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Radiation Portal Monitors (RPM) manufactured by the National Research and Innovation Agency of Indonesia made from NaI(TI) Sodium Iodine crystal scintillators gamma-ray detectors. Due to the certification process, this RPM was tested followed by SNI IEC 62244:2016 in 2019. seven procedures were unable to do because of the limitation of the facility in Indonesia, six procedures meet the requirement and two procedures didn't meet the requirements of the standards. In 2021, the National Standardization Agency of Indonesia (BRIN) released a new version of the standards, SNI IEC 62244:2019. Due to ensure that RPM meets the new standards, a throughout review should be done for every requirement in the new standards. The result of the review shows that there are significant differences in some clauses and test procedures. For ensuring that RPM meets the new standards, we can conclude that all the procedures required in the new standard need to be tested. [ABSTRACT FROM AUTHOR]

We have studied the anisotropic magnetic properties of Ln2Re3Si5 (Ln=Ce, Pr, Ho) single crystals by means of isothermal magnetization (M), magnetic susceptibility (χ), and heat capacity (CP). The Ce2Re3Si5 did not show any magnetic transition down to 2 K, and exhibits a low value of magnetic susceptibility. This suggests that Ce ions are in the intermediate valence state. Pr2Re3Si5 was found to exhibit antiferromagnetic (AFM) ordering at TN= 9 K in, a spin flip-like metamagnetic transition was observed at 3.5 T for H || [001] in the M vs. H plot. The anisotropic magnetic properties of Pr2Re3Si5 have been explained by the crystalline electric field (CEF) effect based on a point charge model. From the CEF analysis, we find that the 9-fold degenerate (2J+1) ground state splits into 9 levels with an overall splitting of 1179 K. The Ho2Re3Si5, on the other hand, shows two AFM transitions at TN1= 3.8 K and TN2= 4.2 K. Interestingly, three field-induced metamagnetic transitions near 0.45 T, 1 T, and 1.5 T at 1.8 K in Ho2Re3Si5 have been observed. These compounds exhibit significant anisotropy in magnetic properties along two main crystallographic directions viz., [100] and [001]. [ABSTRACT FROM AUTHOR]

In this report, we have developed an intrinsic 3-hydroxyflavone (3HF) scintillator, less susceptible to radiation damages, by thermal polymerization reaction at 120°C. Radioluminescence, decay time and the light yield are measured. The changes occurred in the light yield are evaluated for the 60Co irradiations with total absorbed radiation dose of 4.8 Mrad under normal conditions. [ABSTRACT FROM AUTHOR]

Indonesia is a ring of fire country that often occurs earthquakes. Research on earthquake-resistant houses is very challenging to do, so it needs to be supported by a monitoring system for house building materials. Muon tomography uses an alternative technology that utilizes the 24/7 presence of cosmic muon rays that can be applied to create an image of a building in Indonesia. Muon tomography has the advantage that it does not require radioactive material and has a much deeper penetrating power into the material, up to a scale of hundreds of meters. The objective of this study was to review and design essential elements of a muon detector to detect building quality, especially cracks in houses. Comparative investigations of various muon detection methods concluded that the best method of muon detection in Indonesia is with a scintillation detector, particularly by the plastic material, due to its convenience and resolution. Simulation of visible fluorescent light from a plastic scintillator has used a laser beam-controlled quantity by a microcontroller. The muon detector simulation through a photodiode sensor implemented an optical power meter (OPM) to validate its strength. Experimental results show that the distance between sensors was an important factor in designing a precision muon detector. The location of the muon detector should be laid on the foundation, beams, and column of the earthquake-resistant house design. [ABSTRACT FROM AUTHOR]

High-resolution X-ray microtomography at 200 keV region was developed at bending magnet beamline BL28B2 in SPring-8. In this study, synchrotron radiation based high-energy white X-rays with the peak energy of around 200 keV was employed. To achieve high-resolution X-ray microtomography at 200 keV region, contribution of the effective thickness of the scintillator in a visible-light conversion type X-ray imaging detector was experimentally evaluated by changing the thickness of the scintillator and the aperture size of a lens system used as visible-light optics. The thin scintillator with smaller aperture size provided a better spatial resolution. Even in the thick scintillator, the spatial resolution could be improved by increasing the effective depth of focus of the lens system on the scintillator with smaller aperture size. As a result, t-resolution X-ray microtomography, a multi-scale observation of a D-size battery was conducted. The local fine structure as well as the entire shape of the battery could be clearly observed. [ABSTRACT FROM AUTHOR]

High-resolution X-ray microtomography at 200 keV region was developed at bending magnet beamline BL28B2 in SPring-8. In this study, synchrotron radiation based high-energy white X-rays with the peak energy of around 200 keV was employed. To achieve high-resolution X-ray microtomography at 200 keV region, contribution of the effective thickness of the scintillator in a visible-light conversion type X-ray imaging detector was experimentally evaluated by changing the thickness of the scintillator and the aperture size of a lens system used as visible-light optics. The thin scintillator with smaller aperture size provided a better spatial resolution. Even in the thick scintillator, the spatial resolution could be improved by increasing the effective depth of focus of the lens system on the scintillator with smaller aperture size. As a result, t-resolution X-ray microtomography, a multi-scale observation of a D-size battery was conducted. The local fine structure as well as the entire shape of the battery could be clearly observed. [ABSTRACT FROM AUTHOR]

The most discussed topic in direct searches for dark matter is arguably the verification of the DAMA claim. In fact, the observed annual modulation of the signal rate in an array of NaI(Tl) detectors can be interpreted as the awaited signature of dark matter interactions. Several experimental groups are currently engaged in the attempt to verify such a game-changing claim with the same target material. However, all present-day designs are based on a light readout via Photomultiplier Tubes, whose high noise makes it challenging to achieve a low background in the 1–6 keV energy region of the signal. Even harder would be to break below 1 keV energy threshold, where a large fraction of the signal potentially awaits to be uncovered. ASTAROTH is an R&D project to overcome these limitations by using Silicon Photomultiplier (SiPM) matrices to collect scintillation light from NaI(Tl). The all-active design based on cubic crystals is operating in the 87–150 K temperature range where SiPM noise can be even 100 lower than that of PMTs. The cryostat was developed following an innovative design and is based on a copper chamber immersed in a liquid-argon bath that can be instrumented as a veto detector. We have characterized separately the crystal and the SiPM response at low temperature, and we have proceeded to the first operation of a NaI(Tl) crystal read by SiPMs in cryogeny. [ABSTRACT FROM AUTHOR]

The 20 kton liquid scintillator detector of the Jiangmen Neutrino Underground Observatory (JUNO), which is currently under construction in Southern China, has a vast potential for new insights into various fields of (astro-)particle physics. Stringent limits on the liquid scintillator radiopurity are required for several physics goals of JUNO. For both 232Th and 238U, a radiopurity of 10−15 g/g is required for reactor antineutrino measurements, 10−16 g/g for solar neutrino measurements. An independent detector, the Online Scintillator Internal Radioactivity Investigation System (OSIRIS), will be used to ensure these limits are kept. This report will present OSIRIS and its sensitivity to 232Th and 238U in detail. OSIRIS allows an online radiopurity evaluation of the scintillator during the months-long filling of JUNO. The design of OSIRIS is optimized for tagging fast 214Bi-214Po and 212Bi-212Po coincidence decays in the decay chains of 238U and 232Th, respectively. The coincident decay signatures and their rates offer a potent background rejection as well as a direct translation into 238U-/232Th-abundances in the scintillator. OSIRIS will also be able to measure the levels of 14C in the scintillator, down to a 14C/12C ratio of 10−17 at 90% confidence level. Furthermore, the level of 210Po and a possible contamination by 85Kr can be determined. To achieve its goals, OSIRIS features a water-submerged 20 ton liquid scintillator target monitored by 76 intelligent photomultiplier tubes (iPMTs). The novel design of the iPMTs allows a triggerless readout scheme with high signal quality. A single computer is sufficient to process the data stream into events for further analysis. The timing and charge calibration of the iPMTs will be performed with Laser-and LED-based systems. The energy and vertex reconstructions will utilise height-adjustable radioactive sources within the liquid scintillator. [ABSTRACT FROM AUTHOR]

In the present study, we report the synthesis of ZnWO4 nanoparticles by hydrothermal method. The crystallographic phase purity and homogeneity pattern of synthesized ZnWO4 nanoparticles are characterized by X-ray powder diffraction (XRD). The crystallite size along with the lattice strain is calculated using W-H plot and compared with that from Debye-Scherer formula. UV/VIS/NIR absorption spectroscopy is carried out and optical constants are evaluated. The micro morphology and composition of ZnWO4 are studied with FE-SEM and Energy dispersive X-ray spectroscopy (EDAX). [ABSTRACT FROM AUTHOR]

A novel type of scintillator detector based on microfluidic technology that is used to determine the input function in real time has been proposed. Manipulation of the microfluidic geometric designs were done to determine the optimum design that can produce meaningful photon statistics. GEANT4 simulation toolkit was used to assess the key characteristics of the microfluidic scintillator detector, particularly in optimising the photon detection. It allows users to modify geometry description, physics processes, managing hit events and detector response. Modifications were done to the scintillator thickness as well as the dimensions of the microfluidic channel lengths to examines their relationships with the number of photons detected on the SIPM. The maximum depth of the positron particle in the plastic scintillator is approximately at 2.4 mm for 18F. Reducing the thickness of plastic scintillator to 2 mm may reduce photon collection by approximately 10% for 18F. By changing the microfluidic channel length from short to longer (constant volume), there is an increase of 9% photon detection. [ABSTRACT FROM AUTHOR]

This work is based on the design introduced by the cosmic watch project from the Massachusetts Institute of Technology has been constructed and compromised to be used for radiation detection and dosimetry applications. This single detector is a potential replacement for neutron and gamma-ray detectors in radiation portal monitors (RPM) systems. Non-linear dose-response of this detector while exposure to gamma dose rate in the µGy/hr range is obtained while linear count rate is obtained for exposure to the neutron flux. Neutron flux distribution around the Am–Be neutron source, neutron security gating, and gamma dosimetry are three successful applications checked in this study. The obtained results recommend using this plastic scintillator as a potential single-detector replacement for both neutron and gamma-ray detectors in radiation portal monitors (RPM) systems. [ABSTRACT FROM AUTHOR]

Compton camera is a radiation detector that uses the kinematics of Compton scattering to estimate the direction of the gamma-ray incident. Compton camera has been used in many applications such as astronomy, medical, nuclear industry, and security. High time resolution in a Compton camera is essential to distinguish the incoming event in the detector. In this work, we developed a Compton camera using a fast decay scintillator and a high time resolution front end circuit to get a high-performance detector. The detector used an 8×8 multi-pixel photon counter (MPPC) array, which individually couple with a 2.5×2.5×5 mm3 GFAG (Gadolinium Fine Aluminum Gallate) scintillator. For processing the analog signal from the MPPC scintillators, the 64 channel ASIC (Application-Specific Integrated Circuit) is used. Each channel in the ASIC circuit consists of a pre-amplifier, shaper, monostable multivibrator, and slew-rate time over threshold. The ASIC will provide the digital output signal that contains the timing and energy information. The high-time resolution data acquisition circuit (PETnet) based on FPGA is used to acquire energy and time data from ASIC. [ABSTRACT FROM AUTHOR]

Thallium doped sodium iodide scintillation detector is the most widely used scintillation detector in gamma spectrometry. Unfortunately, sodium iodide reaches insufficient energy resolution for many applications. This fact has led manufacturers to develop scintillators with better energy resolution such as LaBr3:Ce and CeBr3. The energy resolution of LaBr3:Ce is about 3 times better and the resolution of CeBr3 is about 2 times better than the resolution of NaI:Tl. On the other hand, the production costs is still a disadvantage of these newer scintillators. The paper deals with energy resolution functions comparison of the 1.5 inch NaI:Tl, CsI:Tl, LaBr3:Ce, and CeBr3 scintillation detectors. The measurements and analysis to find the best fitting functions for energy resolution were performed. [ABSTRACT FROM AUTHOR]

The optical spectra of BaBrI crystals activated by divalent samarium were studied. The samples exhibit bright luminescence in the red region of spectra due to 4f6–4f6 and 4f55d1–4f6 transitions of Sm2+ ions. Luminescence exhibits strong temperature dependence in the range 7–300 K. At low temperatures, luminescence associated with parity-forbidden 4f6–46f transitions from 5D0 and 5D1 states is observed. Coloring of the crystals after irradiation by ultraviolet light and long afterglow luminescence of BaBrI:Sm2+ were detected. [ABSTRACT FROM AUTHOR]

A precision hybrid magnetic three-arm «SCAN-3» spectrometer is being developed at the Joint Institute for Nuclear Research. The spectrometer is designed to detect charged particles (π±, K±, p) and neutrons produced in the target by collisions of the NUCLOTRON high-interactive beam particles with target nuclei. One of the tasks of the spectrometer is to detect neutrons from the decay of the η-meson nucleus via nπ- and pn- channels. To complete this task, two arms of the spectrometer will be created that consist of six multilayer neutron detectors based on scintillation blocks. The characteristics of a neutron detector that consists of five scintillation blocks are considered. The detector was studied using the cosmic rays and the neutron beam produced by the stripping reaction of the NUCLOTRON extracted deuteron beam on a fixed target. [ABSTRACT FROM AUTHOR]

The Baryonic Matter at Nuclotron (BM@N) is the first experiment with a fixed target at the Nuclotron-based Ion Collider fAcility (NICA) in Dubna (Russia). Along with baryonic matter study, the BM@N physics program includes the study of Short-Range Correlations (SRC) in nuclei. The SRC measurement was carried out in 2018. We used 12C beam with the momentum of 48 GeV/c and a liquid hydrogen target. The quasi-free scattering of 12C on protons was recorded with the BM@N spectrometer, which was slightly modified for the SRC experiment. Particularly, the target proton and knocked out proton under the condition of scattering at 90 degrees in the center-of-mass coordinate system were recorded in the arm spectrometer using time-of-flight and coordinate detectors. After interaction, the residual nucleus continued moving along the beam and passed through the scintillator and coordinate detectors as well as the analyzing magnet. This contribution describes the track reconstruction in Multiwire Proportional Chambers (MWPC) and Silicon Detector systems (Si), as well as a method of obtaining combined tracks after the target using the information from MWPC and Si. This is a basis for the identification of nuclear fragments described in the first physics analysis, which was submitted for publication. [ABSTRACT FROM AUTHOR]

Scintillator crystals are widely used as ionizing radiation detectors in nuclear medicine imaging equipment. In many detectors, arrays of small scintillator elements (pixels), optically isolated from each other by a reflective material, are used to provide information on the interaction position of photons in the crystal. The attainable spatial resolution is related to the pixel size. The technique of subsurface laser engraving has been proposed as a low-cost alternative to scintillation crystals arrays to pixelate monolithic crystals. In this work, the first results of the implementation of the laser engraving technique to pixelate cerium doped lutetium yttrium oxyorthosilicate (LYSO:Ce) scintillation crystals in the new Laser Engraving Laboratory at the UNAM Institute of Physics are presented. We characterized the shape and size of the induced microfractures with a Nd:YAG pulsed laser in LYSO crystal, and with this information, we optimized the engraving parameters to produce semi-transparent barriers that optically isolate one pixel from another, thus producing a 6×6 pixelated crystal array with pixel pitch of 1.67 mm. [ABSTRACT FROM AUTHOR]

The parallax error introduced by incorrectly assigning the lines-of-response defined by the annihilation photon pairs, limits the attainable spatial resolution in positron emission imaging. Knowledge of the exact position of interaction (x, y, z) inside the scintillation crystal, including the depth of interaction z of the 511 keV photons, reduces this error. In this work, the depth of interaction (DOI) was determined in two different scintillator materials: EJ-232 plastic and LYSO scintillation crystals. These were coupled to an 8×8 silicon photomultiplier (SiPM) array. An analysis of the light distributions produced inside the crystals enabled the determination of the DOI position, allowing the correction for parallax errors. This method is expected to be used in a Positron Emission Mammography (PEM) prototype under development. [ABSTRACT FROM AUTHOR]

Solid-state scintillation materials reach a pick of their popularity and one of such attractive materials is the new Gd3Al2Ga3O12:Ce single crystal with unique and promising scintillation properties. The fundamental optical properties of this crystal and the effect of the composition deviations on them are studied poorly. This investigation is focused on the estimation of the influence of the Al to Ga partial substitution in the Gd3Al5-xGaxO12 cationic sublattice on the transmission spectra and refractive indices. In this work transmission spectral dependences and the refractive indices dispersion dependences were obtained by spectrophotometric methods using certified methods on calibrated equipment. The effect of the cationic substation on the transmission spectra is weak, slight decrease in intensity of Al:Ga ration 3:2 samples was observed in the wavelength region 200-350 nm. In the studied wavelength range 200-700 nm refractive index values of the crystals with an Al to Ga ratio 3:2 are lower than values of the crystals with a 2:3 ratio. [ABSTRACT FROM AUTHOR]

Scintillators are vital to X-ray and high-energy particle detection. Specifically, thin scintillators like phosphor screens are a prime component in detectors of soft-X-rays, electron cameras, and light intensifiers. All such applications are limited by the scintillator's response time and efficiency. Moreover, there exists an intrinsic trade-off due to the isotropic nature of spontaneous emission at the heart of the scintillation process: On the one hand, the thicker scintillator layers that are required for high efficiency of detecting the radiation also cause a dramatic image deterioration and blurring. On the other hand, thinner scintillator layers can provide higher image resolution yet that comes at the price of lower efficiency of detecting the radiation and thus a lower signal-to-noise ratio. In this paper, we introduce a novel design of thin scintillators that can achieve simultaneously high-efficiency and high-resolution, by proposing a new concept of scintillating nanophotonic structures. We exploit the photonic local-density-of-states (LDOS) in scintillating nanostructures made from scintillator layers, stacked between other dielectric layers. We use a specialized optimization algorithm to determine the thicknesses of each layer in the multi-layer structure and to maximize the emission rate, directionality, and efficiency. As an example, we examine an overall structure width of only 2.5 μm, and find that the emission rate can be enhanced by a factor of 5.2 (when combining a scintillator with a refractive index of 1.59 with a dielectric material with a refractive index of 2.1). We show how the optimized structure can enhance the emission in the desired bandwidth to match with any scintillator material, thus improving the detector resolution and efficiency simultaneously in several radiation detection applications. [ABSTRACT FROM AUTHOR]

The tungsten-containing composite based on PMMA was obtained by method of radiation-initiated polymerization. The composite was investigated by several methods. The XANES/EXAFS method showed that tungsten in the composite is in the carbonyl form. The study of the luminescent properties showed that the tungsten-containing composite has the properties of an ultrafast X-ray scintillator in the red region of UV-spectrum. [ABSTRACT FROM AUTHOR]

This work considers the optical properties and structure of thin films of titanium dioxide formed by glancing angle deposition to improve the light yield of scintillation materials. The experimentally obtained value of the refractive index was about 1.2, which is almost two times less than the refractive index of crystalline titanium dioxide. This allows you to use this method to modify the optical properties of the surfaces of scintillators with a large refractive index. [ABSTRACT FROM AUTHOR]

Fluid flow in most reservoirs is anisotropic. The reservoir structures are usually layered and frequently contain significant heterogeneities leading to directional variations in the extent of flow. Hence, the effective fluid movement can be difficult to predict. Hence, there is an immediate need to investigate and understand the behavior of reservoir during water-flooding specifically the fluid flow and transport behavior using radiotracer. Thus, a lab scale of sand pack has been set up to investigate the compatibility of radiotracer technique in assisting the behavior of sandstone reservoir in Malaysia. A full packed of sandstone with grain size of 800-900µm has been set up for this study. The sand pack is then connected to water reservoir to introduce water-flooding activity. The radiotracer used is Br-82 with activity of approximately 1mCi. The irradiation of NH4Br is carried out at Nuclear Malaysia research reactor using Pneumatic Transfer System (PTS) facility for 3 minutes. Five (5) NaI scintillation detectors are also located at various places outside the reservoir to look at the anisotropic effect, the property of being directionally dependent, which implies different properties in different directions of Br-82. The optimization of Residence Time Distribution (RTD) model from radiotracer experiments will present the characterization of the porous media. This is important knowledge in order to optimize the oil recovery. The present study shows that, the porous media represents perfect mixers in parallel model. The selection of this model is due to the minimum value of root mean square RMS which is 0.217e−8. The optimized parameters of the respective model are τ1 = 848, τ2 = 145, J1 = 3.14, J2 = 3.18 and Q1/Q2 = 0.952. The objective of this study is to leverage the potential of radio-tracing technique, a method that is scarcely utilized in water-flooding studies. It is able to analyze the reservoir behavior and the information obtained can be set and optimize a development plan for increasing the oil recovery efficiency for EOR application. [ABSTRACT FROM AUTHOR]

Inorganic nanophosphor materials have captivated the worldwide attention into the field of solid-state lighting emission displays, plasma display panels, light-emitting diodes, IR quantum counters, scintillation, etc. Nanotechnology is the foremost superior in the development of phosphors with definite size and shape. Alkali and alkaline earth phosphates are promising candidates for the inorganic phosphor materials. Manufacturing of nano-inorganic materials gained much interest due to their advance lighting applications. In this work, novel Co2+ doped Calcium Cadmium Phosphate hydrate nanophosphor (CaCdPH: Co2+) was synthesized by a traditional solid-state reaction technique. The synthesized sample was characterized by Powder XRD, SEM equipped with EDX and FTIR techniques. The hexagonal phase of the prepared CaCdPH: Co2+sample was confirmed by x-ray diffraction results, and the average crystallite size was evaluated. FTIR demonstrated the formation of vibrational modes ascribed to phosphate molecules and other hydroxyl groups. The morphologies of the CaCdPH: Co2+ nanophosphor was investigated by scanning electron microscopy. [ABSTRACT FROM AUTHOR]

Silicon photomultipliers (SiPMs) are gaining popularity over conventional photomultiplier tubes (PMTs) in various radiation detection applications. For this application, it is necessary to optimize the scintillator material and its geometry. In order to develop a compact, low power gamma spectrometry system based on a scintillator coupled SiPM detector, energy deposition in Gd3Ga3Al2O12(Ce) (abbreviated as GGAG(Ce)), NaI(Tl) and CsI(Tl) scintillators of different dimensionswas calculated using Monte Carlo simulation code FLUKA for different gamma energies from 60 keV to 2614 keV. It is observed that energy deposition is highest in GGAG(Ce) followed byCsI(Tl) and NaI(Tl) respectively. By increasing thepath length of the scintillator, energy deposition is seen to increase for energies 662 keV, 1250 keV and 2614 keV. However, for 60 keV, the increase in longitudinal dimension above 3 mm does not affect the energy deposition. Based on the simulation data,GGAG(Ce) scintillator with 3×3×24 mm3 geometry was chosen for making a scintillator coupledSiPM detector. [ABSTRACT FROM AUTHOR]

We developed an experimental setup for the measurement of soft X-ray excited optical luminescence at the reflectivity beamline (BL-4), Indus-1 synchrotron radiation source. The soft X-ray excited visible luminescence signal from sample was collected using a lens assembly and focused on to a ∼200 µm optical fiber coupled to thermoelectric (TE) cooled spectrometer. The photo luminescence signal from the samples mounted inside a vacuum chamber was brought to the luminescence collection unit mounted in the air through a glass view port. The toroidal grating monochromator of the beamline provided the soft x-rays for excitations in the range of ∼10 eV to 300 eV (100 nm – 4 nm) and the resultant optical luminescence was recorded in the range of ∼350 nm to 900 nm. The developed setup was demonstrated by the recording the visible emission from standard scintillator materials (Cr:Al2O3, Ce:YAG, etc.) and β-Ga2O3 nanostructure. [ABSTRACT FROM AUTHOR]

Silicon photodiodes coupled to scintillators are widely used for X-ray imaging applications involving radiography and tomography for security or medical applications. X-ray baggage inspection systems (XBIS) are used for detection of threat materials using dual energy radiography of objects. A basic understanding of these systems in terms of generation of scintillation photons, energy deposition in scintillators and charge generation in photodiodes is essential for the design of the systems and for optimizing the detector parameters to achieve desired imaging performance. In the present work, Monte Carlo simulations were carried out to analyze the performance of detectors starting from theoretical generation of X-ray spectrum. Using this spectrum detector performance for dual energy material discrimination was studied. X-ray images of objects for evaluating penetration capability were also obtained. The R-values were calculated for different materials for mono-energetic X-ray photons which were observed to be constant with the thickness of the material. However, these values were observed to be decreasing with the increase in the thickness of the material when actual 140 keV X-ray spectrum was used for the simulation. [ABSTRACT FROM AUTHOR]

Gd1.5Y1.5Ga3Al2O12(GYGAG:Ce) a multi component garnet scintillator was synthesizedby solid state and chemical technique. Both the technique found to yield single phase material with luminescence at 540 nm. The powder when casted in a polymer matrix was able to detect X-ray spot. [ABSTRACT FROM AUTHOR]

We report current status of the LEPS2 solenoid spectrometer for photoproduction experiments at SPring-8. A large solenoid LEPS2 spectrometer consists of a time projection chamber (TPC), drift chambers, resistive plate chambers and Pb/scintillator sampling calorimeters for photoproduction of hadrons in the energy range from 1.4 to 2.9 GeV. We have developed a new, network-distributed data acquisition system based on DAQ-middleware framework. The DAQ middleware components include gatherers collecting data from detector sub-systems, mergers integrating data from gatherers, and an event builder in the data acquisition software. Over ten thousand pad signals from the TPC are digitized with 40 MS 12-bit flash ADCs and then sent to a TPC gatherer through Space-Wire protocol. During the beam commissioning, Compton-backscattered photon beam was incident on a CH2 target in the energy region from 1.4 GeV to 2.4 GeV. We report on the performance test results of the new DAQ system with beam commissioning of the LEPS2 spectrometer as well. [ABSTRACT FROM AUTHOR]

Lutetium-yttrium oxyorthosilicate (LYSO) crystal scintillators were originally developed for medical applications. Owing to their high density, small Molière radius, fast response, and high radiation hardness, LYSO crystals have also suitable for future homogeneous electromagnetic calorimeters. Due to these features, LYSO is considered to be used for the electromagnetic calorimeter part of the Turkish Accelerator Center Particle Factory (TAC-PF) detector. In this research, by employing the GEANT4 toolkit program, we simulated a set of crystal, and their energy resolutions were obtained for different lengths at the energy range of 50 MeV - 2 GeV. Depending on the crystal length, contributions to the constant term of the energy resolution were investigated. [ABSTRACT FROM AUTHOR]

The luminescent characteristics of the LiSrPO4, Sr9Sc(PO4)7, K3Lu(PO4)2 and K3LuSi2O7 microcrystalline powders doped with Pr3+ ions, a promising optical materials for scintillation applications, were investigated using various experimental techniques. The comparative analysis of the luminescent properties of these materials is presented. [ABSTRACT FROM AUTHOR]

Final results of studies of 116Cd 2β decay with CdWO4 crystal scintillators, enriched in 116Cd to 82%, are presented. After few years (2011 – 2017) of measurements with radiopure 116CdWO4 scintillators (mass of 1.162 kg) at the Gran Sasso underground laboratory (Italy), the half-life of 116Cd relatively to 2ν2β decay to the ground state of 116Sn was measured with the highest up-to-date accuracy as T1/2=(2.63−0.12+0.11)×1019 yr. A new limit on 0ν2β decay of 116Cd was set as T1/2≥2.2×1023 yr at 90% C.L., which is the most stringent to-date restriction for this isotope. Limits for 0ν2β decay with majoron(s) emission, Lorentz-violating 2ν2β decay and 2β transitions to excited states of 116Sn were set at the level of T1/2≥1020−1022 yr. [ABSTRACT FROM AUTHOR]

We investigated the discrimination of alpha particles based on the analysis of scintillation light collected by a silicon photomultiplier (SiPM). Particle discrimination with a photomultiplier tube was used as a reference to evaluate the efficiency. We compared standard pulse shape discrimination based on the integral of the SiPM signal to an approach based on Time-Over-Threshold, achieving comparable performances. [ABSTRACT FROM AUTHOR]

This paper is devoted to a plastic scintillator detector calibration method. We calibrated the large volume polystyrene gamma detector SPD200.200.100 by NUVIA Group. The essential issue of the plastic scintillator is that Compton scattering is the dominant effect of photon interaction within the detector and it is no apparent full energy absorption peak in a spectrum. Our approach is based on MCNP code simulation where the detector was modeled. Then measured and calculated spectra are compared to determine the Gaussian energy broadening effect. Finally, the measured spectra can be calibrated using Compton maximum and Compton edge energy. The results of this study show that measured and calculated spectra are in good agreement. [ABSTRACT FROM AUTHOR]

Neutrinos are the ghosts of modern physics. They are the only particles currently observed that might be their own antiparticles: “Majorana” particles. The nuclear process of double beta decay holds the key to this question. Double beta decay with two neutrinos is the longest-lived decay process ever observed, with a lifetime much longer than the universe; neutrinoless double beta decay has not yet been observed. Observing it would confirm that neutrinos are Majorana particles. The Cryogenic Underground Observatory for Rare Events (CUORE) experiment is designed to search for neutrinoless double beta decay in tellurium. It began taking data this year, using 742 kg of tellurium in a new helium dilution cryostat in the Laboratori Nazionali del Gran Sasso in central Italy. The CUORE cryostat, when cold, is the coldest cubic meter in the known universe. We are also preparing for a next-generation CUORE-style experiment, using different crystals in the same cryostat. We are currently investigating the properties of several crystals that are known to double beta decay and could potentially add scintillation light to the bolometric signal currently used in CUORE. [ABSTRACT FROM AUTHOR]

The PADME experiment, at the Laboratori Nazionali di Frascati (LNF) of INFN will perform a search for the production of a low mass gauge boson A′ of a new U(1) symmetry, exploiting a novel positron-on-target-annihilation technique, e+ + e− → γ + A′. The DAΦNE linac will provide 550 MeV positrons directed towards a thin diamond target. The events reconstruction will employ a measurement of the energy and the direction of the recoil photon by a segmented crystal calorimeter, thus allowing the reconstruction of the A′ mass as the missing mass in the final state. A fine-grained plastic scintillator veto composed of three stations in vacuum will suppress the background due to bremsstrahlung emission and a fast Cerenkov detector will help with the multiphoton events rejection. PADME expects to reach sensitivity on the relative coupling strength (ϵ² parameter) down to 10−6, in the mass region 1 MeV < MA′ < 22.5 MeV, for one year of data taking with a 550 MeV beam. [ABSTRACT FROM AUTHOR]

The PADME experiment, starting data taking this year at Laboratori Nazionali di Frascati, INFN, Italy will search for the e+e → γA′ process in a positron-on-target experiment, assuming a decay of the A′ into invisible particles of the hidden sector. 550 MeV positron beam from the DAΦNE Beam-Test Facility will impinge on a thin diamond target and the recoil photon will be registered by a segmented crystal calorimeter, allowing to reconstruct the missing mass of the event. The suppression of the background due to bremsstrahlung emission from the beam positrons requires high efficient charged particle detectors with optimized geometry and sub ns time resolution. A fine-grained plastic scintillator veto composed of three stations in vacuum is being assembled and will be operational in PADME. Two stations are placed inside a dipole magnet with 0.6 T magnetic field and will also provide momentum measurement at the 5 percent level. The light is taken by WLS fibers to a custom developed SiPM readout system which allows to achieve time resolution of the order of 500 ps. The design of the charged particle vetoes and their initial performance is presented. [ABSTRACT FROM AUTHOR]

BaBrI crystals containing 0.01 to 8 mol. % of Eu2+ activator have been obtained. The photo- and X-ray luminescence spectra correspond to Eu2+ 5d – 4f characteristic transitions with a maximum at about 3 eV. The scintillation decay time is 400-500 ns (fast component) and 3700–5500 ns (slow component). It has been established that the decay time in BaBrI crystals depends on the activator concentration. In the absorption spectra of BaBrI: Eu2+ crystals, a double peak is observed associated with 4f7 – 4f65d¹ transitions in Eu2+. On the edge of optical absorption, the band gap of 5.2 eV was estimated. We assume the resonant mechanism of energy transfer to the luminescence centers. [ABSTRACT FROM AUTHOR]

Material research of structural steels used in extreme conditions is important for the safe and reliable operation of individual components of nuclear installations. One of the effective methods of examining their microstructure is positron annihilation lifetime spectroscopy (PALS). For the needs of PALS, new types of detectors are currently being used compared to conventional photomultipliers. These types of detectors, however, are not sensitive to fast ultraviolent component of emission spectrum of the most commonly used scintillation material in this area - barium fluoride. This paper analyses the effect of the usage of LYSO and plastic scintillators on the properties of the spectrometric apparatus. These scintillation materials were linked to the SiPM detectors Sensl MicroFJ-SMA-30035 and Ketek PE6650-EB-AX as well as to the conventional Photonis XP2020Q photomultiplier. [ABSTRACT FROM AUTHOR]

In-vivo dosimetry for brachytherapy has been investigated since decades with a number of different detectors and measurement technologies. X-ray films, semiconductor detectors, thermo-luminescent dosimeters and ionization chambers are the systems most currently used. However, ionization chambers do not allow point-like dose measurements near the tumor, semiconductor detectors are not water equivalent and are very sensitive to temperature changes, and thermoluminescent dosimeters do not allow real-time measurements. For these reasons, during the last two decades, there has been an increased interest for scintillation dosimetry using scintillating fibers, due to their most favorable characteristics and dosimetric properties, as water equivalence, response linearity with increasing dose rates, independence from temperature and small size. In the present work, we present experimental studies of key characteristics of the components of a scintillation dosimeter: the light collection in different types of scintillating fibers and the gain as a function of temperature of a silicon photomultiplier (SiPM), for the design and construction of an in-vivo scintillation dosimeter prototype for brachytherapy. [ABSTRACT FROM AUTHOR]

The study of dynamic compression of materials requires high precision spatial and temporal resolution to infer the material state at any given time. In ultra-fast imaging experiments such as those performed at the Dynamic Compression Sector at the Advanced Photon Source, the current CCD frame rate is less than the X-ray pulse rate necessitating that 4 CCDs be used to image a single scintillator screen to obtain the same projection of transmitted or diffracted beam at time intervals synchronized with the X-ray beam. The use of multiple-camera setups is often employed for a variety of reasons including enhancing the temporal resolution through interleaving frames or increasing the number of viewpoints, for example. Physical corrections are made to have each CCD approximately viewing the same field of view, however we present corrections that can be made after the data collection to further refine and be able to compare movements and changes in the sample between independent CCDs. These software corrections enable higher precision and higher fidelity comparison of position changes due to sample deformation. We present a method to correct images (or frames) as a demonstration toward high fidelity displacement measurements in these types of ultra-fast multi-camera setup experiments. [ABSTRACT FROM AUTHOR]

The samarium doped MgZnO2 phosphor was synthesized by the low-cost combustion method. The powder X-ray diffraction (XRD) analysis confirmed the crystallinity and phase purity of the phosphor. The lattice parameters were determined by indexing the diffraction peaks. The photoluminescence (PL) study revealed that the phosphor exhibited a broad excitation band in the UV region ranging between 200 to 350 nm. The 601 nm emission was ascribed to 4G5/2 to 6H7/2 transitions of the Sm3+ ion. The optical bandgap of MgZnO2:Sm3+ was obtained to be 3.56 eV. The phosphor can be projected as a useful material in X- and gamma-ray scintillators. [ABSTRACT FROM AUTHOR]

The precursors' purity is one of the main factors when growing crystals with predetermined functional properties. Impurities composition greatly influence optical properties, radiation hardness and decay time of scintillation crystals and directly relates to crystal's own radiation background. On an example of Bi4Ge3O12 (BGO) crystal growth dependence of optical and scintillating properties and radiation hardness from growth technique and the purity of initial bismuth oxide Bi2O3 was shown. In general the goal of obtaining crystals for rear events registration is an even more complex problem. At one hand one has to obtain crystals with the best scintillation properties, at another hand their own radiation background has to be extremely low, especially in a group of elements such as K. Besides that, due to a high cost of isotopically-enriched materials maximal utilization of compound during growth process and recuperation of residuals after growth and cutting with minimal material losses is strictly required. [ABSTRACT FROM AUTHOR]

The plastic scintillators are used in different areas of science and technology. One of the use of these scintillator detectors is as beam loss monitors (BLM) for new generation of high intensity heavy ion in superconducting linear accelerators. Operated in pulse counting mode with rather high thresholds and shielded by few centimeters of lead in order to cope with radiofrequency noise and X-ray background emitted by accelerator cavities, they preserve high efficiency for high energy gamma ray and neutrons produced in the nuclear reactions of lost beam particles with accelerator components. Efficiency calculation and calibration of detectors is very important before their practical usage. In the present work, the efficiency of plastic scintillator detectors is simulated using FLUKA for different gamma and neutron sources like, 60Co, 137Cs and 238Pu-Be. The sources are placed at different positions around the detector. Calculated values are compared with the measured values and a reasonable agreement is observed. [ABSTRACT FROM AUTHOR]

Double beta decay of 116Cd has been investigated with the help of radiopure enriched 116CdWO4 crystal scintillators in the experiment Aurora. The half-life of 116Cd relatively to the 2ν2β decay of 116Cd to the ground level of 116Sn is measured with the highest up-to-date accuracy as T1/2 = [2.69 ± 0.02 (stat.) ± 0.14 (syst.)] × 1019 yr. A new improved limit on the 0ν2β decay of 116Cd to the ground state of 116Sn is set as T1/2 ≥ 2.4 × 1023 yr at 90% C.L., that corresponds to the effective Majorana neutrino mass limit in the range ≤ (1.1 − 1.6) eV, depending on the nuclear matrix elements used in the estimations. New improved limits on other 2β processes in 116Cd (decays with majoron emission, transitions to excited levels of 116Sn) were set at the level of T1/2 ≥ 1021 − 1022 yr. [ABSTRACT FROM AUTHOR]

A scintillating bolometer technology based on 100Mo-enriched lithium molybdate (Li2 100MoO4) crystals has been developed by LUMINEU to search for neutrinoless double-beta (0ν2β) decay of 100Mo. The results of several low temperature tests at underground environments have proved the reproducibility of high detector performance and crystal radiopurity: in particular ∼5–6 keV FWHM energy resolution and at least 9σ rejection of α’s in the vicinity of the 0ν2β decay of 100Mo (3034 keV) and below 10 μBq/kg bulk activity of 228Th and 226Ra. A modest acquired exposure (0.1 kg×yr) is a limiting factor of the LUMINEU experiment sensitivity to the 0ν2β decay half-life of 100Mo (T1/2 ≥ 0.7×1023 yr at 90% C.L.), however the two-neutrino 2β decay has been measured with the best up to-date accuracy, T1/2 = 6.92 ± 0.06(stat.) ± 0.36(syst.)× 1018 yr. The applicability of the LUMINEU technology for a tonne-scale 0ν2β decay bolometric project CUPID is going to be demonstrated by the CUPID-0/Mo experiment with ∼5 kg of 100Mo embedded in forty 0.2 kg Li2 100MoO4 scintillating bolometers. A first phase of the experiment with twenty Li2 100MoO4 detectors is in preparation at the Modane underground laboratory (France) to start by the end of 2017. [ABSTRACT FROM AUTHOR]

The GERmanium Detector Array (gerda) experiment, located at the Gran Sasso underground laboratory in Italy, is one of the leading experiments for the search of 0vββ decay. In Phase II of the experiment 35.6 kg of enriched germanium detectors are operated. The application of active background rejection methods, such as a liquid argon scintillation light read-out and pulse shape discrimination of germanium detector signals, allowed to reduce the background index to the intended level of 10−3 cts/(keV·kg·yr). In the first five month of data taking 10.8 kg yr of exposure were accumulated. No signal has been found and together with data from Phase I a new limit for the neutrinoless double beta decay half-life of 76Ge of 5.3 · 1025 yr at 90% C.L. was established in June 2016. Phase II data taking is ongoing and will allow the exploration of half-lifes in the 1026 yr regime. The current status of data taking and an update on the background index are presented. [ABSTRACT FROM AUTHOR]

An experiment to search for double beta decay in 106Cd is running in the DAMA/CRYS set-up at the Gran Sasso National Laboratory of the INFN (Italy). In this experiment a 106CdWO4 crystal scintillator (215 g) enriched in 106Cd to 66%, used in previous measurements in different configurations, is now in measurement in coincidence with two large volume low background CdWO4 crystal scintillators in close geometry. This further measurement will allow us to reach a sensitivity at the level of the most sensitive double β+ experiments (T1/2 1020-1022 yr) and to explore the region of the theoretical expectations for some decay modes. [ABSTRACT FROM AUTHOR]

For investigation of more optimal characteristics for CaF2 additives for nanocomposite scintillator the dependences of synthesis method and annealing temperature on the X-ray luminescence and decay time for calcium fluoride were studied. The measurements of luminescence properties and luminescence decay parameters are revealed slow and fast components at emission band at 3.4 eV which is due to different self-trapped exciton (STE) states. The complex dependency of redistribution of the luminescence intensity and decay time for several components of X-ray excited luminescence spectra for CaF2 powders in depending on annealing temperature are observed. [ABSTRACT FROM AUTHOR]

This paper summarizes a Photomultiplier-Scintillator diagnostic system for use in our plasma focus experiments at the Center for Plasma Research INTI IU. The system features an anode-grounded high pulse linearity voltage divider and uses NE102A plastic scintillators. It has detected D-D neutrons in INTI plasma focus device with clear and high signal to noise ratio. Neutron TOF of 120 ns has been measured from the time difference between hard x-ray pulse peak and neutron peak time over a flight path of 2.6±0.01 m; giving energy of 2.5±0.1 MeV for these side-on neutrons. [ABSTRACT FROM AUTHOR]