Eu2+ emission under UV excitation. • The ASL:Eu2+ shows the self-trapped excitons radiation in XEL spectra. • The light yield of the as-grown ASL:Eu2+ crystal was determine to be 111.6 p.e./MeV. [ABSTRACT FROM AUTHOR]

Gd 2 O 2 S:Pr,Ce nanophosphors have been prepared by liquid-phase method using NH 2 SO 3 H as the sulfur source for the first time. The formula of the novel precursor was determined as Gd 2 (OH) x (NH 2 SO 3) 6-x ∙nH 2 O by EDS, TG-DSC and FT-IR spectroscopy, and the precursor exhibited an amorphous structure and lamellar morphology as deduced from XRD and SEM. The optimum pH was 8 and the optimum calcination temperature was 1000 °C for the preparation of Gd 2 O 2 S:Pr,Ce from the precursor. The PL quantum yield and the fluorescence lifetime of Gd 2 O 2 S:Pr,Ce powder was 53.62 % and 2.48 μs respectively, which will allow the preparation of ceramic scintillators with high optical output and energy resolution. Compared to the traditional sulfur sources such as sublimed sulfur, and H 2 SO 4 , NH 2 SO 3 H is harmless and avoids pollution gases during the preparation of Gd 2 O 2 S:Pr,Ce nanophosphors. It also eliminates the need to add additional reagents, simplifying the preparation steps and reducing production costs. • GOS powder was synthesized by using a new sulfur source NH 2 SO 3 H for the first time. • The novel precursor Gd 2 (OH) x (NH 2 SO 3) 6-x ∙nH 2 O was analyzed in detail. • GOS powder was with high PL quantum yield and short fluorescence lifetime. [ABSTRACT FROM AUTHOR]

We developed BaCl 2 :Yb transparent ceramics by the spark plasma sintering method and evaluated their optical and scintillation properties. An emission peak in the photoluminescence and scintillation spectra was observed at 440 nm due to the spin-forbidden 4f135d1–4f14 transition of Yb2+. The afterglow levels of the BaCl 2 :Yb transparent ceramics were lower than those of a commonly used inorganic scintillator CsI:Tl and CdWO 4. The scintillation light yield of the 0.5% doped BaCl 2 :Yb transparent ceramic was 2400 ph/MeV under 137Cs γ-ray irradiation, and the value is low in comparison with those of other Yb-doped halide materials. • BaCl 2 :Yb transparent ceramics were fabricated to evaluate the scintillation properties. • The scintillation peak due to 4f135d1–4f14 transition of Yb2+ was observed at 440 nm. • The afterglow levels were better than those of practical X-ray scintillators such as CsI:Tl. • The 0.5% BaCl 2 :Yb sample showed the highest light yield (2400 ph/MeV) under 137Cs γ-ray irradiation in the samples. [ABSTRACT FROM AUTHOR]

Sm-doped CaCl 2 , SrCl 2 , and BaCl 2 bulk crystals were synthesized using the conventional vertical Bridgman method, and the photoluminescence, radioluminescence, and detector properties were evaluated. The Sm-doped CaCl 2 , SrCl 2 , and BaCl 2 samples show a broad emission band at 750, 690, and 650 nm, respectively, which is attributable to the 5d-4f transitions of Sm2+. The pulse height spectra under 137Cs γ-rays (662 keV) show that the Sm-doped CaCl 2 and SrCl 2 exhibit 9300 and 33000 photons/MeV, respectively. These samples can be used for γ-ray measurements in the red to NIR region. • Sm-doped CaCl 2 , SrCl 2 , and BaCl 2 crystals were synthesized using the conventional vertical Bridgman method. • The photoluminescence, radioluminescence, and detector properties were evaluated. • The samples show a broad emission band at 600–800 nm due to Sm2+. • Sm-doped CaCl 2 , SrCl 2 , and BaCl 2 exhibit light yield of 9300, 33000, and 16000 photons/MeV, respectively. [ABSTRACT FROM AUTHOR]

In order to estimate the stability of the light output of the scintillation detector, the Lu 2 SiO 5 :Ce scintillation crystals, additionally doped with Ca2+ ions at concentrations of 0 ÷ 0.4 at%, were studied. The spectra of optical absorption, gamma-luminescence, thermal luminescence, dose and temperature dependences of luminescence were measured. Gamma-luminescence in the dose range 10 - 5·107 Gy was recorded using 60Co gamma-source at the temperature range of 310–460 K. In contrast to the initial sample (non-doped with Ca), in the sample doped with 0.1 at% of Ca, an increase in the luminescence intensity was observed in the range of 390–425 nm, but further with an increase in the concentration of Ca (0.3–0.4 at%), the intensity of this band decreased to the initial level (undoped). At Ca concentrations of 0.3 and 0.4 at%, the intensity of the Ce1 center band remains practically unchanged up to a dose of 5·107 Gy. LSO crystals doped with Ce 0.1 at% and co-doped with Ca 0.1 at% can be recommended as a scintillation detector up to a gamma-dose of 105 Gy at room temperature. • Ca-codoped Lu 2 SiO 5 :Ce crystals are studied as a material for scintillation detector. • At Ca 0.1 at% an increase in the luminescence at 390–425 nm was observed. • At Ca 0.3 at% the Ce1 center emission doesn't change up to a γ-dose of 5·107 Gy. • Defect complexes completely discolor at room temperature in two days. [ABSTRACT FROM AUTHOR]

Single crystals of Gd 3 (Ga,Al) 5 O 12 :Ce,Mg with different concentration of Mg2+ ions varying from 0 to 0.029 at.% are investigated by the X-ray diffraction, steady-state and time-resolved photoluminescence, and thermally stimulated luminescence (TSL) methods in a wide temperature range (77–510 K). The origin and structure of the luminescence centers are considered. The influence of Mg2+ ions on the structure of the Ce3+-related excited state, the processes taking place in this state, and the TSL characteristics is clarified. At low temperatures, the photoluminescence optical quenching in close {Ce3+ - Mg2+} pairs is found to be responsible for the light yield reduction accompanied with the acceleration of the luminescence decay kinetics. At room temperature, the luminescence quenching can be additionally caused by the thermal ionization of the 5d 1 excited state of Ce3+ ion, whose probability increases with the increasing Ga content. The conclusion is made that in order to create the fast scintillator with the maximum light yield, the concentration of intrinsic crystal lattice defects in Gd 3 (Ga,Al) 5 O 12 :Ce,Mg should be minimized, the optimum composition of the host should be chosen, and the balance between the concentrations of the doped Mg2+ and Ce3+ ions should be optimised. • Photo- and thermoluminescence and XRD of Gd 3 (Ga,Al) 5 O 12 :Ce,Mg crystals are studied. • Influence of Mg2+ ions on the Ce3+-related luminescence and excited states is clarified. • Optical quenching in close {Ce3+ - Mg2+} pairs results in the light yield reduction and accompanied with acceleration of the Ce3+ luminescence decay kinetics. • Ga3+ ions and intrinsic defects strongly influence the luminescence thermal quenching. • Optimum host composition and preferable Ce3+/Mg2+ concentration ratio are considered. [ABSTRACT FROM AUTHOR]

This paper introduces the characteristics of the LYSO-SiPM-based receiver used in X-ray communication (XCOM). The X-ray signal receiving scheme based on a scintillator and photodetector is an important part of the XCOM system. However, the inherent characteristics of the scintillator and photodetector hinder the improvement of the performance of the X-ray signal receiver. Thus, this paper proposes a comprehensive analysis model for modeling the counting statistical characteristics of the LYSO-SiPM-based receiver, and analyzes the effects of the receiver's characteristics on the communication performance of the OOK-modulated XCOM system. Furthermore, the LYSO-SiPM pulse X-ray signal receiver is optimized, and its performance in the XCOM experiment is tested. The experimental results are consistent with the theoretical analysis trend, indicating that the proposed analytical model can be used for XCOM performance analysis and optimization. [ABSTRACT FROM AUTHOR]

Muography using cosmic ray muons is a non-invasive and environmentally friendly imaging technique with comprehensive applicability across various fields such as mineral exploration, archaeology, and engineering, etc. Given characteristics of high penetration and broad energy spectrum of cosmic ray muons, three-dimensional density distribution of objects up to hundreds of meters can be well reconstructed. In mineral exploration and archaeology applications, conventional planar detectors are too large and usually deployed in spacious rooms like tunnels or outdoors, which seriously limits the deeper and broader applications of muography. A type of borehole muon detector is highly desired to address this. In the work, we introduce a novel borehole-type muography detector comprising annular and prismatic plastic scintillators, allowing for its deployment in boreholes. In the paper, the structural design of the detector is described in details and its performance is evaluated numerically and experimentally. Comprehensive investigation on components and on the system as a whole were conducted. According to our commissioning tests, the detector we propose has an omnidirectional field of view without blind spots, with an angular uncertainty of 27.4 mrad and a position uncertainty of 2.29 mm in the azimuthal direction, an angular uncertainty of 20.6 mrad and a position uncertainty of 10.31 mm in the zenithal direction. Detection efficiencies for both annular and prismatic scintillators were measured as 90.3 ± 0.53% and 92.27 ± 0.82%. In addition, an underground location was investigated, survival rate distributions being calculated from above-ground and underground measurements. The results indicate its capability to successfully address muography applications This novel borehole-type detector has the potential to address industry demand for lower-cost, more flexible muography solutions. • Achieves high angular resolution and full 360° omnidirectional detection within a compact borehole-sized format. • Maintains >90% detection efficiency across scintillator sections. • Utilizes a simplified single-ended readout design with fewer electronic channels. • Employs low-cost, easy-to-process plastic scintillators as the primary component. [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]

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]

An energetic proton beam with a high divergence cone angle of ∼10°, generated by the interaction of a 25 fs, 800 nm Ti: Sapphire laser pulse with a thin metal foil target, was transported and focused at a specified distance from the source. A pulsed high-voltage solenoid, which generates a magnetic field of 5.7 T at a current of 8 kA, was developed in-house for this purpose. The profile of the proton beam was monitored online at various positions using a combination of a fast thin plastic scintillator and a CCD camera. The effect of solenoid misalignment on the focused proton beam was also investigated experimentally. In addition, the proton beam was transported out of the vacuum chamber into the ambient air for radiography application. A proton flux of ∼2 × 108 protons (energy >4 MeV) was transported and focused at a distance of 1.27 m from the target with a transmission efficiency of 30 % in a single shot. Detailed simulations incorporating particle tracing and transfer matrix method were performed to highlight the role of beam chromaticity and the impact of spherical harmonics on the focusing characteristics of the solenoid. The simulation results qualitatively reproduce the experimental observations. The solenoid provides energy-selective proton focusing for a broad energy proton beam. The proton beam was used for the radiography of reference meshes and has the potential to be used for radiobiological irradiation studies. [ABSTRACT FROM AUTHOR]

We report on the development of a custom particle detection system that aims to improve the detection capabilities of the ROSPHERE array. The detector is designed specifically for lifetime measurements using the in-beam Fast-timing method for nuclear states in nuclides produced in nuclear transfer reactions. An 80 x 3.6 mm disc of BC400 plastic scintillator was coupled to a sparse SiPM array readout connected to a dedicated Front End Electronics board. The detector was tested versus a conical LaBr 3 (Ce) coupled to a Hamamatsu PMT readout. The timing measurements resulted in a resolution of 896(5) ps. The detector design, characteristics, and performances are presented in this paper along with future improvements. [ABSTRACT FROM AUTHOR]

It is important to differentiate between natural and artificial radioactive materials such as plutonium in nuclear facilities. In this study, a scintillator-based alpha-particle detector was developed using YAP:Ce scintillator and Multi-Anode PhotoMultiplier Tube. The detector was used to measure various naturally occurring radioactive materials (NORM) samples including radon progeny, lead plate, lantern mantle, and radium ceramic ball. The measurement results were compared with Monte Carlo simulation calculations and were found to be in agreement. The energy resolution of the detector is 8.6%FWHM. In the measurement results of radon progeny, peaks of 212Bi (6.1 MeV), 214Po (7.7 MeV), and 212Po (8.8 MeV) can be observed. The lead plate contains 210Po and emits 5.3 MeV alpha particle. The simulation with the same energy was able to reproduce the actual measurement. The results showed the energy and distribution of the alpha particles emitted by the NORM samples. The study successfully demonstrated the capability of the developed alpha-particle detector in identifying NORM. [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]

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]

Particle dark matter could belong to a multiplet that includes an electrically charged state. WIMP dark matter (χ 0) accompanied by a negatively charged excited state (χ −) with a small mass difference (e.g. < 20 MeV) can form a bound-state with a nucleus such as xenon. This bound-state formation is rare and the released energy is O (1 − 10) MeV depending on the nucleus, making large liquid scintillator detectors suitable for detection. We searched for bound-state formation events with xenon in two experimental phases of the KamLAND-Zen experiment, a xenon-doped liquid scintillator detector. No statistically significant events were observed. For a benchmark parameter set of WIMP mass m χ 0 = 1 TeV and mass difference Δ m = 17 MeV, we set the most stringent upper limits on the recombination cross section times velocity 〈 σ v 〉 and the decay-width of χ − to 9.2 × 10 − 30 c m 3 / s and 8.7 × 10 − 14 GeV, respectively at 90% confidence level. [ABSTRACT FROM AUTHOR]

CYGNO is an international collaboration with the aim of operating a ▪ optical time projection chamber (TPC) for directional Dark Matter (DM) searches and solar neutrino spectroscopy, to be deployed at the Laboratori Nazionali del Gran Sasso (LNGS). A ▪/▪ (60/40) mixture is used, along with a triple Gas Electron Multiplier (GEM) cascade to amplify the ionisation signal. The scintillation produced in the electron avalanches is read out using a scientific complementary metal–oxide–semiconductor (sCMOS) camera. This solution has proven to provide very high sensitivity to interactions in the few ▪ energy range. The inclusion of a hydrogen-based gas will offer an even lighter target, resulting in a more efficient energy transfer in a DM particle collision, and consequently, a lower detection threshold. Additionally, longer track lengths of light nuclear recoils are easier to detect with a clearer direction. However, the addition of such gas will contribute to quenching the scintillation, jeopardizing the TPC performance. In this work, we demonstrate the feasibility of adding 1% to 5% isobutane to the ▪/▪ (60/40) mixture by measuring the respective absolute scintillation yield output. The overall scintillation produced in the charge avalanches is not drastically suppressed by quenching due to the isobutane addition. The presence of Penning transfer from excited He atoms to isobutane molecules increases the number of electrons in the avalanches, partially compensating for the loss of scintillation due to quenching. For the highest applied GEM voltage, the total number of photons produced in the avalanche per ▪ deposited in the absorption region presents a decrease of only a factor of about three, from 2.30 (20) × 10 4 to 8.2 (4) × 10 3 ▪, as the isobutane content increases from 0 to 5%. The quantification of the visible component of the scintillation shows that isobutane quenches both visible and ultraviolet (UV) photons emitted by ▪/▪. [ABSTRACT FROM AUTHOR]

Cerium-doped yttrium aluminum gallium garnet (YAGG:Ce3+) nanophosphors were synthesized using the sol-gel method. Mixed garnet of Y 2.97 Al 5-x Ga x O 12 :Ce 0.03 was prepared with varying gallium content: x = 0, 1, 2 and 3 Ga. The effect of gallium substitutions on the structural, photo and thermoluminescence properties of the prepared nanophosphors were studied by X-ray diffraction (XRD), photoluminescence (PL) and thermoluminescence (TL) techniques. XRD results indicated that the single and pure cubic crystal phase was formed for all nanophosphor samples regardless of the Ga content. The PL spectra of all the samples exhibited a green-yellow emission band centered at 522 nm attributed to the 5d → 4f transitions of Ce3+ ions. The TL glow curve spectra recorded after β-particle irradiation showed a strong dependence in terms of position, shape and intensity, of all temperature peaks with the Ga content. The highest TL sensitivity was observed for the sample prepared with x = 2 Ga, with main peak arising at low temperature (85 °C). The sample prepared at x = 1 Ga exhibited also high TL sensitivity with a simple glow curve spectrum showing a main peak at high temperature (∼158 °C). Thus, the linear dose response of this sample has been investigated in the wide dose range from 0.125 to 100 Gy in order to evaluate the potentiality of this material for radiation dosimetry applications. • Y 3 Al 5-x Ga x O 12 :Ce3+ (x = 0, 1, 2 and 3) nanogarnets were successfully synthesized using sol–gel method. • Structural, photo and thermoluminescence properties of prepared samples exhibited a strong dependence on Ga content. • Pure garnet phase was formed for all prepared samples. • TL glow curve of Y 2.97 Al 4 Ga 1 O 12 :Ce 0.03 exhibited high intensity and simple TL curve suitable for dosimetry. • Y 2.97 Al 4 Ga 1 O 12 :Ce 0.03 demonstrated a good linear behavior within the range 0.125–100 Gy. [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]

Lanthanum barium borate glasses doped with Eu3+ ions were synthesized using a melt quenching method, with a nominal chemical composition of {10La 2 O 3 –20BaO-(70-x)B 2 O 3 -xEu 2 O 3 ; 0.0 ≤ x ≥ 7.0} mol%. These glass samples were characterized, including assessments of their physical, structural, optical, and luminescent properties. The emission spectra, both of photoluminescence and radioluminescence studies were presented and found featuring five distinct peaks at 577 nm (5D 0 →7F 0), 590 nm (5D 0 →7F 1), 613 nm (5D 0 →7F 2), 652 nm (5D 0 →7F 3), and 701 nm (5D 0 →7F 4). Interestingly, concentration quenching effects were observed at Eu3+ concentrations of 3.0 mol% and 5.0 mol% for photoluminescence and radioluminescence respectively. The decay time of LaBaBEu3.0 show 1.617 ms and the quantum yield reaching value of 14.16%. The CIE 1931 chromaticity coordinates of these glasses show reddish-orange color. This reddish-orange color was particularly observed when the samples were excited under a UV lamp. • La 2 O 3 –BaO–B 2 O 3 –Eu 2 O 3 glasses were prepared. • Highest quantum yield is14.16% at 3.0 % mol of Eu 2 O 3. • CIE 1931 shows reddish-orange color emission. • Best integral scintillation efficiency is 14.85% of BGO. • Ω2 highest value at 3.0 % mol of Eu 2 O 3, correspond to asymmetry and emission intensity. [ABSTRACT FROM AUTHOR]

Strontium phosphate (SrO–P 2 O 5 –Al 2 O 3 –Gd 2 O 3) glasses with 0.05, 0.1, 0.5, and 1 mol % CeO 2 were prepared by the conventional melt quenching technique. These glasses' luminescence, scintillation, and physical properties were measured and discussed in detail. The density, refractive index, and oxygen packing density of the studied glasses were increased with an increase in CeO 2 concentration. At lower concentrations of CeO 2 , the characteristic 310 nm emission from Gd3+ and broadband emission from Ce3+ ions were obtained under X-ray excitations. The intensity of both Gd3+ and Ce3+ emission bands under 270 nm Gd3+ excitations reduced with further increase in CeO 2 , showing the delayed energy transfer from Gd3+ to Ce3+ ions. The integrated X-ray-induced luminescence intensity of 0.5% CeO 2 glass was found to be 21% that of reference BGO crystal. For the lower concentration of CeO 2 , a slow decay time along with the fast Ce3+ decay was observed and disappears for higher CeO 2 concentrations. The fast luminescence decay in the range of 22 ns–30 ns was observed for all the PSAG:Ce glasses, which was attributed to the lifetime of the 4f-5d transition of the Ce3+ ions. The faster decay time and reasonable scintillation light suggest the application of these glasses for radiation detector applications. • Strontium phosphate glasses with various concentrations of CeO 2 are fabricated. • The density, refractive index, and OPD increased with CeO 2 concentrations. • Efficient energy transfer from Gd3+ to Ce3+ was confirmed from luminescence. • X-ray-induced scintillation light was found to be 21% that of BGO crystal. [ABSTRACT FROM AUTHOR]

A simple method of in-situ growth using anodized aluminum oxide templates is used to prepare a high-resolution pixelated scintillator array Cs 5 Cu 3 Cl 6 I 2 with enhanced light direction limitation for X-ray imaging, The Cs 5 Cu 3 Cl 6 I 2 @AAO film performs excellent stability under long-term X-ray irradiation, making it a reliable option for cost-effective pixelated indirect X-ray imaging. [Display omitted] • A perovskite array scintillation film Cs 5 Cu 3 Cl 6 I 2 @AAO via an in-situ growth strategy was fabricated. • A spatial resolution of approximately 20 lp mm−1 and a detection limit of 0.152 μGy·s−1 were achieved. • Excellent stability under long-term X-ray irradiation of Cs 5 Cu 3 Cl 6 I 2 @AAO was studied. Lead-free halide perovskites have shown promising application for indirect X-ray detection as fascinating scintillator. The fabrication of pixelated scintillator films leveraging directional confinement allows high-resolution imaging, yet process complexity and the potential crystal structure damage pose challenges that compromises the corresponding scintillator performance. In this work, a facile in-situ strategy for growing scintillation perovskite of Cs 5 Cu 3 Cl 6 I 2 within anodic aluminum oxide (AAO) membrane is developed as scintillator Cs 5 Cu 3 Cl 6 I 2 @AAO film. The as-fabricated pixelated scintillator array with an enhanced light directional confinement for high-resolution X-ray imaging is demonstrated. The corresponding film achieves a spatial resolution of approximately 20 lp mm−1 and a detection limit of 0.152 Gy·s−1. Moreover, the Cs 5 Cu 3 Cl 6 I 2 @AAO film performs excellent stability under long-term X-ray irradiation, making it a reliable option for cost-effective pixelated indirect X-ray imaging. [ABSTRACT FROM AUTHOR]