1,248 results
Search Results
2. The analysis of low level gamma-ray activity by scintillation spectrometry
- Author
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Humphreys, D.
- Published
- 2020
3. Design and test of a high-speed flash ADC mezzanine card for high-resolution and timing performance in nuclear structure experiments [Conference Paper]
- Author
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Egea, X., Sanchis, E., Gonzalez, V., Gadea, A., Blasco, J.M., Barrientos, D., Wadsworth, R., Valiente Dobon, J.J., Tripon, M., Boujrad, A., Houarner, C., Jastrzab, M., Blaizot, M., Bourgault, P., De Angelis, G., Erduran, Mustafa Nizamettin, Erturk, S., De France, G., Huyuk, T., Jaworski, G., Di Nitto, A., Nyberg, J., Palacz, M., Pipidis, A., Tarnowski, R., and Triossi, A.
- Subjects
Neutron detectors ,Germanium ,Ultraviolet spectroscopy ,Nuclear physics ,Historic preservation ,Scintillation counters - Abstract
2012 18th IEEE-NPSS Real Time Conference, RT 2012 -- 9 June 2012 through 15 June 2012 -- Berkeley, CA -- 95754 This board will be part of the upgrade for the new electronics for the EXOGAM2 (HP-Ge detector array) and NEDA (BC501A-based neutron detector array), therefore it was necessary to deal with the problem of providing a sampling card with high resolution for new gamma spectroscopy experiments while sampling at very high rates, with a broad bandwidth in order to preserve the shape for further analysis. Pulse shape analysis is of paramount importance in neutron detectors, such as NEDA, based on scintillators that are sensitive to ?-rays as well. High resolution and high speed are often two parameters which conform a trade-off and it is hard to achieve both simultaneously. The aforementioned constraints and the urge of building new sampling electronics to improve the signal analysis in nuclear physics experiments, led to the development of this FADC mezzanine This involves sampling rates up to 250 Msps preserving a high resolution of 11.3 effective bits in order to satisfy the experiment demands. In this work is described the design and the test bench proposed for a proper high speed ADC characterization system and the results obtained up to now. © 2012 IEEE.
- Published
- 2012
4. Isotopic components of low energy light nuclei in cosmic radiation detected with plastic detector. Environmental research papers
- Author
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Beaujean, R
- Published
- 1975
5. Status of the WAND (Waste Assay for Nonradioactive Disposal) project as of July 1997
- Author
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Parker, J
- Published
- 1998
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6. Reactor neutrino physics potentials of cryogenic pure-CsI crystal.
- Author
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Wang, Lei, Li, Guanda, Yu, Zeyuan, Liang, Xiaohua, Wang, Tian'an, Liu, Fang, Sun, Xilei, Guo, Cong, Zhang, Xin, Lei, Yu, and Chen, Yuede
- Subjects
SCINTILLATION counters ,NEUTRINOS ,CRYOELECTRONICS ,PHYSICS ,NEUTRINO scattering ,CRYSTALS ,ELASTIC scattering - Abstract
This paper presents a world-leading scintillation light yield among inorganic crystals measured from a 0.5 kg pure-CsI detector operated at 77 Kelvin. Scintillation photons were detected by two 2-inch Hamamatsu SiPM arrays equipped with cryogenic front-end electronics. Benefiting the light yield enhancement of pure-CsI at low temperatures and the high photon detection efficiency of SiPM, a light yield of 30.1 photoelectrons per keV energy deposit was obtained for X-rays and γ -rays with energies from 5.9 to 59.6 keV. Instrumental and physical effects in the light yield measurement are carefully analyzed. This is the first stable cryogenic operation of kg-scale pure-CsI crystal readout by SiPM arrays at liquid nitrogen temperatures for several days. The world-leading light yield opens a door for the usage of pure-CsI crystal in several fields, particularly in detecting the coherent elastic neutrino-nucleus scattering of reactor neutrinos. The potential of using pure-CsI crystals in neutrino physics is discussed in the paper. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
7. Dual-energy x-ray computed tomography study based on CsI:Tl and LYSO:Ce scintillator combination.
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Xia, Xiaoqin, Hu, Xiaodong, and Zou, Jing
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SCINTILLATORS ,DUAL energy CT (Tomography) ,COMPUTED tomography ,X-rays ,SCINTILLATION counters ,QUANTUM efficiency ,OPTICAL resolution ,IGNEOUS rocks - Abstract
Dual-energy computed tomography (CT) provides a better material classification capability than traditional CT. A scintillator is an essential component that determines the optical resolution, detective quantum efficiency, and energy separation of the dual-layer dual-energy CT system. In this paper, we propose a new dual-layer scintillator combination composed of CsI:Tl and LYSO:Ce for dual-energy CT imaging. The x-ray attenuation physical process of CsI:Tl and LYSO:Ce combination is simulated on Geant4. The energy distribution and luminescence of different thicknesses of the scintillator combination are investigated by simulation experiments. Then, the optimal thicknesses of the combination are designed based on simulation results. Furthermore, a dual-layer dual-energy CT system using the scintillator combination is built, and practical dual-energy imaging experiments are implemented in the system. Simulation results indicate that the CsI:Tl and LYSO:Ce combination can effectively realize dual-energy detection. The optimal thickness is 100 μm for CsI:Tl and 500 μm for LYSO:Ce. Practical experiments show that the dual-energy CT system using the CsI:Tl and LYSO:Ce combination has low noise. Materials of the metal mixture sample and the igneous rock sample are correctly separated using the dual-energy data obtained by the CsI:Tl and LYSO:Ce combination. Therefore, the CsI:Tl and LYSO:Ce combination is expected to be used in dual-energy CT imaging studies of complex materials, such as metals, bones, and rocks. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
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8. Temporal behavior of hard x-ray and neutron production in plasma focus discharges.
- Author
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Kubes, P., Paduch, M., Tomaszewski, K., Sadowski, M. J., Cikhardt, J., Klir, D., Kravarik, J., Malir, J., Munzar, V., Novotný, J., Rezac, K., and Szymaszek, A.
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PLASMA focus ,HARD X-rays ,PLASMA production ,PLASMA flow ,NEUTRONS ,SCINTILLATION counters ,NEUTRON emission - Abstract
This paper concerns the correlation of hard x-ray and neutron signals, which were recorded with scintillation detectors oriented in the axial and radial directions, in a comparison with interferometric and extreme-ultraviolet radiation frames, as recorded within the plasma focus (PF)-1000 facility operated with a deuterium filling. The considered signals showed two different phases. In the initial phase, the fusion neutrons are mainly produced by deuterons moving dominantly downstream during the disruption of a pinch constriction (lasting tens nanoseconds). In the later phase (usually after about 100 ns), the fusion neutron emission reaches its maximum in the radial directions. This emission (lasting 100–200 ns) is caused by the fast deuterons moving in both the downstream and radial directions. It correlates usually with a decay of dense plasma structures in remnants of the expanding pinch column. This can be explained by a decay of internal magnetic fields. The neutron signal is usually composed of several sub-pulses of different energies. It was deduced that the primary deuterons producing the observed fusion neutrons undergo a regular and repeated temporal, directional, and energy evolution. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
9. Angular Distribution of Bremsstrahlung Spectral Temperature Measured in a Full Dimension of ECR Ion Source Using NaI(TI) Detector.
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Kumwenda, Mwingereza J.
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BREMSSTRAHLUNG ,ANGULAR distribution (Nuclear physics) ,ELECTRON cyclotron resonance sources ,MONTE Carlo method ,SCINTILLATION counters - Abstract
Measurement of angular distribution (AD) of the bremsstrahlung spectral temperature from a full dimension of the Electron Cyclotron Resonance Ion Source (ECRIS) along the beam axis is challenging. To overcome some challenges, this paper presents the AD of the bremsstrahlung spectral temperature measured in a full dimension of the ECRIS along the beam axis using data obtained from the Busan Center of Korea Basic Science Institute (KBSI). The bremsstrahlung spectral temperature from 28-GHz ECR Ion source at the KBSI was measured in six, three, and nine azimuthal angles at the injection, centre, and extraction sides of the ECRIS using three round type thallium-activated sodium iodide (NaI(TI)) scintillation detectors. Monte Carlo simulation based on the Geant4 software package was performed to take the geometrical acceptance and energy-dependent detection efficiency into account due to large non-uniformity in the material budget. True bremsstrahlung energy spectra from the 28-GHz ECR ion source were obtained using the inverse-matrix deconvolution method. The unfolding method was based on a full geometry of the Geant4 model of the ECRIS plasma. The results show that in all three measurement locations, the highest value of the spectral temperature was at an angle of 30° coincident with one of the maximum angles of the ECRIS plasma shape. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
10. Specially developed LR-0 reactor graphite environment for gen IV reactor support and cross-section measurement.
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Peltan, Tomas, Vilimova, Eva, Czakoj, Tomas, Matej, Zdenek, Mravec, Filip, Cvachovec, Frantisek, Simon, Jan, Juricek, Vlastimil, and Kostal, Michal
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NUCLEAR reactors ,GRAPHITE ,SCINTILLATION counters ,NEUTRONS ,ATOMS - Abstract
This paper is focused on the development of the experimental environment connected to reactor graphite. Regarding its very good neutronic and mechanical properties, graphite will be very important in some new reactor designs, such as high-temperature or molten salt SMR reactors. These new reactor concepts require a new experimental environment as support for further research. In the laboratories of the Research Centre Řež and at the LR-0 reactor, the new experimentally validated graphite environment was created. This large graphite insertion is the largest graphite mono-block, which is possible to assemble at the LR-0 reactor. Sets of experiments for measuring reaction rates of different activation detectors for neutron field mapping were performed. This approach was used for thermal and epithermal region descriptions. For the fast neutron spectrum evaluation, the stilbene scintillation detector was used. All parameters, such as criticality height of moderator level, neutron spectrum, and other parameters for all experiments, were performed using Monte Carlo neutronic codes Serpent and MCNP. The obtained results were finally compared to the measurement of neutron leakage spectra from the graphite cube and graphite cylinder. These specially developed graphite-shaped neutron fields, reactor insertions, and external cube and cylinder with Cf neutron source can be used in the future for validation of not only materials used in SMR reactors but for arbitrary cross-section verification. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
11. Effect of Plasma Treatment on the Luminescent and Scintillation Properties of Thick ZnO Films Fabricated by Sputtering of a Hot Ceramic Target.
- Author
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Tarasov, Andrey P., Ismailov, Abubakar M., Gadzhiev, Makhach Kh., Venevtsev, Ivan D., Muslimov, Arsen E., Volchkov, Ivan S., Aidamirova, Samira R., Tyuftyaev, Alexandr S., Butashin, Andrey V., and Kanevsky, Vladimir M.
- Subjects
THICK films ,ZINC oxide films ,SCINTILLATION counters ,CERAMICS ,SCINTILLATORS ,LUMINESCENCE ,MAGNETRON sputtering - Abstract
The paper presents the results of a comprehensive study of the structural-phase composition, morphology, optical, luminescent, and scintillation characteristics of thick ZnO films fabricated by magnetron sputtering. By using a hot ceramic target, extremely rapid growth (~50 µm/h) of ZnO microfilms more than 100 µm thick was performed, which is an advantage for the industrial production of scintillation detectors. The effects of post-growth treatment of the fabricated films in low-temperature plasma were studied and a significant improvement in their crystalline and optical quality was shown. As a result, the films exhibit intense near-band-edge luminescence in the near-UV region with a decay time of <1 ns. Plasma treatment also allowed to significantly weaken the visible defect luminescence excited in the near-surface regions of the films. A study of the luminescence mechanisms in the synthesized films revealed that their near-band-edge emission at room temperature is formed by phonon replicas of free exciton recombination emission. Particularly, the first phonon replica plays the main role in the case of optical excitation, while upon X-ray excitation, the second phonon replica dominates. It was also shown that the green band peaking at ~510 nm (2.43 eV) is due to surface emission centers, while longer wavelength (>550 nm) green-yellow emission originates mainly from bulk parts of the films. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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12. Photomultiplier tube signal conditioning for high-temperature applications.
- Author
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Zezuliński, Kacper, Broslawski, Andrzej, Slipukhin, Ivan, Guzik, Zbigniew, Krakowski, Tomasz, Burakowski, Szymon, Kaźmierczak, Łukasz, Łubian, Grzegorz, Milewski, Piotr, Saworska, Gabriela, and Trela, Krystian
- Subjects
PHOTOMULTIPLIERS ,SIGNAL processing ,NUCLEAR counters ,IONIZING radiation ,SCINTILLATION counters ,POWER resources - Abstract
Ionizing radiation detection in harsh environment conditions often requires additional signal processing to match the requirements of the commercial data readout systems. The subject of this paper is the design of the high-temperature (HT) signal conditioning module that ensures the applicability of scintillation detectors that utilize photomultiplier tubes (PMT) with moderate sampling rate instrumentation. The design was developed for the operation in HT environments (up to 120°C). In order to achieve the optimal signal shape, the module combines a charge amplifier and a low-pass filtering circuitry. An embedded power supply section makes it a complete, standalone unit requiring a single 12 V supplying line. A comprehensive analysis of the developed device, named "PreAmp Shape", was conducted in order to prove the intended functionality over the different working conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
13. Multiple scatter correction for single plane Compton camera imaging in nuclear decommissioning.
- Author
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Burger, Martin, Jansen, Sven, Hölzer, Karsten, Kaden, Thomas, Kuger, Lorenz, Lösch, Henry, Petrak, Sybille, Rieger, Tobias, and Schönmuth, Thomas
- Subjects
- *
MULTIPLE scattering (Physics) , *COMPTON imaging , *SCINTILLATION counters , *GAMMA rays , *DETECTORS - Abstract
This paper focuses on the application of Compton cameras in nuclear decommissioning, aiming to develop efficient and affordable radiological characterization methods. Compton cameras offer advantages over traditional Anger cameras, including increased sensitivity and a larger field of view. We showcase the use of monolithic scintillation detectors in a Compton camera setup to compute two‐dimensional reconstructions of the source location of incident gamma rays. The presence of multiple scattering effects in the large, spatially non‐resolved detectors can lead to spatial artifacts in the reconstructed source activity. To address this, the paper proposes an extended forward model that accounts for double scattering interactions within a single detector element. Experimental and simulation results demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
14. Forward modeling of pile-up events in liquid scintillator detectors for neutron emission spectroscopy.
- Author
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Sahlberg, A., Eriksson, J., Conroy, S., Ericsson, G., Hägg, L., Giacomelli, L., and Belli, F.
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NEUTRON counters ,LIQUID scintillators ,NEUTRON emission ,EMISSION spectroscopy ,NEUTRON spectroscopy ,SCINTILLATORS ,SCINTILLATION counters - Abstract
When using liquid scintillator detectors to measure the neutron emission spectrum from fusion plasmas, the problem of pile-up distortion can be significant. Because of the large neutron rates encountered in many fusion experiments, some pile-up distortion can remain even after applying traditional pile-up elimination methods, which alters the shape of the measured light-yield spectrum and influences the spectroscopic analysis. Particularly, pile-up events appear as a high-energy tail in the measured light-yield spectrum, which obfuscates the contribution that supra-thermal ions make to the energy spectrum. It is important to understand the behavior of such "fast ions" in fusion plasmas, and it is hence desirable to be able to measure their contribution to the neutron spectrum as accurately as possible. This paper presents a technique for incorporating distortion from undetected pile-up events into the analysis of the light-yield spectrum, hence compensating for pile-up distortion. The spectral contribution from undetected pile-up events is determined using Monte Carlo methods and is included in the spectroscopic study as a pile-up component. The method is applied to data from an NE213 scintillator detector at JET and validated by comparing with results from the time-of-flight spectrometer TOFOR, which is not susceptible to pile-up distortion. Based on the results, we conclude that the suggested analysis method helps counteract the problem of pile-up effects and improves the possibilities for extracting accurate fast-ion information from the light-yield spectrum. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
15. Growth and Evaluation of Improved CsI:Tl and NaI:Tl Scintillators.
- Author
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Hawrami, Rastgo, Ariesanti, Elsa, Farsoni, Abi, Szydel, Diane, and Sabet, Hamid
- Subjects
SODIUM iodide ,SCINTILLATORS ,CESIUM iodide ,DECAY constants ,PHOTOMULTIPLIERS ,SCINTILLATION counters - Abstract
Scintillators play an important role in radiation detection and imaging. Thallium-doped cesium iodide (CsI:Tl) and sodium iodide (NaI:Tl) are two of the major scintillators that have been used for many applications for many decades. In this paper, we will present an improved scintillation performance of Bridgman method-grown CsI(Tl) and NaI(Tl) crystals developed by Xtallized Intelligence, Inc. (XI, Inc.), and we will compare the performance with commercially available CsI:Tl and NaI:Tl. In a preliminary testing using MicroFJ−60035−TSV silicon photomultipliers (ON Semiconductor), the newly developed and improved 12.5 × 12.5 × 6 mm
3 CsI:Tl crystal has shown an energy resolution of 4.8% (FWHM) at 662 keV, compared to 7.2% obtained by a commercially available CsI:Tl with a size of 12.5 × 12.5 × 25 mm3 . The energy resolution of 5.4% (FWHM) at 662 keV is obtained for the newly improved NaI:Tl crystal, compared to 7% obtained by a commercially available ∅1″ × 1″ NaI(Tl). The comparison of the photo peak channel locations shows that the improvements in both CsI:Tl and NaI:Tl, developed by XI, Inc., have produced much larger signal amplitudes (roughly double), when compared to the commercially available CsI(Tl) and NaI:Tl. Improved decay time constants are presented as well. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
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16. Development of the SPD Beam–Beam Counter Scintillation Detector Prototype with FERS-5200 Front-End Readout System.
- Author
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Tishevsky, A. V., Dubinin, F. A., Isupov, A. Yu., Ladygin, V. P., Nigmatkulov, G. A., Reznikov, S. G., Teterin, P. E., Volkov, I. S., Zakharov, A. M., and Zhurkina, A. O.
- Subjects
- *
COSMIC rays , *SCINTILLATION counters , *POLARIMETRY , *DETECTORS , *PHYSICS - Abstract
The Spin Physics Detector is an experiment at NICA designed to study the spin structure of the proton and deuteron and the other spin-related phenomena using polarized beams. The collision energy is up to 27 GeV and the luminosity is up to 10 cm s in pp mode. Two scintillator-based detectors, Beam–Beam Counters (BBC), will be installed upstream and downstream the interaction point and will serve as a tool for beam diagnostics including local polarimetry. In this paper, we present the design of the BBC prototype based on the tiles with green WLS and SensL SiPM readout. FERS-5200 is used as the front-end readout system. The amplitude and timing resolutions for different tiles using radioactive source and cosmic rays are obtained. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
17. Characterization of diamond and organic scintillation detectors utilizing radiation sources for continuous plasma operation.
- Author
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Iliasova, M. V., Mirfayzi, S. R., Rajput, M., Chandrasekhar, K., Fontana, M., Hoffman, D., O'Gorman, T., Kamal, G., McNamara, S. A. M., Sertoli, M., Sridhar, S., Varje, J., Wilson, C., Zakhar, D., and Naylor, G.
- Subjects
- *
SCINTILLATION counters , *NUCLEAR counters , *FORM perception , *NEUTRON counters , *NEUTRON flux - Abstract
This paper provides a comprehensive study of neutron calibration methodologies, specifically highlighting the capabilities for n–γ discrimination in diamond and EJ-309, and stilbene scintillation detectors. The calibration process detailed in this study includes pulse height analysis and pulse shape discrimination, relying on the analysis of charge deposition resulting from both γ and neutron interactions. Utilizing 60Co and 252Cf radiation sources, the energy spectra of these sources are obtained. The characterized detectors were used in ST40 experiments and allowed acquiring neutron signal during a plasma shot with good agreement among diamond and scintillation detectors. Then, the diamond detector was cross-calibrated against indium activation foils placed at the same location in proximity to the ST40 during plasma shots: both detectors measured a neutron flux of ≈106 cm−2 s−1 at ≈1 m distance from the tokamak center, and the discrepancy between the diamond detector and the activation foils is ≈25%. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
18. Fast neutron and γ-ray backscatter radiography for the characterization of corrosion-born defects in oil pipelines.
- Author
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Lyoussi, A., Giot, M., Carette, M., Jenčič, I., Reynard-Carette, C., Vermeeren, L., Snoj, L., Le Dû, P., Licata, Mauro, Parker, Helen M. O., Aspinall, Michael D., Bandala, Manuel, Cave, Frank, Conway, Sebastian, Gerta, Domas, and Joyce, Malcolm J.
- Subjects
FAST neutrons ,ORGANIC scintillators ,SCINTILLATION counters ,SPONTANEOUS fission - Abstract
In this research, a combined fast-neutron/γ-raybackscatter imaging technique is described. The aim of this work is to understand corrosion defects in pipelines by measuring differences in the scattered radiation flux, generated when different steel thicknesses are irradiated by a neutron and γ-ray focused beam. A californium-252 radiation source is used to produce fast neutron and γ rays, exploiting its spontaneousfission. This mixed radiation field is collimated and directed towards the steel samples. Backscattered neutrons and γ rays aremeasured as a function of the steel thickness using 4 liquid organic scintillation detectors linked to a real-time, pulse-shape discrimination system, which separates and retains the neutron and γ-ray event data. In this paper, we describe how, using asingle radiation source and detection system, it is possible to perform and combine two complementary imaging modalities. This research is validated by an MCNP6 computer simulation study. The backscatter imaging system developed for this research and the experimental results of the measurements carried out using the National Physical Laboratory neutron low-scatter facility are also presented in this paper. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
19. Promising Detector Concepts to Advance Coincidence Time Resolution for Time-of-Flight Positron Emission Tomography.
- Author
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LEVIN, C. S.
- Subjects
POSITRON emission tomography ,COINCIDENCE ,DETECTORS ,SCINTILLATION counters ,POSITRON annihilation ,POSITRON emission - Abstract
In this paper, we describe design considerations and promising detector technologies for time-of-flight positron emission tomography (TOF-PET). During a positron emission tomography scan, TOF-PET enables positron annihilation events to be positioned closer to their true origin along system response lines, thus facilitating improved reconstructed image signal-to-noise ratio, which has benefits such as better disease visualization and quantification, lower injected dose, and/or lower study duration. The degree of this image signal-to-noise ratio boost is determined by the annihilation photon pair coincidence time resolution of the detector system. Thus, there has been much research and development to advance detector coincidence time resolution, which is the foundation for future TOF-PET system designs. But when considering novel TOF-PET detector designs, it is important to select approaches that enhance coincidence time resolution without a tradeoff of decreasing detection efficiency (e.g., employing thin or low-density detector materials or low intra- or inter-module packing fraction, etc.). One might even argue that high coincidence detection efficiency (a.k.a. sensitivity) is the primary goal of any new positron emission tomography system design. In this paper, we will briefly discuss fundamental limitations on positron emission tomography coincidence time resolution using scintillation detectors and describe new detector configurations and electronic readout designs that attempt to address those constraints and achieve as low as 100 ps coincidence time resolution without compromising overall detection efficiency. We also concisely describe an innovative, non-scintillation-based, fast detection concept, which borrows ideas from the field of optics and could, in theory, achieve ~ 1 ps coincidence time resolution. If successful, these technologies will lead to next-generation systems that enhance TOF-PET's ability to visualize and quantify disease. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
20. EVALUATION OF LIQUID-GAS FLOW IN PIPELINE USING GAMMA-RAY ABSORPTION TECHNIQUE AND ADVANCED SIGNAL PROCESSING.
- Author
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Hanus, Robert, Zych, Marcin, Mosorov, Volodymyr, Golijanek-Jędrzejczyk, Anna, Jaszczur, Marek, and Andruszkiewicz, Artur
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SIGNAL processing ,SCINTILLATION counters ,POROSITY ,ARTIFICIAL neural networks ,PIPELINES ,NUCLEAR activation analysis ,NATURAL gas pipelines - Abstract
Liquid-gas flows in pipelines appear in many industrial processes, e.g. in the nuclear, mining, and oil industry. The gamma-absorption technique is one of the methods that can be successfully applied to study such flows. This paper presents the use of the gamma-absorption method to determine the water-air flow parameters in a horizontal pipeline. Three flow types were studied in this work: plug, transitional plug-bubble, and bubble one. In the research, a radiometric set consisting of two Am-241 sources and two NaI(TI) scintillation detectors have been applied. Based on the analysis of the signals from both scintillation detectors, the gas phase velocity was calculated using the cross-correlation method (CCM). The signal from one detector was used to determine the void fraction and to recognise the flow regime. In the latter case, a Multi-Layer Perceptron-type artificial neural network (ANN) was applied. To reduce the number of signal features, the principal component analysis (PCA) was used. The expanded uncertainties of gas velocity and void fraction obtained for the flow types studied in this paper did not exceed 4.3% and 7.4% respectively. All three types of analyzed flows were recognised with 100% accuracy. Results of the experiments confirm the usefulness of the gamma-ray absorption method in combination with radiometric signal analysis by CCM and ANN with PCA for comprehensive analysis of liquid-gas flow in the pipeline. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
21. Identification of nuclear wastage with the help of scintillation detectors.
- Author
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Garg, Kajal and Bhatnagar, Sonali
- Subjects
COSMIC ray muons ,COSMIC rays ,MUONS ,SCINTILLATION counters ,RADIOACTIVE wastes ,RADIOACTIVE substances ,ENERGY dissipation ,ATMOSPHERE - Abstract
This paper explains the use of muon tomography in imaging the dry storage container to detect the high radioactive material in it. Cosmic ray muon is a natural source in the Earth's atmosphere and has high penetrating power and large scattering angle for high Z materials. In this paper, we have designed a dry storage container inside which UO 2 rods have been placed and on increasing the number of these rods muon scattering has been observed. We have shown that as the muons entered into the container, it generates a scattering pattern and from that pattern, we can find the existence of any nuclear waste in it accurately without opening it. Some other parameters such as energy loss, radiation length and scattering angle have also been calculated for 3 GeV–10 GeV muon energy. The results for 3 GeV energy has been compared with C Jewett et al and further extrapolated to higher energies. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
22. Current Status of the Novel 3D SuperFGD Detector for the T2K Experiment.
- Author
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Dergacheva, Anna, Chernov, Denis, Chvirova, Angelina, Erofeev, Gleb, Fedorova, Daria, Fedotov, Sergei, Khabibullin, Marat, Khotjantsev, Alexei, Kudenko, Yury, Mefodiev, Alexander, Mineev, Oleg, and Yershov, Nikolai
- Subjects
LIGHT emitting diodes ,DETECTORS ,GRAIN size ,SCINTILLATORS ,SCINTILLATION counters - Abstract
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]
- Published
- 2023
- Full Text
- View/download PDF
23. Performance of HQAM/XQAM Laser Communication System in Anisotropic Non-Kolmogorov Ground–HAP–Satellite Uplink.
- Author
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Jiang, Xuewen, Wang, Yi, and Lu, Wangyue
- Subjects
LASER communication systems ,QUADRATURE amplitude modulation ,TELECOMMUNICATION satellites ,TRANSMITTERS (Communication) ,BIT error rate ,MONTE Carlo method ,TELECOMMUNICATION systems ,SCINTILLATION counters - Abstract
Satellite laser communication can achieve high-speed, high-precision, and high-security broadband communication without being constrained by the electromagnetic spectrum, which has attracted attention. So, this paper proposes the use of a high-altitude platform (HAP) under anisotropic non-Kolmogorov turbulence to improve the communication performance of the system. Cross quadrature amplitude modulation (XQAM) and hexagon quadrature amplitude modulation (HQAM) are applied to the ground–HAP–satellite (G-H-S) laser communication system. Considering the combined effects of uplink light intensity scintillation, beam wander, and the angle of arrival fluctuation, the G-H-S system's bit error rate (BER) closure expression is derived under the EW distribution. Simultaneously, the relationship between the G-H-S system's signal-to-noise ratio (SNR) and BER under different anisotropic factor u values is simulated and compared with the traditional ground–satellite (G-S) system. The results show that the communication performance of the G-H-S system with HQAM modulation is better. In addition, the effects of the zenith angle, receiving aperture, transmitter beam radius, and beam divergence angle on the BER performance of the system are also studied. Finally, the correctness of the analysis results is verified via Monte Carlo simulation. This research will benefit the design and optimization of satellite laser communication systems. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
24. Evaluation of the responses of the NuDET neutron detector in the Mini Labyrinth experiment.
- Author
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Čerba, Štefan, Vrban, Branislav, Lüley, Jakub, Filová, Vendula, Nečas, Vladimír, Štastný, Ondřej, Katovský, Karel, Gloginjic, Marko, Mravik, Željko, Erich, Marko, and Petrovic, Srdjan
- Subjects
SCINTILLATION counters ,NEUTRON counters ,NEUTRON sources ,CONCRETE blocks ,COMPUTER programming ,NEUTRONS ,DETECTORS - Abstract
The Mini Labyrinth experiment is a simple neutron and gamma shielding experiment developed at Slovak University of Technology (STU), inspired by the ALARM-CF-AIR-LAB-001 ICSBEP benchmark. Compared to the original Labyrinth, which was made from concrete blocks and had dimension of several meters, the STU Mini Labyrinth is approximately ten times smaller and consists of NEUTRONSTOP shielding blocks. So far, several versions and modifications of the Mini Labyrinth have been investigated, currently the V2-25-L version is used for code evaluation. This version uses a PuBe neutron source loaded in the entrance of the Mini Labyrinth, a plastic tank filled with light water moderator and the NuDET plastic scintillation neutron detector, which can be placed around the experimental workplace. This detector has a significant role in the experiment since it is a calibration apparatus and provides real time data on the rates of ambient dose equivalents of neutron radiation. On the other hand, as it is a certified commercial product, the response function of this detector is unknow, which makes a significant challenge of verifying the measured data with computer codes. This paper presents a result of a series of measurements with the NuDET detector performed at STU and discusses the options, how to verify the experimental results by the SCALE6 system in the most effective way. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
25. Scintillation Detector Timing Resolution; A Study by Ray Tracing Software.
- Author
-
ter Weele, David N., Schaart, Dennis R., and Dorenbos, Pieter
- Subjects
SCINTILLATION counters ,TIME-of-flight measurements ,POSITRON emission tomography ,PHOTONS ,NESOSILICATES ,OPTICAL resolution ,COMPUTER software - Abstract
Time-of-flight positron emission tomography requires high timing resolution. In this paper, we determined the influence of scintillation properties on the detector timing resolution for crystals with non-negligible optical transit timespread. In addition to intrinsic scintillation properties, such as the light yield, decay time constant, and scintillation rise time, we also studied the relation between the timing resolution and extrinsic scintillation properties, such as the dimensions of the crystal, the absorption probability of the reflector, the dwell time of photons inside the reflector during the reflection process, and the crystal polish. For this purpose, we developed ray-tracing software. The crystals simulated in this paper are LSO:Ce, LYSO:Ce, LSO:Ce,0.2%Ca, LYSO:0.11%Ce,0.2%Mg, and LYSO:0.2%Ce,0.2%Ca, with dimensions 3 \times 3 \times 5~\mm^3, 3 \times 3 \times 10~\mm^3, 3 \times 3 \times 20~\mm^3, and 4 \times 4 \times 22~\mm^3. We furthermore studied the optical transit timespread of photons inside polished and etched crystals, which explains the differences in timing resolution. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
26. Inhibition of Synthesis of Peroxidases and Some Proteins by Heliangine in Phaseolus mungo Hypocotyl Sections
- Author
-
ANZAI, TADASHI
- Published
- 1975
27. Statistical Studies of Fading in Underwater Wireless Optical Channels in the Presence of Air Bubble, Temperature, and Salinity Random Variations.
- Author
-
Jamali, Mohammad Vahid, Mirani, Ali, Parsay, Alireza, Abolhassani, Bahman, Nabavi, Pooya, Chizari, Ata, Khorramshahi, Pirazh, Abdollahramezani, Sajjad, and Salehi, Jawad A.
- Subjects
OPTICAL signal detection ,OPTICAL communications ,DATA transmission systems ,REFRACTIVE index ,SCINTILLATION counters - Abstract
Optical signal propagation through underwater channels is affected by three main degrading phenomena, namely, absorption, scattering, and fading. In this paper, we experimentally study the statistical distribution of intensity fluctuations in underwater wireless optical channels with random temperature and salinity variations, as well as the presence of air bubbles. In particular, we define different scenarios to produce random fluctuations on the water refractive index across the propagation path and, then, examine the accuracy of various statistical distributions in terms of their goodness of fit to the experimental data. We also obtain the channel coherence time to address the average period of fading temporal variations. The scenarios under consideration cover a wide range of scintillation index from weak to strong turbulence. Moreover, the effects of beam-expander-and-collimator (BEC) at the transmitter side and aperture averaging lens (AAL) at the receiver side are experimentally investigated. We show that the use of a transmitter BEC and/or a receiver AAL suits single-lobe distributions, such that the generalized Gamma and exponentiated Weibull distributions can excellently match the histograms of the acquired data. Our experimental results further reveal that the channel coherence time is on the order of 10−3 s and larger which implies to the slow fading turbulent channels. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
28. Feasibility Study of an Alcohol-Based Liquid Scintillation Detector and Its Application.
- Author
-
Kim, Byoung Chan, Choi, Ji Young, Joo, Kyung Kwang, Park, Seon Yeong, Song, Ye Sung, and Woo, Hee Jin
- Subjects
SCINTILLATION counters ,LIQUID scintillators ,PARTICLE detectors ,ELECTRON beams ,COMPUTED tomography ,SCINTILLATORS ,MONTE Carlo method - Abstract
This paper proposes a new base material, a mixture of alcohol and water, for liquid scintillators. A possibility of using alcohol as a new detection solution in a particle detector is described. A liquid scintillator is widely used in various fields because of its high light yield. In addition, it is very important to develop a stable liquid scintillator for particle detectors or other medical applications. To date, there have been no previous R&D studies elsewhere for the use of alcohol in particle detectors, and no market products are available of this type. Thus, there is a room for improvement. This paper describes the brief synthesizing process of the alcohol-based liquid scintillator by varying the mixing ratio of each component that makes up the liquid scintillator. The several feasible physical and optical properties of an alcohol-based liquid scintillator were investigated and presented. Finally, as one of its applications, a range (beam-path length) measurement using an electron beam in medical physics is introduced after irradiating an alcohol-based liquid scintillator with electron beam energies of 6~12 MeV. The measurement results were compared with a Monte Carlo simulation, Novalis Tx, a phantom, and a CT image. In the near future, the new alcohol-based liquid scintillator could be used for particle detector or medical imaging applications. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
29. Crystal growth, luminescence, and scintillation properties of Zn2Te3O8 crystal for 0νββ decay search.
- Author
-
Khan, Arshad, Kim, H. J., Kim, Yeongduk, Lee, Moo Hyun, Abdalla, Ayman M., and Algethami, Jari S.
- Subjects
SCINTILLATORS ,CRYSTAL growth ,PHASE transitions ,LUMINESCENCE ,SCINTILLATION counters ,CRYSTALS ,BAND gaps - Abstract
A single crystal of Zn
2 Te3 O8 (ZTO) was grown using the conventional Czochralski technique. TGA analysis showed that the melting point of ZTO is 681 °C, while it exhibits a structural phase transition at 621 °C. The powder X-ray diffraction analysis of ZTO confirmed that it possesses a single crystalline monoclinic structure with the C2/c space group. An indirect band gap of 3.75 eV was estimated for the ZTO crystal based on its absorption spectrum. The X-ray-induced luminescence of the grown crystal comprised a broad band peaking at 565 nm, which can be tentatively assigned to the self-trapped exciton emission from the (Te3 O8 )4− molecular complexes. The photoluminescence measured under 280 nm excitation showed a broad band luminescence peaking at about 600 nm, and its intensity was significantly enhanced upon cooling the crystal from 300 K to 10 K. The photoluminescence decay time under 280 nm excitation was shown to have two exponential components in the range from 10 K to 175 K, which became a single exponential upon further heating the crystal. Low scintillation light was observed at room temperature both under α- and β-particle excitations from241 Am and90 Sr sources, respectively. The scintillation light yield measured under β-particle excitation from the90 Sr source was enhanced by about five orders of magnitude at 10 K in comparison to that at 300 K. The scintillation light yield measured at 10 K under the same experimental conditions for ZTO in comparison with the well-known cryogenic scintillator Li2 MoO4 (LMO) was shown to have four times higher scintillation light. A single-crystal ingot of ZTO was obtained for the first time; however, it had several cracks due to its phase transition. Notably, scintillation at low temperatures for a Te-based crystal was observed for the first time. These preliminary findings are very promising and show that ZTO will be a good candidate for cryogenic phonon scintillation detectors for the 0νββ decay search of130 Te. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
30. Scintillation Detector Prototype for a Beam–Beam Counter at NICA SPD.
- Author
-
Tishevsky, A. V., Alekseev, I. G., Volkov, I. S., Gurchin, Yu. V., Isupov, A. Yu., Kulevoy, T. V., Ladygin, V. P., Polozov, P. A., Reznikov, S. G., Svirida, D. N., Terekhin, A. A., and Khrenov, A. N.
- Subjects
SCINTILLATION counters ,PROTOTYPES ,DATA acquisition systems ,DETECTORS ,POLARIMETRY - Abstract
The Beam–Beam Counter of the spin physics detector at NICA is proposed for local polarimetry and luminosity monitoring. The main option of the Beam-Beam Counter is the scintillation tiles with SiPM readout. In this paper, we present the results of studies of a scintillation detector prototype using two types of primary electronics. An estimation of the time resolution using the procedure for correcting the "time-walking" effect is discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
31. Measurements of Dispersed Phase Velocity in Two-Phase Flows in Pipelines Using Gamma-Absorption Technique and Phase of the Cross-Spectral Density Function.
- Author
-
Hanus, Robert, Zych, Marcin, and Golijanek-Jędrzejczyk, Anna
- Subjects
PHASE velocity ,FLOW velocity ,GAMMA rays ,SCINTILLATION counters ,GAMMA ray sources ,TWO-phase flow - Abstract
This paper concerns the application of the gamma radiation absorption method in the measurements of dispersed phase velocity in two-phase flows: liquid–gas flow in a horizontal pipeline and liquid–solid particles in a vertical pipe. Radiometric sets containing two linear
241 Am gamma radiation sources and two NaI(Tl) scintillation detectors were used in the research. Due to the stochastic nature of the signals obtained from the scintillation probes, statistical methods were used for their analysis. The linear average velocity of the dispersed phase transportation was calculated using the phase of the cross-spectral density function of the signals registered by the scintillation detectors. It is shown that in the presented cases, the phase method can be more accurate than the most commonly used classical cross-correlation one. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
32. Performance of novel VUV-sensitive Silicon Photo-Multipliers for nEXO.
- Author
-
Gallina, G., Guan, Y., Retiere, F., Cao, G., Bolotnikov, A., Kotov, I., Rescia, S., Soma, A. K., Tsang, T., Darroch, L., Brunner, T., Bolster, J., Cohen, J. R., Franco, T. Pinto, Gillis, W. C., Smalley, H. Peltz, Thibado, S., Pocar, A., Bhat, A., and Jamil, A.
- Subjects
NEUTRINOLESS double beta decay ,PHOTON detectors ,SCINTILLATION counters ,SCINTILLATORS - Abstract
Liquid xenon time projection chambers are promising detectors to search for neutrinoless double beta decay (0 ν β β ), due to their response uniformity, monolithic sensitive volume, scalability to large target masses, and suitability for extremely low background operations. The nEXO collaboration has designed a tonne-scale time projection chamber that aims to search for 0 ν β β of 136 Xe with projected half-life sensitivity of 1.35 × 10 28 yr. To reach this sensitivity, the design goal for nEXO is ≤ 1% energy resolution at the decay Q-value ( 2458.07 ± 0.31 keV). Reaching this resolution requires the efficient collection of both the ionization and scintillation produced in the detector. The nEXO design employs Silicon Photo-Multipliers (SiPMs) to detect the vacuum ultra-violet, 175 nm scintillation light of liquid xenon. This paper reports on the characterization of the newest vacuum ultra-violet sensitive Fondazione Bruno Kessler VUVHD3 SiPMs specifically designed for nEXO, as well as new measurements on new test samples of previously characterised Hamamatsu VUV4 Multi Pixel Photon Counters (MPPCs). Various SiPM and MPPC parameters, such as dark noise, gain, direct crosstalk, correlated avalanches and photon detection efficiency were measured as a function of the applied over voltage and wavelength at liquid xenon temperature (163 K). The results from this study are used to provide updated estimates of the achievable energy resolution at the decay Q-value for the nEXO design. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
33. Development of a Dual-Modality Gamma-ray/Fast Neutron Imaging System for Air Cargo Inspection.
- Author
-
Park, Jae Yeon, Mun, Jungho, Lee, Jae Hyun, Yeon, Yeong-Heum, Chae, Moonsik, Lee, Minwoong, and Lee, Nam-Ho
- Subjects
AIR freight ,IMAGING systems ,NEUTRON generators ,NUCLEAR counters ,NUCLEAR research ,FAST neutrons ,SCINTILLATION counters - Abstract
High-energy radiation sources have provided a strong security inspection capability using a non-invasive imaging system. The use of multiple radiation sources in one imaging system can also lead to a more powerful system that can classify various materials compared to using a single radiation source. The Advanced Radiation Technology Institute of Korea Atomic Energy Research Institute has developed an air cargo inspection system using multiple radiation sources such as fast neutrons and gamma-rays to classify the plastics, metals, and organics among various sample materials. The fast neutron beam with an energy of 14.1 MeV, generated using the D-T neutron generator, and the gamma-ray beam with an energy of 6 MeV, generated by an electron linear accelerator, are projected onto the vertically aligned scintillator-based radiation detectors. The neutron and gamma-ray images of a cargo container moved by a motorized linear translation stage are acquired, and the image data processing shows good material classification results. In this paper, we describe a multi-radiation imaging system for air cargo inspection and investigate its material classification capability using various sample materials. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
34. Design of a reliable numerical model of a plastic scintillation detector for beta spectrometry.
- Author
-
Fleres, L., Venara, J., Cuozzo, M., Mahe, C., Fargier, S., El Haber, E., and Carrel, F.
- Subjects
- *
SPECTROMETRY , *SCINTILLATION counters , *DETECTORS , *RADIATION , *BETA rays - Abstract
The accurate measurement of beta emitters is of utmost importance in various fields, including environmental monitoring, radiation protection and dismantling and decommissioning (D&D) operations. Nondestructive measurement techniques are crucial as they enable assessments of radioactivity without causing further harm or releasing additional hazardous materials. Due to the limited range of beta particles in matter, their characterization requires measurements in contact with the source term. In this paper, we present a study on the performance evaluation of a plastic scintillation detector designed for in-situ beta spectrometry measurements. The MCNP6.2 numerical model of the detector is detailed in the measurement configuration with beta, gamma and internal conversion electrons emitting sources. The calibration process and Gaussian Energy Broadening (GEB) parameters evaluation are discussed. Comparisons between the MCNP6.2 simulations and experimental measurements are exposed, both for gamma and beta spectra. While the gamma-ray detector response shows good agreement, greater discrepancies are observed in the beta ray response. To shed light on these discrepancies, a sensitivity analysis considering various sources of uncertainties is planned for future work. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
35. Salinity and flow pattern independent flow rate measurement in a gas-liquid flow with optimum feature selection and novel detection geometry using ANNs.
- Author
-
ShadSanjabad, Maasoumeh, Feghhi, AmirHossein, Ghaderi, Reza, and Boorboor, Saeed
- Subjects
- *
FLOW measurement , *FEATURE selection , *SCINTILLATORS , *WATER salinization , *SCINTILLATION counters , *SALINITY , *WAVELET transforms - Abstract
This paper presents a study on the salinity determination and flow rate estimation in a two-phase air-water system. For this purpose, an automated air-water test loop capable of generating different flow patterns in a horizontal pathway was utilized to do numerous experiments at varying flow rates. A nuclear measuring setup, comprising Cs-137 and Am-241 as radiation sources, one NaI (Tl) scintillation detector to register transmission counts of Cs and three scintillator detectors for registering transmission and scattering counts from Am, was prepared. A pressure drop pipe was also employed for flow rate measurement, with MLPs were selected as the processing element. Notable innovations of this paper can be considered from two perspectives. Firstly, a novel paradigm in nuclear measurement geometry. This novelty uses the benefits of three scintillator detectors to extract features with the maximum potential for classifying and determining salinity. Secondly, there is a new method in data processing and utilizing optimum features to achieve the best performance in predicting flow rates. Results in flow rate prediction independent of salinity and flow regime indicate that the proposed paradigm and method are reliable for using in industrial fields related to multi-phase metering. • This paper proposes a novel paradigm in nuclear measurement geometry. • This paper employs seven ANNs to develop the optimal prediction model. • The combination of wavelet transform and statistical features shows the best performance to determine the flow rates. • The results indicated that the proposed prediction model achieved an MAE of less than 4/237 L/min and an MRE% of 4/842 % for predicting flow rates. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
36. Ionospheric Scintillation Simulation on Equatorial GPS Signals for Dynamic Platforms.
- Author
-
Jiao, Yu, Rino, Charles, and Morton, Yu T.
- Subjects
IONOSPHERE ,SCINTILLATION counters ,EQUATORIAL satellites ,GLOBAL Positioning System ,GEOMAGNETISM - Abstract
Abstract: This paper presents a physics‐based, data‐consistent, multifrequency GPS scintillation signal simulator for dynamic platforms in the equatorial region. This simulator is based on a two‐dimensional two‐component power‐law phase screen model which is described by a compact set of parameters. The time scale factor is mainly investigated in this paper, which determines the decorrelation time of the simulation signal and is affected by various factors including propagation geometry, irregularity drift velocity, and dynamics of the platform. The comparison between the initialization and simulation data for stationary receivers shows the effectiveness of the simulator. In addition, this paper examines the influence of the platform dynamics on simulation signals with respect to the geomagnetic field direction and the irregularity drift velocity. The simulator presented in this paper will provide a viable tool for dynamic GPS scintillation signal simulation and will aid the design for robust receiver processing algorithms during scintillation for dynamic platforms. © 2018 The Authors. Journal of the Institute of Navigation published by Wiley Periodicals, Inc. on behalf of Institute of Navigation [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
37. Gamma ray detection performance of newly developed MAPD-3NM-II photosensor with LaBr3(Ce) crystal.
- Author
-
Holik, M., Ahmadov, F., Sadigov, A., Ahmadov, G., Berikov, D., Mamedov, F., Naghiyev, J., Stekl, I., Sadygov, Z., Mammadli, A., Garibli, A., Urban, O., and Zich, J.
- Subjects
SENSOR arrays ,SCINTILLATION counters ,SCINTILLATORS ,CRYSTALS - Abstract
This paper presents the gamma-ray detection performance of the newly developed MAPD-3NM-II type SiPM sensor array (4 × 4) with LaBr 3 (Ce) scintillator. The gamma-ray spectra of various sources have been measured in the energy range from 26 keV up to 1332 keV. The newly developed array based on MAPD-3NM-II sensors proved ∼ 22% enhancement in energy resolution in comparison to the former MAPD-3NM-I based array. The energy resolution of 662 keV gamma-rays measured by MAPD-3NM-II was 3.3% while clearly surpassing 4.25% resolution of MAPD-3NM-I predecessor. The enhancement is related to the high PDE of the new MAPD-3NM-II. Obtained results show that the new MAPD-3NM-II demonstrated good energy resolution and linearity in the studied energy region. The energy resolution of the new detector developed based on MAPD-3NM-II was better than all previous products of MAPD. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
38. The effect of scintillator materials on the fast neutron multiplicity measurement.
- Author
-
Li, Kaile, Li, Sufen, Zhang, Quanhu, Cai, Xingfu, and Wang, Fei
- Subjects
NEUTRON multiplicity ,NEUTRON measurement ,FAST neutrons ,SCINTILLATION counters ,NEUTRON counters ,PROTONS ,SCINTILLATORS - Abstract
To analyze the effect of scintillator detectors on the fast neutron multiplicity, this paper uses Geant4 and Matlab to simulate and study three types of scintillator detectors: BC501A, EJ-309 and Stilbene. It's found that EJ-309 has the highest detection efficiency and the smallest measurement deviation. The energy spectrum of the recoil particles is collected to analyze the reason. The results show that Stilbene has the lowest proportion of hydrogen nuclei, which causes poor measurement results. On this basis, we found that a lower carbon: hydrogen molar ratio and a greater density correspond to a better measurement efficiency, and nuclide deuterium has better measurement efficiency than hydrogen nuclide. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
39. 关于加强我国碘化钠伽玛谱仪技术发展的思考.
- Author
-
刘 玮, 韩善彪, 张 伟, and 袁之伦
- Subjects
SODIUM iodide ,SCINTILLATION counters ,RADIATION measurements ,ENVIRONMENTAL protection ,INTERNATIONAL cooperation ,SCINTILLATORS - Abstract
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.)
- Published
- 2022
40. LONG-TERM AFTERGLOW OF SOLID SCINTILLATORS.
- Author
-
Viererbl, Ladislav, Kolros, Antonín, and Vratislavská, Hana Assmann
- Subjects
SCINTILLATORS ,PHOTOMULTIPLIERS ,ULTRAVIOLET lamps ,SCINTILLATION counters ,PHOTODETECTORS - Abstract
Most of scintillators used for radiation detection exhibit afterglow, which is emission of light with longer decay times than that of main light pulse. High signal from afterglow has usually negative influence on detection parameters, e.g. for energy resolution in spectrometry measurements. The paper deals with long-term afterglow of some types of scintillators, which is more significant in the case of integral measurement when current in the photodetector is measured. The range of studied decay times was in the order of tens of seconds to days. Seven types of scintillators were measured: BGO, CaF
2 (Eu), CdWO4 , CsI(Tl), LiI(Eu), NaI(Tl) and plastic scintillator. Excitation of scintillators was made using a UV lamp. After UV irradiation, a scintillator was inserted to scintillation detection unit and the anode current of photomultiplier tube was measured with a picoammeter. As results, CaF2 (Eu) and plastic scintillator have relatively low long-term afterglow signal compared with other measured scintillators. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
41. Characterization of a 109Cd γ-Ray Source for the Two-Phase Argon Detector.
- Author
-
Bondar, A. E., Buzulutskov, A. F., Dolgov, A. D., Legkodymov, A. A., Nosov, V. V., Oleynikov, V. P., Porosev, V. V., Shemyakina, E. O., and Sokolov, A. V.
- Subjects
DETECTORS ,GERMANIUM detectors ,SCINTILLATION counters ,ARGON ,DARK matter ,TUNGSTEN - Abstract
A two-phase argon detector is being developed in our laboratory for dark matter search and low-energy neutrino experiments. A
109 Cd γ-ray source was used to calibrate the energy scale of the detector. In this paper, a detailed emission spectrum of the109 Cd source was measured using a YAP:Ce based scintillation detector and high-purity germanium detector. It was shown that the109 Cd source equipped with a tungsten substrate and a copper filter can provide a complete set of γ-ray lines in the range from 8 to 90 keV for energy calibration of two-phase detectors. These measurements allowed us to successfully quantify the shape of the amplitude spectrum observed when the two-phase detector was irradiated by the109 Cd source. [ABSTRACT FROM AUTHOR]- Published
- 2019
- Full Text
- View/download PDF
42. Joint Time-Reversal Processing and Spatial Diversity for Distributed Target Detection in Shallow Water.
- Author
-
Li, Chunxiao, Pan, Xiang, and Guo, Mingfei
- Subjects
SIGNAL processing ,SIGNAL detection ,UNDERWATER acoustics ,TIME reversal ,WATER waves ,WAVEGUIDES ,DISTRIBUTION (Probability theory) ,COHERENCE (Physics) ,SCINTILLATION counters - Abstract
Due to the high resolution of time reversal processing in a shallow water waveguide, the target can not be treated as a point-like scatterer, but should be modeled as a distributed target composed of elemental scatterers. In this paper, the problem of using multiple focusing on the target to improve the detection performance is investigated. The signal processing method consists of both coherent time-reversal processing and incoherent accumulation of the output of time-reversal processing from each elemental scatterer. The influence of target scintillations on detection using only time reversal processing and the detection performance of joint processing are investigated by a waveguide experiment. The experimental results show that even though the target has a regular aspect, the detection performances differ significantly when different parts of the target are ensonified due to the wave propagation effects in a shallow water waveguide. The effectiveness of incoherent processing that takes advantage of spatial diversity to improve detection performance is also evaluated. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
- View/download PDF
43. Influence of detector resolution on the occurrence of false alarms of radioactive wastewater monitors.
- Author
-
Hinca, Robert and Stribrnsky, Branislav
- Subjects
FALSE alarms ,DETECTORS ,SCINTILLATION counters ,SHOW windows ,BACKGROUND radiation - Abstract
This paper deals with the analysis of the influence of detector resolution on the occurrence of unwanted false alarms caused by natural radiation. A comparison of two compatible scintillation detectors with the same size: 2″×2″ NaI (Tl) and 2″×2″ LaBr
3 (Ce) is given. The main difference between the detectors is in the resolution, which is about 3 times better for LaBr3 (Ce). The work demonstrates a significant impact of using a spectrometric mode of analyzer linked with a good resolution detector. In conclusion a particular analysis of the natural Bi-214 signal proportion in the Cs-137 discriminator windows shows negligible amount of crosstalk for detector resolution below 3.5%. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
44. The comparison of energy resolution fitting functions for 1.5″ NaI:Tl, CsI:Tl, LaBr3:Ce, and CeBr3 scintillation detectors.
- Author
-
Stríbrnský, Branislav and Hinca, Róbert
- Subjects
SCINTILLATION counters ,SODIUM iodide ,ENERGY function ,SCINTILLATORS ,INDUSTRIAL costs ,THALLIUM - Abstract
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 LaBr
3 :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]- Published
- 2021
- Full Text
- View/download PDF
45. Interstellar scintillation observations for PSR J0835−4510 at 6656 MHz.
- Author
-
Xu, Yonghua, Shi, Xun, Lee, Kejia, Hao, Longfei, Li, Zhixuan, Wang, Min, Yuan, Jianping, Xu, Heng, Wu, Ziwei, Jiang, Jinchen, Huang, Yuxiang, Wang, Bojun, Shen, Faxin, and Cao, Shuo
- Subjects
- *
SCINTILLATION counters , *PULSARS , *RADIO telescopes , *CURVATURE - Abstract
Scintillation phenomena of pulsars provide an important tool for studying interstellar scattering screens and their properties. In this paper, we report pulsar scintillation phenomena of the PSR J0835−4510 at multiple epochs between MJD 58592 and MJD 58843 using the Kunming 40 m radio telescope at a centre frequency of 6656 MHz. We have measured the dynamic spectrum, and derived the scintillation time, bandwidth, and secondary spectrum at each observation epoch. For the first time, we report the detection of parabolic arc structure in the secondary spectra of PSR J0835−4510. Parabolic arcs with varying curvatures appear at all our observation epochs. We used both anisotropic and isotropic scattering screen models to fit the annual variations of arc curvature. While both models can fit the arc curvature variations equally well, the anisotropic model also explains the parabolic arc morphology and its time variation. In this model, the scattering is located at a fractional distance of s = 0.35 ± 0.10, or a distance D s = 0.19 ± 0.03 kpc from the Earth, likely corresponding to the boundary of the Local Bubble. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
46. Scintillation and Bit Error Rate Analysis of Lommel Beam.
- Author
-
Bayraktar, Mert
- Subjects
ERROR rates ,BIT error rate ,SIGNAL-to-noise ratio ,SCINTILLATION counters ,ATMOSPHERIC turbulence - Abstract
In this paper, we study on-axis (point like) scintillation, change in scintillation index depending on receiver aperture radius, and bit error rate evaluation of Lommel beam. Scintillation index formula is derived using well known Rytov method and numerical values are evaluated benefiting from random phase screen approach. We investigate that scintillation indexes of all types of Lommel beams are less than Gauss beam. In addition, raise in asymmetry parameter c mitigates on-axis and aperture averaged scintillation. We finally conclude that Lommel beam is well ahead in case of bit error rate(BER) under weak turbulent and low signal to noise ratio(SNR) conditions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
47. Validation of Physics Models of Geant4 Versions 10.4.p03, 10.6.p02 and 10.7.p01 using Data from the CMS Experiment.
- Author
-
Banerjee, Sunanda and Ivanchenko, Vladimir
- Subjects
HADRONS ,LARGE Hadron Collider ,CALORIMETERS ,MONTE Carlo method ,ELECTROMAGNETISM ,SCINTILLATION counters - Abstract
CMS tuned its simulation program and chose a specific physics model of Geant4 by comparing the simulation results with dedicated test beam experiments. Test beam data provide measurements of energy response of the calorimeter as well as resolution for well identified charged hadrons over a large energy region. CMS continues to validate the physics models using the test beam data as well as collision data from the Large Hadron Collider. Isolated charged particles are measured simultaneously in the tracker as well as in the calorimeters. These events are selected using dedicated triggers and are used to measure the response in the calorimeter. Different versions of Geant4 (10.2.p02, 10.4.p03, 10.6.p02) have been used by CMS for its Monte Carlo production and a new version (10.7.p01) is now chosen for future productions. A suitable physics list (collection of physics models) is chosen by optimizing performance against accuracy. A detailed comparison between data and Geant4 predictions is presented in this paper. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
48. First Observations of the New MEXART's Digital System.
- Author
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Gonzalez‐Esparza, J. A., Mejia‐Ambriz, J. C., Aguilar‐Rodriguez, E., Villanueva, P., Andrade, E., Magro, A., Chiello, R., Cutajar, D., Borg, J., and Zarb‐Adami, K.
- Subjects
RADIO telescopes ,SPACE environment ,BEAMFORMING ,SCINTILLATION counters ,ASTROPHYSICS - Abstract
The Mexican Array Radio Telescope (MEXART) is a transit instrument mainly dedicated to performing interplanetary scintillation (IPS) observations with a central operating frequency of 139.65 MHz. The main scientific objective is to perform studies of solar wind properties and space weather effects. MEXART initially operated with an analog beam former (16 × 16 Butler matrix), which produced 16 fixed latitudinal beams. MEXART began operations and reported the first measurements of IPS sources. MEXART's beam forming system had several problems, however. The North‐South beams had poor directivity, with large side lobes, and the instrument did not achieve the expected performance. Therefore, we commissioned the design and construction of a digital back‐end. The digital system solved the problems with the beam forming, increases the bandwidth, and significantly improves the instrument's sensitivity. In this paper, we present the first light of MEXART's digital system. We describe the new technical capabilities of the instrument, and we show some preliminary results: an estimation of the radio telescope's sensitivity (ΔSmin = 2.28 ± 0.23 Jy), the transit of the Galaxy at 140 MHz with the simultaneous tracking of 62 latitudinal beams, and an example of an IPS observation and the single‐station methodology for calculating the solar wind speed. The new technical capabilities of the radio telescope will provide the potential for participating in several scientific studies. These include solar wind properties, space weather forecasting, ionospheric perturbations, and astrophysical aims such as the monitoring of repeating fast radio bursts and pulsars' observations. Key Points: Radio telescope dedicated to the study of solar wind properties and space weather effects using the interplanetary scintillation techniqueThe new digital backend has several beamforming configurations, increases the bandwidth, and improves the instrument's sensitivityWith the new technical capabilities, the instrument can participate in space weather forecasting and other astrophysical studies [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
49. Study of the 16-channel scintillation detector prototype with silicon photomultipliers readout.
- Author
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Tishevsky, Aleksey V., Gurchin, Yuri V., Isupov, Aleksander Yu., Janek, Marian, Khrenov, Anatoly N., Kurilkin, Pavel K., Kushpil, Vasily, Ladygin, Vladimir P., Mezhenska, Olena, Reznikov, Sergey G., and Terekhin, Arkady A.
- Subjects
SCINTILLATION counters ,LIGHT sources ,SILICON detectors ,NUCLEAR research ,PHOTOMULTIPLIERS ,NOISE measurement ,IDEAL sources (Electric circuits) ,DETECTORS - Abstract
The paper presents measurements of the noise characteristics of silicon photomultipliers in the temperature range from 27.7 °C to 39.1 °C, as well as study of the response of the detector prototypes with Ketek and Hamamatsu SiPM readout to the light source at different voltages. The prototype with SiPM readout from Ketek was tested at the Joint Institute for Nuclear Research Nuclotron deuteron beam at the energy of 4 GeV/nucleon. Time resolution and amplitude of the signal have been estimated. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
50. Contents list.
- Subjects
ENANTIOMERIC purity ,SCINTILLATION counters ,COORDINATION polymers - Published
- 2019
- Full Text
- View/download PDF
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