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Let R be any real closed field expanded by some o-minimal structure. Let f : A → Rd be a definable and continuous mapping defined on a definable, closed, bounded subset A of Rn. Let E be a finite family of definable subsets of Rn contained in A. Let p be any positive integer. We prove that then there exists a finite simplicial complex T in Rn and a definable homeomorphism h :|T| → A, where |T| := υT, such that for each simplex Δ ∈ T, the restriction of h to its relative interior ... is a Cp-embedding of ... into Rn and moreover both h and f o h are of class Cp in the sense that they have definable Cp-extensions defined on an open definable neighborhood of |T| in Rn. We then call a pair (T, h) a strict Cp-triangulation of A. In addition, this triangulation can be made compatible with E in the sense that for each E ∈ E, h-1(E) is a union of some ... where Δ ∈ T. We also give an application to approximation theory. [ABSTRACT FROM AUTHOR]

Copyright of Nuclear Safety is the property of Nuclear & Radiation Safety Center 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.)

Direct X-ray detectors based on semiconductors have drawn great attention from researchers in the pursuing of higher imaging quality. However, many previous works focused on the optimization of detection performances but seldomly watch them in an overall view and analyze how they will influence the detective quantum efficiency (DQE) value. Here, we propose a numerical model which shows the quantitative relationship between DQE and the properties of X-ray detectors and electric circuits. Our results point out that pursuing high sensitivity only is meaningless. To reduce the medical X-ray dose by 80%, the requirement for X-ray sensitivity is only at a magnitude of 103 μCGy−1⋅cm−2. To achieve the DQE = 0.7 at X-ray sensitivity air from 1248 to 8171 μCGy−1air⋅cm−2, the requirements on dark current density ranges from 10 to 100 nA⋅cm−2 and the fluctuation of current density should fall in 0.21 to 1.37 nA⋅cm−2. [ABSTRACT FROM AUTHOR]

Experimental activities involving multi-TeV muon collisions are a relatively recent endeavor. The community has limited experience in designing detectors for lepton interactions at center-of-mass energies of 10 TeV and beyond. This review provides a short overview of the machine characteristics and outlines potential sources of beam-induced background that could affect the detector performance. The strategy for mitigating the effects of the beam-induced background on the detector at TeV is discussed with a focus on the machine–detector interface, detector design, and implementation of reconstruction algorithms. The physics potential at this center-of-mass energy is evaluated using a detailed detector simulation that incorporates the effects of the beam-induced background. This evaluation concerns the Higgs boson couplings and the Higgs field potential sensitivity, which then are used to obtain confidence on the expectations at 10 TeV. The physics and detector requirements for an experiment at TeV, outlined here, form the foundation for the initial detector concept at that center-of-mass energy. [ABSTRACT FROM AUTHOR]

A position-sensitive detector, which is a neutron target at the same time, is presented to study the interaction reactions of fast neutrons of above 1 MeV with light nuclei, in particular, with the 10B nucleus. It contains two boron-10 layers and a system of wire electrodes to identify secondary nuclei, in particular 3H and 4He, and to determine energy loss and departure angle. Thus the neutron energy can be determined. [ABSTRACT FROM AUTHOR]

Chips caught in the shank during automatic tool change on a machining center can cause runout of the tool and affect machining accuracy. To accurately measure the runout amount, the center position of the tool was calculated using the least-squares method and filter processing, taking into account the measurement error of the sensor, the runout amount of the spindle itself, and the variation in the individual dimensions of each tool. As a result, the runout of the tool was detected with high speed and accuracy, enabling automatic operation to be stopped before the start of the next machining process. [ABSTRACT FROM AUTHOR]

In positron emission tomography (PET), measurements of depth-of-interaction (DOI) information and time-of-flight (TOF) information are important. DOI information reduces the parallax error, and TOF information reduces noise by measuring the arrival time difference of the annihilation photons. Historically, these have been studied independently, and there has been less implementation of both DOI and TOF capabilities because previous DOI detectors did not have good TOF resolution. However, recent improvements in PET detector performance have resulted in commercial PET scanners achieving a coincidence resolving time of around 200 ps, which result in an effect even for small objects. This means that TOF information can now be utilized even for a brain PET scanner, which also requires DOI information. Therefore, various methods have been proposed to obtain better DOI and TOF information. In addition, the cost of PET detectors is also an important factor to consider, since several hundred detectors are used per PET scanner. In this paper, we review the latest DOI–TOF detectors including the history of detector development. When put into practical use, these DOI–TOF detectors are expected to contribute to the improvement of imaging performance in brain PET scanners. [ABSTRACT FROM AUTHOR]

Abstract Direct X-ray detectors based on semiconductors have drawn great attention from researchers in the pursuing of higher imaging quality. However, many previous works focused on the optimization of detection performances but seldomly watch them in an overall view and analyze how they will influence the detective quantum efficiency (DQE) value. Here, we propose a numerical model which shows the quantitative relationship between DQE and the properties of X-ray detectors and electric circuits. Our results point out that pursuing high sensitivity only is meaningless. To reduce the medical X-ray dose by 80%, the requirement for X-ray sensitivity is only at a magnitude of 103 μCGy−1⋅cm−2. To achieve the DQE = 0.7 at X-ray sensitivity air from 1248 to 8171 μCGy−1 air⋅cm−2, the requirements on dark current density ranges from 10 to 100 nA⋅cm−2 and the fluctuation of current density should fall in 0.21 to 1.37 nA⋅cm−2. Graphical Abstract

As lead halide perovskite (LHP) semiconductors have shown tremendous promise in many application fields, and particularly made strong impact in the solar photovoltaic area, low dimensional quantum dot forms of these perovskites are showing the potential to make distinct marks in the fields of electronics, optoelectronics and photonics. The so-called perovskite quantum dots (PQDs) not only possess the most important features of LHP materials, i.e., the unusual high defect tolerance, but also demonstrate clear quantum size effects, along with exhibiting desirable optoelectronic properties such as near perfect photoluminescent quantum yield, multiple exciton generation and slow hot-carrier cooling. Here, we review the advantageous properties of these nanoscale perovskites and survey the prospects for diverse applications which include light-emitting devices, solar cells, photocatalysts, lasers, detectors and memristors, emphasizing the distinct superiorities as well as the challenges.

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office 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.)

To study the cluster structure of light nuclei in the reactions of interaction of fast neutrons with the 9Be nucleus, the kinematics of the reactions n +9Be → α + 6He and n +9Be → 8Be + 2n → 2α + 2n at energies of 1–3 MeV were modeled. It was shown that the characteristics of reaction channels in the interaction of a neutron with a 9Be nucleus can be found by measuring the ionization losses of charged reaction fragments in a multilayer gas-filled charged particle detector with a beryllium converter. [ABSTRACT FROM AUTHOR]

In the present article, a methodology has been discussed to evaluate the influence of activity concentration of soil samples containing heavy metals in the environment. The approach leverages a simulated germanium detector and a cylindrical geometry sample configuration to analyse soil samples with varying densities. The results showed a positive correlation between the soil densities and activity concentration, with an average correlation coefficient of 0.99 indicating that variations in density affect the activity concentration measurements. To mitigate this error, a demonstration of the self-absorption correction as a function of density, being an essential part of the present study has been included. [ABSTRACT FROM AUTHOR]

Lateral flow immunochromatography assay is a new instantaneous detection technology that employs a chromatographic membrane and labeling materials for detection. This detection technology is convenient, fast, and inexpensive, and is therefore widely used in a number of different fields, such as biomedicine, disease detection, food safety, environmental protection, and so on. Traditional lateral flow immunochromatography assay relied on visual observation and provided only qualitative or semi-quantitative results. By utilizing various types of markers and sensitive detection devices, lateral flow immunochromatography assay enables quantitative and multi-component detection of the analytes. The research progress on the lateral flow immunoassay detection system and its current applications in the context of recognition elements, labeling materials, and detection instruments were reviewed in this paper. [ABSTRACT FROM AUTHOR]

Machine learning tools capable of identifying animals by sound have proliferated, making the challenge of interpreting their outputs much more prevalent. These tools, like their predecessors, quantify prediction uncertainty with scores that tend to resemble probabilities but are actually unitless scores that are (generally) positively related to prediction accuracy in species-specific ways. BirdNET is one such tool, a freely available animal sound identification algorithm capable of identifying > 6,000 species, most of them birds. We describe two ways in which BirdNET "confidence scores"—and the output scores of other detector tools—can be used appropriately to interpret BirdNET results (reviewing them down to a user-defined threshold or converting them to probabilities), and provide a step-by-step tutorial to follow these suggestions. These suggestions are complementary to common performance metrics like precision, recall, and receiver operating characteristic. BirdNET can be a powerful tool for acoustic-based biodiversity research, but its utility depends on the careful use and interpretation of its outputs. [ABSTRACT FROM AUTHOR]

The 3 He(n, p) process is excellent for neutron detection between thermal and ∼ 4 MeV because of the high cross section and near-complete energy transfer from the neutron to the proton. Traditional gaseous 3 He detectors using this process typically have high levels of radiogenic backgrounds so that they cannot measure the small neutron fluxes present in underground laboratories for dark matter experiments. I propose a cryogenic liquid 3 He detector that can be designed with tiny radiogenic backgrounds and efficiently measure neutron fluxes in low-flux environments. [ABSTRACT FROM AUTHOR]

We always face water leakage problems in underground distribution water networks (DWNs). Existing leak detectors suffer from false alarms due to poor leak signal quality affected by external noise, often collected by acoustic or vibratory sensors. This paper introduces a novel Discrete Wavelet Transform Detector (DWTD) that leverages precise pressure signals non-influenced by environmental noise. Using a prototype of a 100m PEHD pipeline and a diameter of 40mm, Data from two pressure transmitters were collected using a dSPACE MicroLabBox unit. The main idea is to apply the Discrete Wavelet Transform (DWT) with a DONOHO threshold law to cancel noises due to water turbulence fluctuations, ensuring high-quality signals for accurate leak detection and localization. As benchmarks to assess the quality of denoising signals three parameters were calculated, Signal to Noise Ratio (SNR > 26.6763 dB), Normalized Cross-Correlation (NCC≈1), and Mean Square Error (0.20573 < MSE < 48.4761). The denoised temporal signals are obtained from the Inverse Discrete Wavelet Transform (IDWT). A Cross-correlation is employed to these signals to determine the leak's location. The experimental validation involves positioning the first and second transmitters at specific distances on both sides of the leak position. This allows for comparison between the actual leak position in advance known and calculated positions at various points and leak sizes. With only a few exceptions where the maximum error rate reached 5 meters from the actual leak position, the detector's effectiveness was proven across tests involving four different leak sizes. [ABSTRACT FROM AUTHOR]

In this paper, the development of action and event detectors over the past three decades is summarized. The detectors are divided into 2D detectors, 3D detectors and deep learning detectors according to whether they contain spatial information and whether they use deep learning. This paper briefly introduces the typical detectors of the different types mentioned above, and explains the advantages, disadvantages and characteristics respectively, and compares them. Comparing traditional feature detection methods with ones based on deep learning, we found that the method of first detecting microscopic details such as point, line, surface angle, etc., and then performing action and event recognition is no longer the mainstream of current research. Due to the strong generalization ability, end-to-end action and event recognition methods based on deep learning perform better than traditional methods. Finally, this paper proposes three research directions for action recognition and event recognition based on feature detectors. [ABSTRACT FROM AUTHOR]

Microwave detectors play a crucial role in modern technological applications, but traditional detectors suffer from limited functionality, limited detection accuracy, and difficulties in large‐scale deployment. This study proposes a dual‐function microwave detector based on metamaterials, capable of simultaneously measuring microwave power and polarization angle. The detector consists of a metal disc with 12 concave grooves, a dielectric layer, a metal reflector, and a resistive network. The designed detector achieves efficient absorption of 93.54% of microwave energy, with 75.4% dissipated in the resistive component and converted into heat. By detecting the temperature using a thermocouple thermometer, the incoming wave power can be determined, and by discriminating between different resistive temperatures, the polarization angle of the incoming wave can be identified. Simulation and experimental results demonstrate the outstanding detection efficiency and stability of this detector. It exhibits a linear response to different incident power densities and polarization angles, showing potential application value in the field of microwave wireless power transmission. [ABSTRACT FROM AUTHOR]

Analyzing the isotopic composition of cosmic rays (CRs) provides valuable insights into the galactic environment and helps refine existing propagation models. A particular interest is devoted to secondary-to-primary ratios of light isotopic components of CRs, the measurement of which can provide complementary information with respect to secondary-to-primary ratios like B/C. Given the complexity of the concurrent measurement of velocity and momentum required to differentiate isotopes of the same Z, a task typically accomplished using magnetic spectrometers, existing measurements of these ratios only effectively characterize the low-energy region (below 1 GeV/nucl). This study introduces a novel technique for isotopic distinction in CRs at high energies up to 100 GeV/nucl based on multiple scattering, which, combined with the proposed measurement of velocity, represent an interesting alternative to magnetic spectrometers. The performance of this technique was assessed through a dedicated simulation using the GEANT4 package, with specific emphasis on Z = 1 isotopes. [ABSTRACT FROM AUTHOR]

Analyzing the isotopic composition of cosmic rays (CRs) provides valuable insights into the galactic environment and helps refine existing propagation models. A particular interest is devoted to secondary-to-primary ratios of light isotopic components of CRs, the measurement of which can provide complementary information with respect to secondary-to-primary ratios like B/C. Given the complexity of the concurrent measurement of velocity and momentum required to differentiate isotopes of the same Z, a task typically accomplished using magnetic spectrometers, existing measurements of these ratios only effectively characterize the low-energy region (below 1 GeV/nucl). This study introduces a novel technique for isotopic distinction in CRs at high energies up to 100 GeV/nucl based on multiple scattering, which, combined with the proposed measurement of velocity, represent an interesting alternative to magnetic spectrometers. The performance of this technique was assessed through a dedicated simulation using the GEANT4 package, with specific emphasis on Z = 1 isotopes.

X-ray applications in imaging and beyond require efficient and optimal detectors. Energy separation, time loss, and manufacturing cost are among the features that led us to design a semiconductor detector. A low-gain avalanche diode (LGAD) with internal amplification allows, in a sufficient field, the internal propagation process by accelerating the carriers, the energy required for ionization, and the generation of secondary carriers to produce a better gain (higher signal-to-noise ratio) and also provide more time efficiency (in the range of nanoseconds). In this article, we simulate the LGAD silicon detector with Silvaco software by applying reverse bias voltage and radiation in the range of visible light to X-ray. Newton and Gummel's methods were used. In Newton's method, one of the mechanisms of radiation interaction with matter is considered variable and the rest are fixed. However, in Gummel's method, all mechanisms are solved simultaneously. In the X-ray wavelength range, the electron current in this detector is 10-4 amperes, and this current decreases with increasing energy. The dark current is 10-6 amperes. By applying visible light with 0.45-micrometer wavelength and 1 V/cm2 intensity, the detector current was obtained about 6.5×10-4 amperes. For 1.0×10-5 x-ray wavelength and 108 V/cm2 intensity, detector current was obtained about 3.5×10-4 amperes. Considering the quick response time of this detector and the current in the range of microamps, this detector is a suitable option for X-ray detection. Also, this detector shows superior performance in the visible light range.

Purpose: Single‐isocenter multi‐target intracranial stereotactic radiotherapy (SIMT) is an effective treatment for brain metastases with complex treatment plans and delivery optimization necessitating rigorous quality assurance. This work aims to assess five methods for quality assurance of SIMT treatment plans in terms of their suitability and sensitivity to delivery errors. Methods: Sun Nuclear ArcCHECK and SRS MapCHECK, GafChromic EBT Radiochromic Film, machine log files, and Varian Portal Dosimetry were all used to measure 15 variations of a single SIMT plan. Variations of the original plan were created with Python. They comprised various degrees of systematic MLC offsets per leaf up to 2 mm, random per‐leaf variations with differing minimum and maximum magnitudes, simulated collimator, and dose miscalibrations (MU scaling). The erroneous plans were re‐imported into Eclipse and plan‐quality degradation was assessed by comparing each plan variation to the original clinical plan in terms of the percentage of clinical goals passing relative to the original plan. Each erroneous plan could be then ranked by the plan‐quality degradation percentage following recalculation in the TPS so that the effects of each variation could be correlated with γ pass rates and detector suitability. Results & conclusions: It was found that 2%/1 mm is a good starting point for the ArcCHECK, Portal Dosimetry, and the SRS MapCHECK methods, respectively, and provides clinically relevant error detection sensitivity. Looser dose criteria of 5%/1 mm or 5%/1.5 mm are suitable for film dosimetry and log‐file‐based methods. The statistical methods explored can be expanded to other areas of patient‐specific QA and detector assessment. [ABSTRACT FROM AUTHOR]

The X-ray Integral Field Unit (X-IFU) is one of the two focal plane detectors of Athena, a large-class high energy astrophysics space mission approved by ESA in the Cosmic Vision 2015–2025 Science Program. The X-IFU consists of a large array of transition edge sensor micro-calorimeters that operate at ~100 mK inside a sophisticated cryostat. To prevent molecular contamination and to minimize photon shot noise on the sensitive X-IFU cryogenic detector array, a set of thermal filters (THFs) operating at different temperatures are needed. Since contamination already occurs below 300 K, the outer and more exposed THF must be kept at a higher temperature. To meet the low energy effective area requirements, the THFs are to be made of a thin polyimide film (45 nm) coated in aluminum (30 nm) and supported by a metallic mesh. Due to the small thickness and the low thermal conductance of the material, the membranes are prone to developing a radial temperature gradient due to radiative coupling with the environment. Considering the fragility of the membrane and the high reflectivity in IR energy domain, temperature measurements are difficult. In this work, a parametric numerical study is performed to retrieve the radial temperature profile of the larger and outer THF of the Athena X-IFU using a Finite Element Model approach. The effects on the radial temperature profile of different design parameters and boundary conditions are considered: (i) the mesh design and material, (ii) the plating material, (iii) the addition of a thick Y-cross applied over the mesh, (iv) an active heating heat flux injected on the center and (v) a Joule heating of the mesh. The outcomes of this study have guided the choice of the baseline strategy for the heating of the Athena X-IFU THFs, fulfilling the stringent thermal specifications of the instrument. [ABSTRACT FROM AUTHOR]

Heterodyne detection based on interband cascade lasers (ICL) has been demonstrated in a wide range of different applications. However, it is still often limited to bulky tabletop systems using individual components such as dual laser setups, beam shaping elements, and discrete detectors. In this work, a versatile integrated ICL platform is investigated for tackling this issue. A RF-optimized, two-section ICL approach is employed, consisting of a short section typically used for efficient modulation of the cavity field and a long gain section. Such a laser is operated in reversed mode, with the entire Fabry–Pérot waveguide utilized as a semiconductor optical amplifier (SOA) and the electrically separated short section as detector. Furthermore, a racetrack cavity is introduced as on-chip single-mode reference generator. The field of the racetrack cavity is coupled into the SOA waveguide via an 800 nm gap. By external injection of a single mode ICL operating at the appropriate wavelength, a heterodyne beating between the on-chip reference and the injected signal can be observed on the integrated detector section of the SOA-detector. [ABSTRACT FROM AUTHOR]

Copyright of Nuclear Safety is the property of Nuclear & Radiation Safety Center 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 Bulletin of the L.N. Gumilyov Eurasian National University. Technical science & Technology series is the property of L.N. Gumilyov Eurasian National University 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.)

AbstractThe specific activity concentrations of naturally occurring radionuclides in soil samples collected from suburban areas of Assosa City was measured using a High purity Germanium (HPGe) detector. The average specific activity concentrations of 238U and 232Th exceed the recommended safe value of 35.0 and 30.0 Bq kg−1, respectively. For 40K, the average activity concentration is below the recommended safe value of 400.0 Bq kg−1. The calculated mean value of the absorbed dose rate is 72.8 ± 3.72 nGy h−1 which exceed the recommended safe value of 59 nGy h−1. The calculated mean annual effective dose equivalent values for indoor and outdoor are 2.11 ± 0.1 mSv y−1 and 0.52 ± 0.02 mSv y−1, respectively. The calculated mean values of the internal hazard index, external hazard index, and gamma index are 0.43 ± 0.013, 0.56 ± 0.01, and 0.5 ± 0.01, respectively, and those values are below the recommended safe value of one. The mean value of excessive lifetime cancer risk is above the threshold value of 0.29 × 10−3. From this study, it is recommended that Assosa soil needs further investigations. [ABSTRACT FROM AUTHOR]

13N ultra-high purity germanium single crystal is the core material for producing ultra-high purity germanium detectors. This article obtains reduced germanium ingots by reduction method, then purifies them by horizontal zone refining method to obtain 12N high-purity germanium polycrystals, and finally grows 13N ultra-high purity germanium single crystals by Czochralski method. The performance of 13N ultra-high purity germanium single crystal was tested and studied through lowtemperature Hall test, dislocation density test, and deep level transient spectroscopy (DLTS) detection. The low-temperature Hall results show that the average mobility of the crystal head cross-section is 4. 515 × 104 cm² ·V-1 ·s-1, the carrier concentration is 1. 176 ×1010 cm-3, and the conductivity is p-type, the dislocation density at the crystal head is 2 256 cm-2. The average mobility of the tail section is 4. 620 ×104 cm² ·V-1 ·s-1, the carrier concentration is 1. 007 ×1010 cm-3, and the conductivity type is p-type, the dislocation density at the tail of the crystal is 2 589 cm-2. The concentration of deep level impurities in the crystal is 1.843 ×109 cm-3. The results indicate that the crystal is 13N ultra-high purity germanium single crystal. [ABSTRACT FROM AUTHOR]

Copyright of e & i Elektrotechnik und Informationstechnik is the property of Springer Nature 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 Fire Safety Science is the property of Fire Safety Science Editorial Office 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.)

Signal-to-noise ratio (SNR) analysis is a crucial component of optical system development for space remote sensing instruments. It serves as a quantitative assessment of the imaging quality and radiometric characteristics of space remote sensing. This paper utilizes the working principles and energy transfer principles of space remote sensing instruments to conduct SNR analysis and model development for commonly used spaceborne imagers, spaceborne imaging spectrometers, micro-optical remote sensing instruments, and point-source spatial targets. Additionally, the paper also examines the impact of the presence and width of slits in different space environments on the SNR of space remote sensing instruments. The calculation results indicate that the analysis of Signal-to-Noise Ratio (SNR) for different space remote sensing instruments requires the establishment of distinct SNR models. The magnitude of SNR primarily depends on crucial factors such as optical system quality, detector performance, and the space environment. Therefore, in the instrument design and data processing processes, it is essential to consider how to maximize SNR and establish more accurate corresponding SNR models to provide high-quality remote sensing data.

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

Metal halide perovskite (MHP) detectors are highly esteemed for their outstanding photoelectric properties and versatility in applications. However, they are unfortunately prone to degradation, which constitutes a significant barrier to their sustained performance. This review meticulously delves into the causes leading to their instability, predominantly attributable to factors such as humidity, temperature, and electric fields and, notably, to various radiation factors such as X-rays, γ-rays, electron beams, and proton beams. Furthermore, it outlines recent advancements in strategies aimed at mitigating these detrimental effects, emphasizing breakthroughs in composition engineering, heterostructure construction, and encapsulation methodologies. At last, this review underscores the needs for future improvements in theoretical studies, material design, and standard testing protocols. In the pursuit of optimizing the chemical stability of MHP detectors, collaborative efforts are in an imperative need. In this way, broad industrial applications of MHP detectors could be achieved. [ABSTRACT FROM AUTHOR]

Many scientific applications from rare-event searches to condensed matter system characterization to high-rate nuclear experiments require time-domain triggering on a raw stream of data, where the triggering is generally threshold-based or randomly acquired. When carrying out detector R &D, there is a need for a general data acquisition (DAQ) system to quickly and efficiently process such data. In the SPLENDOR collaboration, we are developing the Python-based SPLENDAQ package for this exact purpose—it offers two main features for offline analysis of continuous data: a threshold triggering algorithm based on the time-domain optimal filter formalism and an algorithm for randomly choosing nonoverlapping segments for noise measurements. Combined with the commercially available Moku platform, developed by Liquid Instruments, we have a full pipeline of event building off raw data with minimal setup. Here, we review the underlying principles of this detector-agnostic DAQ package and give concrete examples of its utility in various applications. [ABSTRACT FROM AUTHOR]

Among all the nuclei, Thorium-229 has the lowest excited level at approximately 8.3 eV. This level is an isomeric state with a long radiative lifetime. Therefore, 229 Th can be excited to the isomeric state using a vacuum ultraviolet laser and is expected to have applications such as in frequency standards. Our group has been conducting experiments to excite 229 Th to the isomeric state via the second excited state using the high-intensity X-ray beam available at the SPring-8 facility. To detect vacuum ultraviolet photons from the isomeric state of 229 Th, a dedicated apparatus was constructed. We employed 229 Th-doped CaF 2 crystals as the irradiation target. Because these targets emit numerous scintillation photons due to nuclear decay and X-ray beam irradiation, detectors are required to significantly reduce these background events. To achieve this, we adopted dichroic mirrors and a photomultiplier tube for detecting scintillation photons by nuclear decay, in addition to a solar-blind photomultiplier tube for detecting decay photons from the isomeric state of 229 Th. In this proceedings paper, we describe the experimental apparatus used in the beamtime in 2023. [ABSTRACT FROM AUTHOR]

The article presents assemblage of Seleucid and Greco-Bactrian coins found by the Czech-Uzbek archaeological expedition in the frame of a sampling metal detector survey in the upper reaches of Sherabad Darya, from the sites of the Darband Wall, Daganajam, Kurganzol and Iskandar Tepa in 2018. Sixteen specimens, of both silver and copper alloys, which were determined including a very rare Seleukos I (?) coin are assessed not only from the numismatic and historical point of view, but also analysed in terms of elemental composition. [ABSTRACT FROM AUTHOR]

Copyright of Safety & Security Sciences Review / Biztonságtudományi Szemle is the property of Obuda University 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.)

Single-photon detector is a device that can detect fragile light signals such as photons. Noise is one of the major problems of Single-Photon Avalanche Diode (SPAD) in quantum communication and other applications. The two main noises in SPAD are afterpulse and dark count rate. Afterpulse is one of the most critical challenges of SPAD type InGaAs at 1550 nm wavelength. Several solutions have been presented to reduce noise. One of the most important methods presented is based on pulse gate. Pulse gate is effective in noise reduction by limiting SPAD operation time. Self-differentiating and up-conversion methods are also used in telecommunication wavelength SPADs to reduce noise, which have high implementation costs due to their complex structure. In this paper, we present a novel method for SPAD noise reduction. In this method, the time of SPAD output pulses is recorded and checked. The processor detects photon pulses and noise with a new algorithm. Noise pulses are removed, and photon pulses remain. This method is suitable for some Quantum Key Distribution (QKD) protocols that are simultaneous sender and receiver. It cannot be used in LiDAR and other similar asynchronous applications. The noise reduction method presented in this paper can be used for all types of single photon detectors and at different wavelengths. Also, this method can be used simultaneously with other noise reduction methods and it greatly reduces the amount of noise.

Contamination of food and water with radioactive substances is a serious health problem. There are several methods to detect and measure radioactive materials, some of which have been developed in recent years. This paper aims to discuss the methods of detecting and measuring radioactive substances in food and water. The principles and the advantages and disadvantages of each method have been discussed. The results showed that some of these methods, such as spectrometry γ-ray high purity germanium, portable radon gas surveyor SILENA, RAD7, and inductively coupled plasma mass spectrometry, have a higher sensitivity for detection and measurement. Also, the spectrometry γ-ray high purity germanium method has attracted more attention than other methods because it can measure a wide range of radionuclides with high resolution.