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The ProtoDUNE-SP detector is a single-phase liquid argon time projection chamber (LArTPC) that was constructed and operated in the CERN North Area at the end of the H4 beamline. This detector is a prototype for the first far detector module of the Deep Underground Neutrino Experiment (DUNE), which will be constructed at the Sandford Underground Research Facility (SURF) in Lead, South Dakota, U.S.A. The ProtoDUNE-SP detector incorporates full-size components as designed for DUNE and has an active volume of 7 × 6 × 7.2 m3. The H4 beam delivers incident particles with well-measured momenta and high-purity particle identification. ProtoDUNE-SP's successful operation between 2018 and 2020 demonstrates the effectiveness of the single-phase far detector design. This paper describes the design, construction, assembly and operation of the detector components.

Cone-beam computed tomography (CBCT) has emerged in recent years as an adequate alternative to mammography and tomosynthesis due to the several advantages over traditional mammography, including its ability to provide 3D images, its reduced radiation dose, and its ability to image dense breasts more effectively and conduct more effective breast compressions, etc. Furthermore, CBCT is capable of providing images with high sensitivity and specificity, allowing a more accurate evaluation, even of dense breasts, where mammography and tomosynthesis may lead to a false diagnosis. Clinical and experimental CBCT systems rely on cesium iodine (CsI:Tl) scintillators for X-ray energy conversion. This study comprises an investigation among different novel CBCT detector technologies, consisting either of scintillators (BGO, LSO:Ce, LYSO:Ce, LuAG:Ce, CaF2:Eu, LaBr3:Ce) or semiconductors (Silicon, CZT) in order to define the optimum detector design for a future experimental setup, dedicated to breast imaging. For this purpose, a micro-CBCT system was adapted, using GATE v9.2.1, consisting of the aforementioned various detection schemes. Two phantom configurations were selected: (a) an aluminum capillary positioned at the center of the field of view in order to calculate the system’s spatial resolution and (b) a breast phantom consisting of spheres of different materials, such that their characteristics are close to the breast composition. Breast phantom contrast-to-noise ratios (CNRs) were extracted from the phantom’s tomographic images. The images were reconstructed with filtered back projection (FBP) and ordered subsets expectation-maximization (OSEM) algorithms. The semiconductors acted satisfactorily in low-density matter, while LYSO:Ce, LaBr3:Ce, and LuAG:Ce presented adequate CNRs for all the different spheres’ densities. The energy converters that are presented in this study were evaluated for their performance against the standard CsI:Tl crystal.

X‐ray induced photodynamic therapy (X‐PDT) circumvents the poor penetration depth of conventional PDT with minimal radio‐resistance generation. However, conventional X‐PDT typically requires inorganic scintillators as energy transducers to excite neighboring photosensitizers (PSs) to generate reactive oxygen species (ROS). Herein, a pure organic aggregation‐induced emission (AIE) nanoscintillator (TBDCR NPs) that can massively generate both type I and type II ROS under direct X‐ray irradiation is reported for hypoxia‐tolerant X‐PDT. Heteroatoms are introduced to enhance X‐ray harvesting and ROS generation ability, and AIE‐active TBDCR exhibits aggregation‐enhanced ROS especially less oxygen‐dependent hydroxyl radical (HO•−, type I) generation ability. TBDCR NPs with a distinctive PEG crystalline shell to provide a rigid intraparticle microenvironment show further enhanced ROS generation. Intriguingly, TBDCR NPs show bright near‐infrared fluorescence and massive singlet oxygen and HO•− generation under direct X‐ray irradiation, which demonstrate excellent antitumor X‐PDT performance both in vitro and in vivo. To the best of knowledge, this is the first pure organic PS capable of generating both 1O2 and radicals (HO•−) in response to direct X‐ray irradiation, which shall provide new insights for designing organic scintillators with excellent X‐ray harvesting and predominant free radical generation for efficient X‐PDT. [ABSTRACT FROM AUTHOR]

The luminescence and scintillation properties of Ce3+ doped alkali phosphate glasses 56P 2 O 5 :8Gd 2 O 3 :5Al 2 O 3 :1CeBr 3 :30XCl (PGAC:X, X = Li/Na/K/Rb/Cs) were studied for their potential applications in gamma and alpha detection. In the Fourier Transform Infrared Spectroscopy (FTIR), X-ray Luminescence (XRL), Photoluminescence (PL), and transmittance spectra, the red shift was found and explained by the concept of optical basicity. Broad Ce3+ emission and energy transfer from Gd3+ to Ce3+ were observed in XRL and PL measurements. Scintillation performance was studied by irradiating the samples under 137Cs gamma and 241Am alpha sources. The fast, intermediate, and slow decay components under gamma and alpha excitation were found around 30, 200 and 3000 ns, respectively. The decay time increased slightly from PGAC:Li to PGAC:Cs, indicating the less effective transition from Gd3+ to Ce3+. The alpha decay time was longer than the gamma decay time, revealing the Pulse Shape Discrimination (PSD) capability of the glasses for particle identification. The XRL intensity reduced significantly from PGAC:Li to PGAC:Cs samples did not reflect the scintillation tendency. By successfully detecting gamma and alpha scintillation signals, the scintillation performance of all samples was found to be similar. In general, all samples can be used for gamma and alpha detection. Using Rb+ or Cs+ ions is favorable in terms of high density and light yield, while Li+ ions enhance the transmittance and homogeneity. Furthermore, a correlation between P–O–H groups within the glass matrix and scintillation performance was also observed. [ABSTRACT FROM AUTHOR]

In this paper, we report the first Bi4Ge3O12-based thin-layer alpha radiation detector. The scintillator was immobilized on a fused silica substrate via pulsed laser irradiation of BGO powder consisting of submicron particles. Laser treatment conditions were shown to influence the morphology and kinetic characteristics of the scintillator. The material we prepared ensures a higher stability of detectors to moisture and air in comparison with its commercially available analogs, while offering a comparable or even higher detection efficiency, and can be used in environmental monitoring, including volumetric alpha activity measurements. [ABSTRACT FROM AUTHOR]

Catalysts derived from Ni/Al/Mg/Ce hydrotalcite were prepared via a co-precipitation method, varying the Ce/Al atomic ratio. All of the catalytic systems thus prepared were tested for CO2 methanation under dark and photocatalytic conditions (visible and ultraviolet) under continuous flow with the light intensity set to 2.4 W cm−2. The substitution of Al by Ce formed a solid solution, generating oxygen vacancies and Ce3+/Ce4+ ions that helped shift the dissociation of CO2 towards the production of CH4, thus enhancing the activity of methanation, especially at lower temperatures (<523 K) and with visible light at temperatures where other catalysts were inactive. Additionally, for comparison purposes, Ni/Al2O3-based catalysts prepared via wetness impregnation were synthesized with different Ni loadings. Analytical techniques were used for the characterization of the systems. The best results in terms of activity were as follows: Hydrotalcite with Ce promoter > Hydrotalcite without Ce promoter > 25Ni/Al2O3 > 13Ni/Al2O3. Hydrotalcite, with a Ce/Al atomic ratio of 0.22 and a Ni content of 23 wt%, produced 7.74 mmol CH4 min−1·gcat at 473 K under visible light. Moreover, this catalyst exhibited stable photocatalytic activity during a 24 h reaction time with a CO2 conversion rate of 65% and CH4 selectivity of >98% at 523 K. This photocatalytic Sabatier enhancement achieved activity at lower temperatures than those reported in previous publications. [ABSTRACT FROM AUTHOR]

This paper is devoted to the current status of the novel fully active 3D (three-dimensional) fine-grained scintillator detector SuperFGD as a main part of the near off-axis detector upgrade program for the T2K experiment. The following important components related to the SuperFGD such as SuperFGD electronics and mechanics, wavelength shifting (WLS) fibers, and light emitting diode (LED) calibration system are also discussed here as well as the detector's near future. [ABSTRACT FROM AUTHOR]

Single-phase samples of the Ba1−xCexF2+x solid solution (x = 0.3–0.4) were synthesized by directional crystallization in the form of single crystals and by co-precipitation from aqueous nitrate solutions using potassium fluoride as a fluorinating agent in the form of nanopowders. The cathodoluminescence of the pressed powder samples was studied in comparison with the BaF2: Ce single crystals in 250–460 nm (2.7–5 eV) spectral range upon excitation by an electron accelerator. The cathodoluminescence spectra of the samples revealed a wide band in the range of 3.0–4.0 eV, which consists of two typical components of Ce3+ with decay time 23 ns in the case of single crystals and three decay times 27 ns, 140–170 ns, and ~600 ns in the case of pressed powders. The decay time of the short-wavelength component (27 ns) in the case of pressed powders is close to the lifetime of the excited state of the Ce3+ ion. The developed X-ray phosphors can be applied for embedding in diamonds for diamond–nanoparticle composite preparation. [ABSTRACT FROM AUTHOR]

The production of scintillating ceramics can require the utilization of the phosphorus compounds at certain stages of 3D-printing, such as vat polymerization, applied for the formation of green bodies before sintering. The effect of phosphorus additive on the microstructure, optical, and scintillation parameters of Gd1.494Y1.494 Ce0.012Al2Ga3O12 (GYAGG:Ce) ceramics obtained by pressureless sintering at 1650 °C in an oxygen atmosphere was investigated for the first time. Phosphorus was introduced in the form of NH4H2PO4 into the initial hydroxycarbonate precipitate in a wide concentration range (from 0 to 0.6 wt.%). With increasing of phosphorus concentration, the density and the optical transmittance of garnet ceramics show a decrease, which is caused by an increase in the number of pores and inclusions. The light yield of fast scintillation, which is caused by Ce3+ ions, was found to be affected by the phosphorus additive as well. Moreover, an increase in phosphorescence intensity was recognized. [ABSTRACT FROM AUTHOR]

Scintillation-based X-ray imaging can provide convenient visual observation of absorption contrast by standard digital cameras, which is critical in a variety of science and engineering disciplines. More efficient scintillators and electronic postprocessing derived from neural networks are usually used to improve the quality of obtained images from the perspective of optical imaging and machine vision, respectively. Here, we propose to overcome the intrinsic separation of optical transmission process and electronic calculation process, integrating the imaging and postprocessing into one fused optical–electronic convolutional autoencoder network by affixing a designable optical convolutional metasurface to the scintillator. In this way, the convolutional autoencoder was directly connected to down-conversion process, and the optical information loss and training cost can be decreased simultaneously. We demonstrate that feature-specific enhancement of incoherent images is realized, which can apply to multi-class samples without additional data precollection. Hard X-ray experimental validations reveal the enhancement of textural features and regional features achieved by adjusting the optical metasurface, indicating a signal-to-noise ratio improvement of up to 11.2 dB. We anticipate that our framework will advance the fundamental understanding of X-ray imaging and prove to be useful for number recognition and bioimaging applications. [ABSTRACT FROM AUTHOR]

Organic–inorganic halide perovskite single crystals (SCs) are promising materials for detecting ionizing radiation owing to their outstanding photoelectric conversion capability and inexpensive solution processability. However, the accuracy and stability of the detectors have been limited due to the charge traps and defects in SCs, especially when operated under high‐precision photon‐counting mode for energy spectrum acquisition. Here, we proposed a trap freezing deactivation route, which obviously suppressed dark current and noise by up to 97% and 92%, respectively. Furthermore, the bulk ion migration effect was essential for the ability to instantly self‐heal defects induced by radiation damage at temperatures down to −30°C. Consequently, the detector exhibits a record high energy resolution of 7.5% at 59.5 keV for 241Am γ‐ray source, which is the best solution‐processed semiconductor radiation detectors at the same energy range. In addition, the detector maintains over 90% of its initial performance after 9 months of storage when tested in the air. Our results will represent a revision of the paradigm that high‐spectral‐resolution and robust radiation detectors can only be realized with high temperature grown inorganic semiconductor single crystals. [ABSTRACT FROM AUTHOR]

CsI(Tl) scintillation screens have been widely applied in X-ray nondestructive testing (NDT) because of their low cost, high scintillation efficiency, and fluorescence guide columnar microstructures. The effect of humidity exposure on the microstructure and photoluminescence properties of polycrystalline CsI(Tl) screens was investigated in this work. The results indicate that the grain diameter of the columnar microstructure increased with increased exposure time in a humid environment. The degree of anisotropy of polycrystalline screens changed from (211) and (310) to (110) orientation with exposure time. FT-IR Spectra of the exposed screens peaked at 3734 cm−1, 3710 cm−1, 3676 cm−1, 3647 cm−1, 3627 cm−1, 3598 c−1, and 3566 cm−1 due to the symmetrical and asymmetrical stretching vibrations of water molecules. In addition, the photoluminescence properties of exposed screens decreased with increased humidity exposure time due to the deliquescence caused by water molecules. After hours of humidity exposure, the photoluminescence and imaging properties of the screens decrease obviously and tend to reduce slowly. The moisture absorption and deliquescence would directly affect the service reliability and the storage lifetime of polycrystalline CsI(Tl) screens. [ABSTRACT FROM AUTHOR]

Organic–inorganic composite scintillators, demonstrating advantages of easy large-area preparation and a high detection efficiency, have shown enormous potential application prospects in radiation detection and imaging. In this study, bulk polystyrene (PS) composite scintillators were successfully prepared by embedding inorganic BaF2 particles with a loading amount of up to 80 wt% during the polymerization process of the plastic scintillator. The inorganic BaF2 particles were uniformly dispersed in the organic matrix. With the increase of the loading amounts of BaF2 particles, the X-ray-excited luminescence intensity of the PS-BaF2 composite scintillators was about eight times higher than that of the commercial pure plastic scintillator. The scintillation counts under the gamma ray (59.5 KeV) irradiation also showed that the detection efficiency was obviously enhanced by BaF2 particle loading. More importantly, their scintillation pulse retains the decay kinetics of the organic matrix without loading the slow-decay component of BaF2. This work provides a promising solution for the application of the PS-BaF2 composite scintillator in high-efficiency radiation detection and large-area imaging. [ABSTRACT FROM AUTHOR]

This study estimates the scale sizes of the plasma density irregularities and the longitudinal width associated with equatorial plasma bubbles (EPBs) in equatorial and low-latitude regions. By analyzing amplitude scintillation S4 indices and total electron content (TEC) measured from low earth orbit (LEO) satellite's beacon signals with 400 MHz and Global Navigation Satellite System (GNSS) L1/E1 signals with 1575.42 MHz, recorded by receivers at the KMITL station in Bangkok, Thailand (geographic; 13.73° N, 100.77°E, magnetic: 7.26°N), we investigate the characteristics of these irregularities. We collected data of 154 LEO satellite pass events during nighttime on 21 disturbed days in four equinoctial months in 2021. Based on the presence or absence of the scintillation effects on GNSS and LEO beacon signals, the events are categorized into four classes to estimate the scale size of the plasma density irregularities. The analysis suggests that events with both GNSS and LEO scintillations, as well as events with GNSS scintillation alone, occur predominantly before midnight assuming the presence of the small-scale size of the irregularities within EPB. However, events with only LEO scintillation occur throughout the whole night and some events are observed before the events with both GNSS and LEO scintillations. Post-sunset LEO scintillation alone may be attributed to the onset of EPBs developing at low altitude, while post-midnight LEO scintillation events near the magnetic equator, observed during periods of low GNSS Rate of TEC Index (ROTI) values, are associated with bottom-side ionospheric irregularities but are not linked with EPB. The findings are consistent with previous researches on the generation and decay of electron density irregularities within plasma bubbles. However, this study provides new insights by using specific data sets and analysis techniques, offering a more comprehensive understanding of the association of LEO scintillations with bottom-side ionospheric irregularities near the magnetic equator, not observed in the ROTI map. [ABSTRACT FROM AUTHOR]

This study investigated both the disturbance electric fields processes including the Interplanetary Electric Field (IEFy) to low-latitude, known as prompt penetration electric field (PPEF) and the disturbance dynamo electric field (DDEF), and their effects on ionospheric TEC and scintillations over south China during four storms of 17 March 2015, 15 July 2012, 7 October 2015 and 20 December 2015. GPS ionospheric and magnetometer data were derived from receiver stations at Guangzhou and Shenzhen, and at Guangdong Zhaoqin (GZH) and equatorial station Dalat, respectively. Results presented that cases of the eastward PPEF on dayside with durations of 3 and 8 h were identified during storm main phases of 17 March 2015 and of 20 December 2015 respectively. DDEFs were found to dominate on nightside during the three main storm phases other than storm of 15 July 2012, and on dayside during the recovery storm phase of 21 December 2015. The responses of positive TEC deviation to the eastward PPEF on dayside were identified during the storm main phase of 20 December 2015 rather than during the storm of 17 March 2015, which showed longitudinal, latitudinal and seasonal dependences as compared to the previous studies. During the storm of 15 July 2012, positive TEC deviations with no response to the eastward PPEF on dayside were identified. Negative TEC deviation responses to the DDEF on dayside were seen during all four storm recovery phases. GPS ionospheric scintillations (S 4 ≥ 0.4) dominated in the equinox months before the occurrences of four storms, but were inhibited during the storm of 17 March 2015 over south China, which was attributed to the inhibitions of irregularities caused scintillations. [ABSTRACT FROM AUTHOR]

The technological aspects of the light inorganic crystalline compounds suitable to create scintillation materials to detect charged particles and neutrons in a wide energy range have been examined. Among them, Li2CaSiO4:Eu was found to be a prospective candidate to control the valent state of the Rare Earth (RE) and to provide a high intensity of luminescence. It was demonstrated that the material has room for future improvement; however, this requires precise engineering of its composition—an experimental search of compositions or additives that will provide the maximum Eu2+/Eu3+ ratio to achieve a high scintillation light yield. The benefits of light inorganic materials are disclosed through the modeling of the linear density of nonequilibrium carriers along secondary particle tracks created in scintillators utilized for neutron detection. It is shown that oxide matrices have a larger linear density in comparison with halide crystalline compounds under alpha-particles and tritons, whereas light oxides can provide smaller numbers under protons. [ABSTRACT FROM AUTHOR]

The magnetic properties of magnetic nanocomposites consisting of hard and soft magnetic phases are dependent not only on the intrinsic properties but also on the grain structure and volume ratio of the two phases. In this study, we performed a systematic micromagnetic simulation on the magnetic properties of Ce2Fe14B/α-Fe and Nd2Fe14B/α-Fe nanocomposites. The volume fractions of the hard magnetic Nd2Fe14B or Ce2Fe14B phase were varied from 80% to 40%, and the grain sizes of the hard magnetic phase and the soft magnetic α-Fe phase were changed independently from 10 nm to 40 nm. The results show that when the grain size of both hard and soft phases is 10 nm and the volume fraction of the hard phase is 70%, the highest maximum magnetic energy product can be obtained in both Ce2Fe14B/α-Fe and Nd2Fe14B/α-Fe nanocomposites. The hard magnetic properties of Ce2Fe14B/α-Fe nanocomposite decrease significantly when the volume fraction of the α-Fe phase exceeds 30%. However, for the Nd2Fe14B/α-Fe system, this situation only occurs when the α-Fe volume fraction exceeds 40%. The reason for this is not only because of the low anisotropic field and the smaller exchange coupling length between the soft and hard magnetic phases, but also because of the lower saturation magnetization of the hard phase. The grain size has greater effects on the magnetic properties compared to the volume fraction of the hard magnetic phase. The main reason is that as the grain size increases, the remanence of the nanocomposite decreases sharply, which also leads to a rapid decrease in the maximum magnetic energy product. The simulation results on the effects of phase ratio and grain size have been verified by experiments on melt-spun Ce2Fe14B/α-Fe alloys with various compositions prepared by melt-spinning followed by annealing for various lengths of time. Due to the influence of demagnetization energy, the hard magnetic phase with high saturation magnetization is preferred for the preparation of high-performance nanocomposite magnets. [ABSTRACT FROM AUTHOR]

Plasma irregularity in the equatorial and low-latitude ionosphere, which leads to ionospheric scintillation, can threaten the operation of radio-based communication and navigation systems. A method for forecasting scintillation activity is still pending. In this study, we examined the performance of ionospheric parameters, including the critical frequency (foF2), peak height of the F2-layer (hmF2), scale height (Hm) and virtual height (h'F), around local sunset from ground-based ionosonde observations, and also the characteristics of Equatorial Ionization Anomaly (EIA) derived from Gravity Recovery and Climate Experiment (GRACE) observations in equinoctial months (March–April and September–October) during high solar activities (2012–2013) at a low-latitude station at Sanya (18.3° N, 109.6° E; dip lat.: 12.8° N), China. Furthermore, the simplified linear growth rate of Rayleigh–Taylor (R–T) instability inferred from ionosonde measurements and EIA strength derived from GRACE observations were used to estimate the day-to-day occurrence of post-sunset scintillation. The results indicate that it is not adequate to determine whether scintillation in a low-latitude region would occur or not based on one ionospheric parameter around sunset. The simplified growth rate of R–T instability can be a good indicator for the day-to-day occurrence of scintillation, especially in combination with variations in EIA strength. An index including the growth rate and EIA variations for the prediction of the post-sunset occurrence of irregularity and scintillation is proposed; the overall prediction accuracy could be about 90%. Our results may provide useful information for the development of a forecasting model of the day-to-day variability of irregularities and scintillation in equatorial and low-latitude regions. [ABSTRACT FROM AUTHOR]

The application of a pulsed laser ablation technique for the generation of cerium-doped garnet nanoparticles in liquids is investigated. The morphological and optical properties of the obtained nanoparticles are demonstrated. Features introduced by the single crystals of Gd3Al2.4Ga2.6O12:Ce3+, Lu3Al5O12:Ce3+, and Y3Al1.25Ga3.75O12:Ce3+ from which the nanoparticles are generated, as well as the parameters of a liquid media on the garnet nanoparticle generation are experimentally studied using TEM and UV-Vis spectroscopy methods. It is shown how the size, shape, and internal structure of the nanoparticles are related to the external laser ablation conditions, as well as to the laser melting processes of NPs in the colloidal solutions. This work provides important information about the generated nanoparticles, which can be used as building blocks for specially designed structures with predetermined optical properties. [ABSTRACT FROM AUTHOR]

The Modulation Transfer Function (MTF) characteristics of radiochromic film (RCF) dosimetry with optical systems were evaluated with an RCF, HD-V2, which is transferred with the line patterns of the resolution test chart. In the evaluation using a GT-X980 flatbed scanner, a high contrast spatial resolution with an MTF of ≥0.8 is limited to about 83.3 μm due to artifacts such as scattering of the HD-V2 transmitted light. To achieve high contrast at higher spatial frequencies, a test bench microdensitometer (TBMD) was developed, and its optical performance, dose equivalent response, and spatial resolution characteristics with MTF were evaluated. The TBMD had a minimum readout focal diameter of 13 μm, and its high contrast spatial resolution with an MTF of ≥0.8 is about 11.9 μm. The result that the optical density error increases with decreasing focal diameter in the TBMD supports our hypothesis that these errors are based on the non-uniformity of the shading and surface roughness of the HD-V2 active layer monomers. [ABSTRACT FROM AUTHOR]

[Display omitted] • A high-efficiency and functional NiO/CeO 2 heterostructure nanocatalyst exhibits outstanding HER performance in 1 M KOH with a low overpotential of 99 mV at the current density of 10 mA•cm−2 and a modest Tafel slope of 78.4 mV dec−1. • The atomic-scale analysis of the interfacial structure and the locale electronic states have been provided by the combination of advanced electron microscopic characterization and first principle calculation. • It has been found that the charge transfer occurs from Ni to Ce at the interfacial region, resulting in the valence state variation and increased formation of V O and Ce3+ cations, which would optimize the ΔG H* and facilitate the hydrogen evolution process. • The improved HER performance could be attributed to synergistic coupling interactions and electron redistribution at the interface of NiO and CeO 2. To understand the underlying mechanism of the interfacial charge transfer and local chemical state variation in the nonprecious-based hydrogen evolution reaction (HER) electrocatalysts, a model system of the NiO/CeO 2 heterostructure was chosen for investigation using a combination of the advanced electron microscopic characterization and first-principles calculations. The results directly proved that interfacial charge transfer occurs from Ni to Ce, leading to reduction in the valence state of Ce and increased formation of V O. This would optimize ΔG H* and facilitate the hydrogen evolution process, resulting in outstanding HER performance in 1 M KOH with a low overpotential of 99 mV at the current density of 10 mA•cm−2 and a modest Tafel slope of 78.4 mV•dec−1 for the NiO/CeO 2 heterostructure sample. Therefore, the improved HER performance could be attributed to the synergistic coupling interactions and electron redistribution at the interface of NiO and CeO 2. These results concretely demonstrate the direct determination of the interfacial structure of the heterostructure and provide atomistic insights to unravel the underlying mechanism of interfacial charge transfer induced HER performance improvement. [ABSTRACT FROM AUTHOR]

The growth of the CsI(Tl) scintillators deposited on glass substrates with proper wavelength matching the mainstream semiconductor circuits is crucial for X-ray imaging industry. But the coupling loss between the scintillators and silicon based photo sensors has limited the performance. So fabricating CsI(Tl) films on monocrystalline silicon is greatly important for next-generation high performance X-ray image devices. However, the lattice and thermal mismatch between CsI(Tl) and Si always deteriorates the morphology and structure, and thus degrades the property of the CsI(Tl) scintillation converters. Here, by utilizing crystalline graphene(Gr) as a buffer layer, the van der Waals epitaxial growth of CsI(Tl) film on Si(111) substrate is reported and its advanced applications are demonstrated. The introduced graphene buffer layer extremely frees the stress between CsI(Tl) and Si substrate. Therefore, the CsI(Tl) films show perfect micro-columnar and crystalline structures, and then, exhibit much higher light output and signal to noise ratio, and better modulation transfer functions and a bar pattern X-ray image compared to that on bare Si(111) substrate. This facile method not only lays the foundation for the epitaxy of the alkali halide crystals, including CsI(Tl), onto Si-based detectors and its applications in radiation detection, but also may broaden a new perspective of deposition of CsI(Tl) scintillators into flexible substrates. [ABSTRACT FROM AUTHOR]

In recent years, researchers have been attracted to the tuning of the solar spectrum through a coverglass as a means to enhance the efficiency of a photovoltaic cell by improving the energy transfer mechanism. In this study, energy transfer mechanism was investigated between Gd 3 + and Ce 3 + ions in a bismuth borate glass. Cerium ions (0.1–2.5 mol%) were doped into a bismuth borate glass using a versatile melt-quenching technique in an ambient atmosphere under various experimental conditions. The luminescence and optical properties were examined in relation to the concentration of cerium. The structural changes in the glass matrix that occurred as a result of variation in the concentration were investigated using Fourier transform infrared spectroscopy. To ensure the incident light passage through the glass is not compromised due to self-absorption, optical absorption measurements were carried out to investigate the presence of resonant plasmonic absorption of nanoclusters. The energy bandgap of Ce 3 + -doped glass decreased from 2.772 to 2.671 eV due to dopant concentration-induced structural change in the glass matrix. The photoluminescence properties of the present samples confirmed their suitability for luminescent down converter applications. At UV excitation wavelength of 325 nm, the Ce 3 + -doped samples down-shifted the solar spectrum and gave the most prominent emission band at 448 nm due to the 5d-4f transition of Ce 3 +. The optimum concentration was observed as 0.3 mol%, further increase in the dopant concentration led to a decrease in the emission intensity may be due to the conversion of Ce 4 + into Ce 3 + ions [47,48]. In the energy transfer, Gd 3 + transfers energy non-radiatively to Ce 3 + due to the equivalent energy level 6 P 7 / 2 of Gd 3 + and 5d energy level of Ce 3 +. • Investigated energy transfer between Gd 3 + and Ce 3 + ions in bismuth borate glass • Cerium ions (0.1-2.5 mol%) doped using versatile melt-quenching technique • Ce 3 + -dopant concentration reduced energy bandgap to 2.671 eV • Ce 3 + -doped samples down-shifted solar spectrum, emitted at 448 nm • Optimum dopant concentration observed at 0.3 mol%, higher led to quenching [ABSTRACT FROM AUTHOR]

Gas sensors are useful for monitoring of greenhouse gases. As the move toward complementary metal‐oxide‐semiconductor (CMOS) compatible pyroelectric room temperature detectors is gaining traction due to its scalability to 8‐in./12‐in. wafer area and integrable with CMOS electronics, CMOS compatible aluminum nitride (AlN)‐ and scandium aluminum nitride (ScAlN)‐based pyroelectric detectors are developed for sensing of CO2and CH4gases, which are two of the greenhouse gases that contribute significantly to global warming. Leveraging gas absorption at respective mid‐infrared (IR) wavelengths, CO2 and CH4 gases are detected at various concentrations with fast response time ≈1 s. A compound parabolic collector (CPC) is designed and integrated into the gas sensor to enhance the optical flux received by the detector, which demonstrates ≈10× signal improvement in its presence. Further factors such as the effect of sensing area reduction and response to random gas concentrations are also tested on AlN‐ and ScAlN‐based pyroelectric detectors respectively to observe the gas sensing behaviors of both detectors. The results obtained provide further understanding of the behavior of CMOS AlN‐ and ScAlN‐based pyroelectric detectors as IR gas sensors, which can potentially inspire new design and design selection for various gas sensing applications. [ABSTRACT FROM AUTHOR]

CsCu2I3 crystal is a promising Cu-based halide material for scintillation detection. In this paper, Na+ ion-doped CsCu2I3 crystals with a size of ϕ12 mm × 50 mm were grown successfully using the vertical Bridgman method, and the properties were systematically investigated. CsCu2I3:Na crystals exhibit yellow light emission peaking at 575 nm and a large Stokes shift of 1.55 eV. Based on the results of the XRD and XPS, the Na+ was introduced successfully. The optical absorption spectra show that the band gap of CsCu2I3 crystals was narrowed when the Na+ was doped. The photoluminescence quantum efficiency (PLQY) is improved from 16.4% to 19.6%. Finally, the X-ray-induced afterglow, and scintillation (energy resolution, light yield and decay time) under a 137Cs source were measured and discussed. These results illustrate that CsCu2I3:Na crystals have potential applications in the radiation detection field. [ABSTRACT FROM AUTHOR]

This work reports morphologically alike, high-quality monolayer MoS2 flakes with a similar strain at various growth temperatures (750–900°C) achieved by adjusting sulfur temperature. The growth dynamics of MoS2 are correlated with changes in the photoluminescence (PL) and Raman peak positions. Monolayer MoS2 crystals are synthesized at different growth temperatures from 750°C to 900°C using chemical vapor deposition (CVD). We examined the structural quality and aimed to extract the recombination mechanisms in MoS2 using low-temperature, variable, and low-laser-intensity PL measurements. Our studies of the defect-associated bound exciton emission are well correlated with the blueshift in the A1g mode of Raman spectra, blueshift in PL spectra, and x-ray photoelectron spectroscopy results for crystal grown at 900°C. Our research findings not only shed light on a thorough, non-intrusive method for modifying growth parameters to enhance optical performance, but they also suggest a way to modify the optical characteristics of MoS2 while maintaining the morphology. [ABSTRACT FROM AUTHOR]

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Abstract Single‐component metal halides with white light emission are highly attractive for solid‐state lighting applications, but it is still challenging to develop all‐inorganic lead‐free metal halides with high white‐light emission efficiency. Herein, by rationally introducing silver (Ag) into zero‐dimensional (0D) Cs3Cu2Br5 as new structural building unit, a one‐dimensional (1D) bimetallic halide Cs6Cu3AgBr10 is designed that emits strong warm‐white light with an impressive photoluminescence quantum yield (PLQY) of 94.5% and excellent stability. This structural transformation lowers the conduction band minimum while maintaining the localized nature of the valence band maximum, which is crucial in expanding the excitation spectrum and obtaining efficient self‐trapped excitons (STEs) emission simultaneously. Detailed spectroscopy studies reveal that the white‐light originates from triplet STEs emission, which can be remarkably improved by weakening the strong electron‐phonon coupling and thus suppressing phonon‐induced non‐radiative processes. Moreover, the interesting temperature‐dependent emission behavior, together with self‐absorption‐free property, make Cs6Cu3AgBr10 as sensitive luminescent thermometer and high‐performance X‐ray scintillator, respectively. These findings demonstrate a general approach to achieving effective single‐component white‐light emitters based on lead‐free, all‐inorganic metal halides, thereby opening up a new avenue to explore their versatile applications such as lighting, temperature detection and X‐ray imaging.

Background: Positron emission tomography (PET) requires a high signal-to-noise ratio (SNR) to improve image quality, with time-of-flight (TOF) being an effective way to boost the SNR. However, the scanner sensitivity and resolution must be maintained. The use of axially aligned 100-mm LYSO:Ce,Ca scintillation crystals with double-sided readout has the potential of ground-breaking TOF and sensitivity, while reducing parallax errors through depth-of-interaction (DOI) estimation, and also allowing a reduction in the number of readout channels required, resulting in cost benefits. Due to orientation, these fibres may also facilitate the integration of TOF-PET with magnetic resonance imaging (MRI) in hybrid imaging systems. The challenge of achieving a good spatial resolution with such long axial fibres is directly related to the achievable TOF resolution. In this study, the timing performance and DOI resolution of emerging high-performance materials were investigated to assess the merits of this approach in organ-dedicated or total-body/large-scale PET imaging systems. Methods: LYSO:Ce,Ca scintillation fibres of 20 mm and 100 mm length were tested in various operating and readout configurations to determine the best achievable coincidence time resolution (CTR) and DOI resolution. The tests were performed using state-of-the-art high-frequency (HF) readout and commercially available silicon photomultipliers (SiPMs) from Broadcom Inc. Results: For the 100-mm fibre, an average CTR performance of 137 ± 1 ps FWHM and an average depth-of-interaction resolution within the fibre of 12.3 ± 0.5 mm FWHM could be obtained. The 20-mm fibre showed a sub-100 ps CTR of 98 ± 1 ps FWHM and a fibre resolution of 8.5 ± 0.2 mm FWHM in the double-sided readout configuration. Conclusion: With modern SiPMs and crystals, a double-sided readout of long fibres can achieve excellent timing resolution and field-advancing TOF resolution, outperforming commercial PET systems. With 100-mm fibres, an electronic channel reduction of about a factor 2.5 is inherent, with larger reduction factors conceivable, which can lead to lower production costs. The spatial resolution was shown to be limited in the axial direction with 12 mm, but is defined to 3 mm in all other directions. Recent SiPM and scintillator developments are expected to improve on the time and spatial resolution to be investigated in future prototypes. [ABSTRACT FROM AUTHOR]

Scintillating screens for X-ray imaging applications are prepared with various methods. Among them, the classic sedimentation method presents certain weak points. In this context, a novel fabrication process was developed that offers simplicity, economy of resources and time, while the screens exhibit adequate durability and image quality performance. The proposed technique involves a resin mixture that contains the phosphor in powder form (Gd2O2S:Tb in the present work) and graphite. The novel method was optimized and validated by coupling the screens to a complementary metal oxide semiconductor (CMOS) X-ray sensor. Indicatively, screens of two surface densities were examined; 34 mg/cm2 and 70 mg/cm2. Various established image quality metrics were calculated following the IEC 62220-1 international standard, including the detective quantum efficiency (DQE). Comparisons were carried out under the same conditions, with a sedimentation screen reported previously and a screen of wide commercial circulation (Carestream Min-R 2190). The novel screens exhibit has comparable or even better performance in image-quality metrics. The 34 mg/cm2 screen achieves a DQE 15–20% greater than its comparison counterpart, and its limiting resolution was 5.3 cycles/mm. The detector coupled to the 70 mg/cm2 screen achieved a DQE 10–24% greater than its own counterpart, and its limiting resolution was found to be 5.4 cycles/mm. [ABSTRACT FROM AUTHOR]

This study aims to determine the optimum composition of the CeBr1−xIx compound to achieve the maximum light output. It is based on calculations of the band energy structure of crystals, specifically taking into account the characteristics of the mutual location of local and band 5d states of the Ce3+ ions. The band energy structures for CeBr2I and CeBrI2 crystals were calculated using the projector augmented wave method. The valence band was found to be formed by the hybridized states of 4p Br and 5p I. The 4f states of Ce3+ are located in the energy forbidden band gap. The conduction band is formed by the localized 5d1 states, which are created by the interaction between the 5d states of Ce3+ and the 4f0 hole of the cerium ion. The higher-lying delocalized 5d2 states of Ce3+ correspond to the energy levels of the 5d states of Ce3+ in the field of the halide Cl0 (Br0) hole. The relative location of 5d1 and 5d2 bands determines the intensity of 5d–4f luminescence. The bottom of the conduction band is formed by localized 5d1 states in the CeBr2I crystal. The local character of the bottom of the conduction band in the CeBr2I crystal favors the formation of self-trapped Frenkel excitons. Transitions between the 5d1 and 4f states are responsible for 5d–4f exciton luminescence. In the CeBrI2 crystal, the conduction band is formed by mixing the localized 5d1 and delocalized 5d2 states, which leads to quenching the 5d–4f luminescence and a decrease in the light output despite the decrease in the forbidden band gap. CsBr2I is the optimum composition of the system to achieve the maximum light output. [ABSTRACT FROM AUTHOR]

Background: Many computational methods have been developed to detect non-reference transposable element (TE) insertions using short-read whole genome sequencing data. The diversity and complexity of such methods often present challenges to new users seeking to reproducibly install, execute, or evaluate multiple TE insertion detectors. Results: We previously developed the McClintock meta-pipeline to facilitate the installation, execution, and evaluation of six first-generation short-read TE detectors. Here, we report a completely re-implemented version of McClintock written in Python using Snakemake and Conda that improves its installation, error handling, speed, stability, and extensibility. McClintock 2 now includes 12 short-read TE detectors, auxiliary pre-processing and analysis modules, interactive HTML reports, and a simulation framework to reproducibly evaluate the accuracy of component TE detectors. When applied to the model microbial eukaryote Saccharomyces cerevisiae, we find substantial variation in the ability of McClintock 2 components to identify the precise locations of non-reference TE insertions, with RelocaTE2 showing the highest recall and precision in simulated data. We find that RelocaTE2, TEMP, TEMP2 and TEBreak provide consistent estimates of ∼ 50 non-reference TE insertions per strain and that Ty2 has the highest number of non-reference TE insertions in a species-wide panel of ∼ 1000 yeast genomes. Finally, we show that best-in-class predictors for yeast applied to resequencing data have sufficient resolution to reveal a dyad pattern of integration in nucleosome-bound regions upstream of yeast tRNA genes for Ty1, Ty2, and Ty4, allowing us to extend knowledge about fine-scale target preferences revealed previously for experimentally-induced Ty1 insertions to spontaneous insertions for other copia-superfamily retrotransposons in yeast. Conclusion: McClintock (https://github.com/bergmanlab/mcclintock/) provides a user-friendly pipeline for the identification of TEs in short-read WGS data using multiple TE detectors, which should benefit researchers studying TE insertion variation in a wide range of different organisms. Application of the improved McClintock system to simulated and empirical yeast genome data reveals best-in-class methods and novel biological insights for one of the most widely-studied model eukaryotes and provides a paradigm for evaluating and selecting non-reference TE detectors in other species. [ABSTRACT FROM AUTHOR]

The objective of this paper is to review the use of the thermoluminescence (TL) and optically stimulated luminescence (OSL) techniques as research tools in luminescence, particularly to detect the presence of trapping centers that can degrade the efficiency of scintillators, and shape the properties of persistent phosphors, storage phosphors and dosimeters. A brief review of the main analysis techniques is provided, followed by a discussion of their limitations. Examples of applications in which the TL or OSL analyses have provided useful information on the trapping and recombination of charges created by ionizing radiation is given. [ABSTRACT FROM AUTHOR]

X‐ray imaging technology is critical to numerous different walks of daily life, ranging from medical radiography and security screening all the way to high‐energy physics. Although several organic chromophores are fabricated and tested as X‐ray imaging scintillators, they generally show poor scintillation performance due to their weak X‐ray absorption cross‐section and inefficient exciton utilization efficiency. Here, a singlet fission‐based high‐performance organic X‐ray imaging scintillator with near unity exciton utilization efficiency is presented. Interestingly, it is found that the X‐ray sensitivity and imaging resolution of the singlet fission‐based scintillator are dramatically improved by an efficient energy transfer from a thermally activated delayed fluorescence (TADF) sensitizer, in which both singlet and triplet excitons can be efficiently harnessed. The fabricated singlet fission‐based scintillator exhibits a high X‐ray imaging resolution of 27.5 line pairs per millimeter (lp mm−1), which exceeds that of most commercial scintillators, demonstrating its high potential use in medical radiography and security inspection. [ABSTRACT FROM AUTHOR]

An experiment to search for 2ε-, εβ+ - and 2β+ -decays of 106Cd, using a 215 g cadmium tungstate scintillation crystal enriched at 66 % by 106Cd (106CdWO4) is carried out at the Gran Sasso underground laboratory (Italy). Events in the 106CdWO4 detector are recorded in (anti)coincidences with two large-volume CdWO4 scintillation counters. The design of the detector system, calibration and background measurements, methods, and results of data analysis to determine key detector characteristics are described. The experimental data are compared with Monte Carlo simulation results, and a background model is constructed. The radioactive contamination of the setup components is studied. The sensitivity of the experiment approaches the level of theoretical predictions for the 2Vεβ + -decay channel, while for other possible 2β-decay channels it is already on the level of lim T1/2 ~ 1021 - 1022 years. [ABSTRACT FROM AUTHOR]

X-ray radiography and computed tomography have become well-established methods for investigation of internal structure of objects and for defectoscopy. Recently, the methods have even been used for in-situ analysis of materials under mechanical loading. Although the techniques would be very suitable for analysis during dynamic events, their application is constrained by typical achievable frame rates. Therefore, fast imaging is usually limited to facilities providing sufficient flux like particle accelerators. In this paper, we test imaging performance of a laboratory-based setup with a high-power X-ray tube, a scintillation panel, and an optical camera. Fast-rotating object and typical specimens for impact testing are irradiated with different power settings and quality of captured images is evaluated and analyzed. It is found out that the system can be successfully used for imaging at several hundred frames per second allowing for inspection of slow impact dynamics experiments. [ABSTRACT FROM AUTHOR]

In comparison with single crystal scintillators, glass scintillators are more promising materials for their benefits of easy preparation, low cost, controllable size, and large-scale manufacture. The emission of Eu3+ ion at 612 nm matches well with the photoelectric detector, making it suitable for the activator in glass scintillators. Therefore, the research on Eu3+ doped glass scintillators attract our attention. The photoluminescent and scintillating properties of Eu3+-activated boroaluminosilicate glass scintillators prepared by the conventional melt-quenching method were investigated in this work. The glass samples present good internal quantum yield. Under X-ray radiation, the optimal sample reveals high X-ray excited luminesce (XEL), and its integrated intensity of XEL is 22.7% of that of commercial crystal scintillator Bi4Ge3O12. Furthermore, the optimal specimen possesses a spatial resolution of 14 lp/mm in X-ray imaging. These results suggest that Eu3+-doped boroaluminosilicate glass is expected to be applied in X-ray imaging. [ABSTRACT FROM AUTHOR]

Eulytite-type Ba3RE(PO4)3 (RE = Y, La, and Lu) single crystals were synthesized by the floating zone method, and their scintillation properties were investigated. The powder X-ray diffraction measurement revealed that the single phase of Ba3RE(PO4)3 samples were successfully synthesized. The samples exhibited a luminescence peak due to self-trapped exciton at around 400 nm under vacuum ultraviolet and X-ray irradiation. The X-ray-induced scintillation decay time constants of the samples were several microseconds at room temperature. In the 241Am α-ray irradiated pulse height spectra, all the samples showed a clear full energy peak, and the absolute light yields of the Ba3Y(PO4)3, Ba3La(PO4)3, and Ba3Lu(PO4)3 single crystals were estimated to be 960, 1160, and 1220 ph/5.5 MeV-α, with a typical error of ±10%, respectively. The scintillation light yields of the Ba3RE(PO4)3 have been quantitatively clarified for the first time. [ABSTRACT FROM AUTHOR]

The high energy neutron generation facilities worldwide uses the Li(p,n) system for production of the quasi mono-energetic neutrons from epithermal to few hundreds of MeV. Among the facilities either self-standing thick Li target or Li foil supported on a target assembly is used. In case of a supported Li target, either low or high mass supporting substrates like Al, C, Au, Ta etc. can be used. However, the neutron emission from the supporting substrate can interfere with the Li(p,n) reaction neutrons. In the present study neutron yields from a thin natural Li target supported on the thick natural Ta (high Z) and C (low Z) targets were measured at incident proton energies between 8-20 MeV. The proton irradiation of targets were performed at the Pelletron accelerator Facility, Mumbai and the emitted neutrons were measures at both forward (0°) and lateral (90°) directions with respect to the incident beam. The neutron yield was estimated using the CR-39 detectors and dual scintillator based active neutron spectrometer. A neutron dose equivalent (NDE) meter was also used to measure the neutron ambient dose equivalent at the measurement point. Experimentally measured neutron yields and ambient neutron dose equivalent estimates indicated higher Li(p,n) neutron yield with carbon as the supporting substrate. This is due to fewer self-emissions from natC compared to natTa target. Carbon supporting substrate also ensures improved spectral features of the Li(p,n) emission neutrons and lesser neutron fluence around the source location. This ensures efficient implementation of radiation protection practices with carbon target due to lower neutron fluence around the source compared to tantalum target. Carbon is a favorable supporting substrate compared to high Z-metal targets like Ta for emission neutron studies on Li target at proton energies between 8-20 MeV. [ABSTRACT FROM AUTHOR]

To reduce the issue of tri-primary color reabsorption, a new approach for single-phase phosphors as light-emitting diodes (LEDs) has been recommended. The structures, morphology, photoluminescence, thermal stability, and luminescence mechanism of a variety of Ca3Bi (PO4)3 (CBPO): Ce3+/Dy3+ phosphors were investigated. XRD characterization showed that all CBPO samples were eulytite structures. Furthermore, the energy transfer process from Ce3+ to Dy3+ in CBPO is systematically investigated in this work, and the color of light can be adjusted by changing the ratio of doped ions. Under UV light, energy is transferred from Ce3+-Dy3+ mainly through quadrupole-quadrupole interactions in the CBPO host, and doping with different Dy3+ concentrations tunes the emission color from blue to white. The thermal stability of the CBPO: 0.04Ce3+, 0.08Dy3+ samples is outstanding, and the CIE coordinates of the samples after emission have little effect with temperature, while their emission intensity at 423 K is as strong as that at room temperature, reaching 90%. The above results indicate that this CBPO material has great potential as a white light phosphor under near-UV excitation at the optimized concentration of Ce3+ and Dy3+. [ABSTRACT FROM AUTHOR]

Synovial fluid (SF) from human knee joints with osteoarthritis (OA) has elevated levels of lysophosphatidylcholine (LPC) species, but their functional role is not well understood. This in vitro study was designed to test the hypothesis that various LPCs found elevated in OA SF and their metabolites, lysophosphatidic acids (LPAs), modulate the abundance of proteins and phospholipids (PLs) in human fibroblast-like synoviocytes (FLSs), with even minute chemical variations in lysophospholipids determining the extent of regulation. Cultured FLSs (n = 5–7) were treated with one of the LPC species, LPA species, IL-1β, or a vehicle. Tandem mass tag peptide labeling coupled with LC-MS/MS/MS was performed to quantify proteins. The expression of mRNA from regulated proteins was analyzed using RT-PCR. PL synthesis was determined via ESI-MS/MS, and the release of radiolabeled PLs was determined by means of liquid scintillation counting. In total, 3960 proteins were quantified using multiplexed MS, of which 119, 8, and 3 were significantly and reproducibly regulated by IL-1β, LPC 16:0, and LPC 18:0, respectively. LPC 16:0 significantly inhibited the release of PLs and the synthesis of phosphatidylcholine, LPC, and sphingomyelin. Neither LPC metabolite—LPA 16:0 nor LPA 18:0—had any reproducible effect on the levels of each protein. In conclusion, small chemical variations in LPC species can result in the significantly altered expression and secretion of proteins and PLs from FLSs. IL-1β influenced all proteins that were reproducibly regulated by LPC 16:0. LPC species are likely to modulate FLS protein expression only in more advanced OA stages with low IL-1β levels. None of the eight proteins being significantly regulated by LPC 16:0 have been previously reported in OA. However, our in vitro findings show that the CD81 antigen, calumenin, and B4E2C1 are promising candidates for further study, focusing in particular on their potential ability to modulate inflammatory and catabolic mechanisms. [ABSTRACT FROM AUTHOR]

MALTA is part of the Depleted Monolithic Active Pixel sensors designed in Tower 180 nm CMOS imaging technology. A custom telescope with six MALTA planes has been developed for test beam campaigns at SPS, CERN, with the ability to host several devices under test. The telescope system has a dedicated custom readout, online monitoring integrated into DAQ with realtime hit map, time distribution and event hit multiplicity. It hosts a dedicated fully configurable trigger system enabling to trigger on coincidence between telescope planes and timing reference from a scintillator. The excellent time resolution performance allows for fast track reconstruction, due to the possibility to retain a low hit multiplicity per event which reduces the combinatorics. This paper reviews the architecture of the system and its performance during the 2021 and 2022 test beam campaign at the SPS North Area. [ABSTRACT FROM AUTHOR]

A brief review of the transport and galvanomagnetic properties of an electron-doped Nd2 –xCexCuO4 layered superconductor with an emphasis on the role of the structure of Josephson vortices formed in the crystal in a magnetic field oriented in the parallel direction to the CuO2 planes is given. The experimental data on the longitudinal and Hall magnetoresistance of the recently synthesized Nd2 –xCexCuO4/SrTiO3 epitaxial films are analyzed. The possibility of formation of a system of Josephson vortices in this highly anisotropic system is determined by the unique orientation of the c axis and the conducting CuO2 planes of the Nd2 –xCexCuO4 compound with respect to the substrate plane. [ABSTRACT FROM AUTHOR]

tomatic search for the most contrast images using a given reference, the experimental data for which were obtained using the analytical technique of X-ray phase contrast imaging. The projections of the biological object were obtained by applying free space propagation of coherent radiation when no additional optical elements are placed between the sample and the detector equipped with a YAG:Ce scintillator to exploit the interference effects characteristic of the method due to the high-intensity characteristics of the X-ray light of the SOLEIL synchrotron. The energy of the X-ray photons was 10 keV, and the distance between the sample and the detector was 16.5 cm. We consider the use of standard Matlab tools for algorithmic correction of inhomogeneities of the detector and probing light beam used to build an image of the internal structure of the object and to evaluate the contrast of a group of images, by choosing such common quality criteria as PSNR and SSIM. The program is able to generate such a set of images depending on the parameters entered by the user for a subjective search for contrast images. Numerical estimates well confirm the visual results of the algorithmic search and allow us to reach the most informative image from the generated array, which is created by the user using the interface. The aim of this work is to familiarize with the use of the developed software product and the concept of semi-automatic search among the dataset of digital phase-contrast images. [ABSTRACT FROM AUTHOR]

The luminescent Z-scan technique with time resolution is applied to the study of the luminescence properties of CH3NH3PbBr3 single crystals representative of the family of hybrid organic–inorganic lead perovskites successfully applied recently in photovoltaics and currently investigated as potential nanosecond scintillators. The third harmonic of Ti-sapphire laser (λ = 266 nm) with a pulse duration of 26 fs and 1 kHz frequency was applied for the luminescence excitation creating the charge carriers with the estimated density from 1017 to 1021 cm−3 in the temperature range from 13 to 300 K. Temperature and excitation density dependence of the luminescence yield and kinetics is interpreted with the consideration of the temperature-dependent binding of electrons and holes into excitons, a saturation of defects responsible for the non-radiative relaxation channel competing with exciton creation; absorption saturation resulting in the increased penetration depth of the excitation radiation and hence the increased contribution of the re-absorption. [ABSTRACT FROM AUTHOR]

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Atomic Energy Science & Technology is the property of Editorial Board of Atomic Energy Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A liquid scintillator consisting of linear alkylbenzene as the solvent and 2,5-diphenyloxazole as the fluor was developed for the SNO+ experiment. This mixture was chosen as it is compatible with acrylic and has a competitive light yield to pre-existing liquid scintillators while conferring other advantages including longer attenuation lengths, superior safety characteristics, chemical simplicity, ease of handling, and logistical availability. Its properties have been extensively characterized and are presented here. This liquid scintillator is now used in several neutrino physics experiments in addition to SNO+.