Littérature scientifique sur le sujet « HPGe spectrometry »

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Articles de revues sur le sujet "HPGe spectrometry"

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Marković, Nikola, Per Roos, Xiaolin Hou et Sven Poul Nielsen. « Calibration of HPGe–HPGe coincidence spectrometer through performing standardisation of 125 I activity by X-ray-gamma coincidence spectrometry using two HPGe detectors ». Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment 880 (février 2018) : 194–200. http://dx.doi.org/10.1016/j.nima.2017.10.086.

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Hou, Dongjie, Siming Guo, Jianwei Huang, Chong Wu et Jinjie Wu. « Monte Carlo simulation of HPGe gamma-spectrometry systems ». Journal of Engineering 2019, no 23 (1 décembre 2019) : 9064–68. http://dx.doi.org/10.1049/joe.2018.9185.

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This, Kélian, Laurent Le Brusquet, Adrien Frigerio, Sébastien Colas et Pascal Bondon. « Baseline removal in spectrometry gamma by observation of local minima ». SYSTEM THEORY, CONTROL AND COMPUTING JOURNAL 1, no 1 (30 juin 2021) : 1–12. http://dx.doi.org/10.52846/stccj.2021.1.1.4.

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This paper presents a Baseline Removal method in the context of spectrometry gamma. The method implements an estimator for the full continuum based on the observation of local minima. This estimator is constructed from the statistical properties of the signal and is therefore easily explainable. The method involves a limited number of fixed parameters, which allows the automation of the process. Moreover, the method is adaptable to any peaks width, which makes it suitable for both HPGe spectrometers and scintillators. Application to real gamma spectrometry measurements are presented, as well as a discussion about the choice of the parameters, for which an adjustment is proposed.
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Povinec, P., M. Betti, A. Jull et P. Vojtyla. « New isotope technologies in environmental physics ». Acta Physica Slovaca. Reviews and Tutorials 58, no 1 (1 février 2008) : 1–154. http://dx.doi.org/10.2478/v10155-010-0088-6.

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New isotope technologies in environmental physicsAs the levels of radionuclides observed at present in the environment are very low, high sensitive analytical systems are required for carrying out environmental investigations. We review recent progress which has been done in low-level counting techniques in both radiometrics and mass spectrometry sectors, with emphasis on underground laboratories, Monte Carlo (GEANT) simulation of background of HPGe detectors operating in various configurations, secondary ionisation mass spectrometry, and accelerator mass spectrometry. Applications of radiometrics and mass spectrometry techniques in radioecology and climate change studies are presented and discussed as well. The review should help readers in better orientation on recent developments in the field of low-level counting and spectrometry, and to advice on construction principles of underground laboratories, as well as on criteria how to choose low or high energy mass spectrometers for environmental investigations.
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Chinnaesakki, S., S. V. Bara, S. J. Sartandel, R. M. Tripathi et V. D. Puranik. « Radiological characterisation of synthetic rutile using HPGe gamma spectrometry ». Radiation Protection Dosimetry 140, no 4 (22 avril 2010) : 378–82. http://dx.doi.org/10.1093/rpd/ncq136.

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Povinec, P. P., I. Osvath et M. S. Baxter. « Underwater gamma-spectrometry with HPGe and NaI(Tl) detectors ». Applied Radiation and Isotopes 47, no 9-10 (septembre 1996) : 1127–33. http://dx.doi.org/10.1016/s0969-8043(96)00118-2.

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Khandaker, M. U., P. J. Jojo, H. A. Kassim et Y. M. Amin. « Radiometric analysis of construction materials using HPGe gamma-ray spectrometry ». Radiation Protection Dosimetry 152, no 1-3 (11 août 2012) : 33–37. http://dx.doi.org/10.1093/rpd/ncs145.

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Sajo-Bohus, L., D. Rosso, A. M. Sajo Castelli, D. R. Napoli, E. Fioretto, R. Menegazzo, H. Barros, C. A. Ur, D. Palacios et J. Liendo. « HPGe detectors long time behaviour in high-resolution γ spectrometry ». Nuclear Instruments and Methods in Physics Research Section A : Accelerators, Spectrometers, Detectors and Associated Equipment 648, no 1 (août 2011) : 132–38. http://dx.doi.org/10.1016/j.nima.2011.03.031.

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Sima, Octavian, et Dirk Arnold. « On the Monte Carlo simulation of HPGe gamma-spectrometry systems ». Applied Radiation and Isotopes 67, no 5 (mai 2009) : 701–5. http://dx.doi.org/10.1016/j.apradiso.2009.01.014.

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Foley, A., S. K. Mohanty et G. E. Sjoden. « Developing a basis for heavy metal in-situ detection using CZT ». Journal of Instrumentation 17, no 05 (1 mai 2022) : P05026. http://dx.doi.org/10.1088/1748-0221/17/05/p05026.

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Abstract Heavy metal contamination is a global concern–this type of contamination in the environment has been on the rise since the industrial age. Current guidelines from the United States Environmental Protection Agency and the World Health Organization limit arsenic concentration in water sources to 10 μg/kg. Typically, detection of heavy metals in industrial processes include spectrophotometry and colorimetry. A viable alternative for heavy metal detection can be implemented using a room temperature gamma spectrometer paired with a portable neutron generator for in-situ neutron activation analysis. In this paper, we explore detection of an arsenic salt diluted in a water sample to specific concentrations; the arsenic sample is utilized to determine the capability of a 5 mm × 5 mm × 5 mm CZT detector for heavy metal detection by neutron activation analysis. Several arsenic dilutions were irradiated in the University of Utah TRIGA reactor (UUTR), and the samples were measured on both HPGe and CZT detectors. The direct comparator method was used to determine the sample mass in a sample attributed by each detector, and the results were compared to the known dilution arsenic mass. We determined that a CZT gamma spectrometer can reliably detect 10 mg/kg arsenic with high confidence, and as low as 1 mg/kg arsenic with low confidence. For comparison, an HPGe gamma spectrometer can reliably detect 1 mg/kg arsenic with high confidence, and as low as 0.1 mg/kg with low confidence. Based upon our MDA, the CZT spectrometer can detect samples with a total activity of 1.8×10-5 mCi and higher, and the HPGe detector can detect an activity of 1.8×10-6 mCi. These results suggest the method has potential in portable gamma spectrometry solutions for wastewater effluents from industrial processes such as paint manufacturing, pharmaceutical, and smelting operations.
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Thèses sur le sujet "HPGe spectrometry"

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TAKEDA, MAURO N. « Determinacao da correcao para o efeito de soma em cascata para espectrometros de HPGe pelo metodo de Monte Carlo ». reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10916.

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Dissertacao (Mestrado)
IPEN/D
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Hernández, Suárez Francisco Javier. « Optimisation of environmental gamma spectrometry using Monte Carlo methods ». Doctoral thesis, Uppsala University, Department of Physics, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-2672.

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Dissertation in Environmental Physics to be publicly examined in Häggsalen (Ångström Laboratory), Uppsala University, on Friday, November 8, 2002 at 10:00 am for the degree of doctor of philosophy in Physics. The examination will be conducted in English.

Gamma spectrometry is one of the tools commonly used for the measurement of various environmental radionuclides. Simultaneous determination of the absolute activity of gamma emitting radiotracers in a wide range of environmental matrices and fractions necessitates proper and accurate evaluation of the sample-to-detector efficiency. Several radiotracers require, in addition, the use of sub-routines for self-absorption corrections.

Gamma spectrometry is an important and elegant tool for assessing environmental changes. Optimisation of ultra low-level gamma spectrometry for reliable assessment of such changes requires harmonisation of laboratory needs with sampling and site conditions.

Different aspects of the calculation of sample-to-detector efficiencies using empirical and Monte Carlo approaches are discussed here, including the uncertainties related to the simulation of the performance of different HPGe detectors and the effects of the incomplete collection of charges in Ge-crystals. Various simulation codes for the computation of peak efficiencies in planar and well Ge-detectors have been developed from scratch. The results of the simulations have been tested against experimental data and compared to other simulation results obtained with the Monte Carlo N-Particle code (MCNP). The construction of calibration sources with improved absorption and collimation characteristics have been, also, described in this work. These sources have been especially designed for the efficiency calibration of Ge-detectors at energies below 100 keV.

Flexible, fully tested and prototype approaches for the evaluation of self-absorption corrections, based on Monte Carlo simulations, are described. Special consideration is given to the problems related to the sample's variability in size, density and composition. Several examples of the absolute and simultaneous determination of environmental multitracers which benefited from self-absorption corrections and the optimised efficiency calibration algorithms are, also, presented and discussed. These examples include, among other things, a comprehensive analysis of the gamma spectrometry of 234Th in a wide range of matrices and the speciation of several radionuclides in sediments from a hard-water lake.

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Máduar, Marcelo Francis. « Desenvolvimento de um código computacional aberto de análise quantitativa para determinação de radionuclídeos por espectrometria gama com detectores semicondutores ». Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/85/85131/tde-12082011-150805/.

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A quantificação da atividade de radionuclídeos emissores de raios gama em amostras medidas por espectrometria gama com detectores HPGe depende da análise dos fotopicos presentes no espectro, especialmente da determinação exata das suas áreas líquidas. Tal análise é geralmente realizada com o auxílio de ferramentas de software proprietário. Este trabalho apresenta uma metodologia, descrição de algoritmos e um aplicativo de código aberto, denominado OpenGamma, para a busca e análise de fotopicos a fim de se obter seus parâmetros relevantes e as atividades dos radionuclídeos na amostra. A implementação computacional é distribuída sob licença aberta para o código principal e com o uso de pacotes de software aberto para o projeto da interface e para bibliotecas matemáticas. O procedimento para a busca de picos é realizado em três etapas. Primeiramente, executa-se uma pesquisa preliminar com o método da segunda diferença, que consiste na geração de um espectro derivado para a busca de picos candidatos. Na segunda etapa, calculam-se as larguras experimentais dos picos, dos quais escolhem-se aqueles bem formados e isolados para a obtenção da função de ajuste da largura vs. canal, por meio do método de Levenberg-Marquardt para ajustes não-lineares. Por fim, regiões do espectro com picos agrupados são delimitadas e novo ajuste não-linear é aplicado a cada região para a obtenção dos termos da linha de base e dos fotopicos. A partir destes termos, são calculadas as áreas líquidas dos picos. Para a determinação da atividade, curvas de calibração de eficiência previamente obtidas, bem como dados de transições gama dos radionuclídeos, são incorporadas ao código e aplicadas. O código foi escrito em linguagem C++ e a interface foi desenvolvida com a ferramenta Qt. Para as funções matemáticas e procedimentos de ajuste, foi usada a biblioteca científica GNU (GSL). A validação de código foi feita por meio da análise de: 1) espectros sintéticos de teste da AIEA, especialmente desenhados para a avaliação de desempenho de software; 2) espectros obtidos com amostras de exercícios de intercomparação e 3) espectros da rotina de trabalho do Laboratório de Radiometria Ambiental (LRA) do IPEN e analisados com o aplicativo comercial InterWinner. Os resultados obtidos são consistentes com os valores de referência e com aqueles obtidos pelo aplicativo citado, sugerindo que o código OpenGamma pode ser utilizado com segurança na espectrometria de raios gama de uso geral.
Radioactivity quantification of gamma-ray emitter radionuclides in samples measured by HPGe gamma-ray spectrometry relies on the analysis of the photopeaks present in the spectra, especially on the accurate determination of their net areas. Such a task is usually performed with the aid of proprietary software tools. This work presents a methodology, algorithm descriptions and an open source application, called OpenGamma, for the peak search and analysis in order to obtain the relevant peaks parameters and radionuclides activities. The computational implementation is released entirely in open-source license for the main code and with the use of open software packages for interface design and mathematical libraries. The procedure for the peak search is performed on a three step approach. Firstly a preliminary search is done by using the second-difference method, consisting in the generation of a derived spectrum in order to find candidate peaks. In the second step, the experimental peaks widths are assessed and well formed and isolated ones are chosen to obtain a FWHM vs. channel relationship, by application of the Levenberg-Marquardt minimization method for non-linear fitting. Lastly, regions of the spectrum with grouped peaks are marked and a non-linear fit is again applied to each region to obtain baseline and photopeaks terms; from these terms, peaks net areas are then assessed. For the activity determination, previously obtained efficiency calibration curves, as well as nuclides gamma-ray data, are incorporated in the code and applied. The code was developed in C++ language and the interface was developed with Qt GUI software toolkit. GNU scientific library, GSL, was employed to perform fitting procedures as needed. Validation of code was done by analyzing: 1) synthetic test spectra from IAEA, especially designed for software performance evaluation; 2) spectra obtained from samples of intercomparison exercises and 3) spectra from routine activities of the Environmental Radiometric Laboratory (LRA) at IPEN and analyzed with the commercial software package InterWinner. Results obtained are consistent with the reference values and with those obtained by the aforementioned package. The results suggest that the OpenGamma code could be safely used in general-purpose gamma-ray spectrometry.
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Mubashir, Hassan. « Installation and optimization of a gamma spectrometry system in anticoincidence ». Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.

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The work covered by this thesis was carried out at the Brasimone ENEA Research Centre, the National Agency for New Technologies, Energy and Sustainable Economic Development, with the aim of optimising a gamma spectrometry system in anticoincidence for the detection of noble gases, in particular the radioactive isotopes of xenon 131mXe, 133Xe, 133mXe and 135Xe. The laboratory of the ENEA Research Center of Brasimone, where the experimental apparatus is found to carry out the measurements of 131mXe, 133Xe, 133mXe and 135Xe, collaborates constantly with the monitoring network and is able to provide, if necessary, data and analysis on noble gases. The signals produced by the interaction of cosmic rays that manage to pass the screen have been recognized as the main cause of the increase of the detector background because they give rise to the Compton continuum and, as a result, they increase the value of detectable MDA. For this reason, a system in anticoincidence has been developed through the use of two plastic scintillators, placed over the shielding of the Hpge detector, which sends pulses recording within a gate located in the germanium multichannel analyzer: at the time the signal arrives from the scintillator, the gate blocks data acquisition to avoid recording pulses generated by cosmic radiation. For both configurations of the system, therefore, both with the anti-coincidence apparatus inactive and in operation, energy, FWHM and efficiency calibrations had to be carried out using a certified multi-peak source. The solution proposed, in conclusion of the thesis, to eliminate any electronic interference with the efficiency of the detector provides for the replacement of the current electronic apparatus with a new fully digitized, made by the company CAEN, Nuclear Electronic Construction Equipment.
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XHIXHA, Gerti. « Advanced gamma-ray spectrometry for environmental radioactivity monitoring ». Doctoral thesis, Università degli studi di Ferrara, 2012. http://hdl.handle.net/11392/2388782.

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The environmental radioactivity monitoring programs start in the late 1950s of the 20th century following the global fallout from testing of nuclear weapons in the atmosphere, becoming a cause of concern regarding health effects. Later, the necessity of world industrialization for new energy sources led to develop national plans on electricity production from nuclear technology, initializing in this context world wide exploration for fuel minerals: uranium exploration gained a particular attention in late 1940's in USA, Canada and former USSR and in 1951 in Australia with respective national plans. Nowadays there are about 440 nuclear power plants for electricity generation with about 70 more NPP under construction giving rise to the nuclear emergency preparedness of a large number of states (like Radioactivity Environmental Monitoring (REM) data bank and EUropean Radiological Data Exchange Platform (EURDEP). Furthermore, a lot of applications in the field of geosciences are related to the environmental radioactivity measurements going from geological mapping, mineral exploration, geochemical database construction to heat -flow studies. Gamma-ray spectroscopy technique is widely used when dealing with environmental radioactivity monitoring programs. The purpose of this work is to investigate the potentialities that such a technique offers in monitoring radioactivity concentration through three different interventions in laboratory, in-situ and airborne measurements. An advanced handling of gamma-ray spectrometry method is realized by improving the performances of instruments and realizing and testing dedicated equipments able to deal with practical problems of radioactivity monitoring. For each of these gamma-ray spectrometry methods are faced also the problems of calibration, designing of monitoring plans and data analyzing and processing. In the first chapter I give a general description for the common radionuclides present in the environment having a particular interest for monitoring programs. Three categories of environmental radionuclides classified according to their origin as cosmogenic, primordial and man-made are discussed. The cosmic rays continuously produce radionulides and also direct radiation, principally high energetic muons. Cosmogenic radionuclides are originated from the interaction of cosmic rays with stable nuclides present in the Earth’s atmosphere. Primordial radionuclides are associated with the phenomenon of nucleosynthesis of the stars and are present in the Earth’s crust. Man-made radionuclides commonly present in natural environments are principally derived from radioactive fallout from atmospheric nuclear weapons testing and peaceful applications of nuclear technology like nuclear power plants for electricity generation and the associated nuclear fuel cycle facilities. A relevant contribution, generally with local implication comes from the so called non-nuclear industries which are responsible for technologically enhancement of natural radioelements producing huge amounts of naturally occurring radioactive materials (NORM/TENORM). In the second chapter is described a homemade approach to the solution of the problem rising in monitoring situations in which a high number of samples is to be measured through gamma-ray spectrometry with HPGe detectors. Indeed, in such cases the costs sustaining the manpower involved in such programs becomes relevant to the laboratory budget and sometimes becomes a limitation of their capacities. Manufacturers like ORTEC® and CANBERRA produce gamma-ray spectrometers supported by special automatic sample changers which can process some tens of samples without any human attendance. However, more improvements can be done to such systems in shielding design and detection efficiency. We developed a fully automated gamma-ray spectrometer system using two coupled HPGe detectors, which is a well known method used to increase the detection efficiency. An alternative approach on shielding design and sample changer automation was realized. The utilization of two coupled HPGe detectors permits to achieve good statistical accuracies in shorter time, which contributes in drastically reducing costs and man power involved. A detailed description of the characterization of absolute full-energy peak efficiency of such instrument is reported here. Finally, the gamma-ray spectrometry system, called MCA_Rad, was used to characterize the natural radioactivity concentration of bed-rocks in Tuscany Region, Italy. More than 800 samples are measured and reported here together with the potential radioactivity concentration map of bed rocks in Tuscany Region. In the third chapter is described the application of portable scintillation gamma -ray spectrometers for in-situ monitoring programs focusing on the problems of calibration and spectrum analysis method. In-situ γ-ray spectrometry with sodium iodide scintillators is a well developed and consolidated method for radioactive survey. Conventionally, a series of self-constructed calibration pads prevalently enriched with one of the radioelements is used to calibrate this portable instrument. This method was further developed by introducing the stripping (or window analysis) described in International Atomic Energy Agency (IAEA) guidelines as a standard methods for natural radioelement exploration and mapping. We realized a portable instrument using scintillation gamma-ray spectrometers with sodium iodide detector. An alternative calibration method using instead well-characterized natural sites, which show a prevalent concentration of one of the radioelements, is developed. This procedure supported by further development of the full spectrum analysis (FSA) method implemented in the non-negative least square (NNLS) constrain was applied for the first time in the calibration and in the spectrum analysis. This new approach permits to avoid artifacts and non physical results in the FSA analysis related with the χ2 minimization process. It also reduces the statistical uncertainty, by minimizing time and costs, and allows to easily analyze more radioisotopes other than the natural ones. Indeed, as an example of the potentialities of such a method 137Cs isotopes has been implemented in the analysis. Finally, this method has been tested by acquiring gamma Ombrone -ray spectra using a 10.16 cm×10.16 cm sodium iodide detector in 80 different sites in the basin, in Tuscany. The results from the FSA method with NNLS constrain have been compared with the laboratory measurements by using HPGe detectors on soil samples collected. In the forth chapter is discussed the self-construction of an airborne gamma-ray spectrometer, AGRS_16.0L. Airborne gamma-ray spectrometry (AGRS) method is widely considered as an important tool for mapping environmental radioactivity both for geosciences studies and for purposes of radiological emergency response in potentially contaminated sites. Indeed, they have been used in several countries since the second half of the twentieth century, like USA and Canada, Australia, Russia, Checz Republic, and Switzerland. We applied the calibration method described in the previous chapter using well -characterized natural sites and implemented for the first time in radiometric data analysis FSA analysis method with NNLS constrain. This method permits to decrease the statistical uncertainty and consequently reduce the minimum acquisition time (which depend also on AGRS system and on the flight parameters), by increasing in this way the spatial resolution. Finally, the AGRS_16.0L was used for radioelement mapping survey over Elba Island. It is well known that the natural radioactivity is strictly connected to the geological structure of the bedrocks and this information has been taken into account for the analysis and maps construction. A multivariate analysis approach was considered in the geostatistical interpolation of radiometric data, by putting them in relation with the geology though the Collocated Cokriging (CCoK) interpolator. Finally, the potential radioelement maps of potassium, uranium and thorium are constructed for Elba Island.
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Boson, Jonas. « Improving accuracy of in situ gamma-ray spectrometry ». Doctoral thesis, Umeå : Umeå University, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-1805.

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BARRESI, ANDREA. « Development of innovative techniques for ultra-trace elements analysis ». Doctoral thesis, Università degli Studi di Milano-Bicocca, 2023. https://hdl.handle.net/10281/403458.

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L'esperimento JUNO è stato proposto con l'obiettivo principale di risolvere il problema relativo all'ordinamento di massa dei neutrini attraverso misure accurate del flusso di antineutrini prodotto da reattori nucleari. A causa della sezione estremamente ridotta dei neutrini, il numero di eventi segnale previsti è molto piccolo, circa 60 eventi IBD al giorno, ed è quindi essenziale tenere sotto controllo il tasso di eventi di fondo. Ciò può essere ottenuto minimizzando tutte le sorgenti che contribuiscono alla produzione di eventi spuri e in primo luogo quelle generate dal fondo radioattivo. Per ogni capostipite delle catene naturali (U238 e Th232), per il 40K, e per alcuni nuclidi chiave, come 60Co e 210Pb, è necessario imporre forti limiti alla concentrazione che può essere presente all'interno dei materiali del rivelatore. Data la struttura del rivelatore JUNO, il materiale più critico è il liquido scintillante per il quale sono richieste concentrazioni di uranio e torio inferiori a 1E-15 g/g e potassio inferiori a 1E-16 g/g. In questa tesi, presento il lavoro che ho svolto in questo contesto con due scopi principali. Il primo è la validazione del software Monte Carlo dell'esperimento JUNO applicato alle simulazioni di fondo con l'obiettivo di verificare i limiti di radiopurezza imposti per i materiali e determinare il background-budget dell'esperimento. La seconda è l'implementazione di una tecnica di misura che permette di raggiungere le sensibilità richieste per la misura del contenuto di uranio, torio e potassio nel liquido scintillante. La validazione del software Monte Carlo dell'esperimento JUNO (SNiPER) è stata effettuata confrontandone i risultati con quelli di altri due codici di simulazione, in particolare con il software Arby, sviluppato presso l'Università degli studi di Milano-Bicocca. Ho potuto studiare diversi aspetti e molte criticità della simulazione del fondo e dei risultati riportati dallo strumento ufficiale, come l'applicazione del quenching factor e la forma degli spettri beta. Gli spettri dell'energia depositata prodotta dalle contaminazioni nei componenti principali del rivelatore JUNO sono stati calcolati con i codici Monte Carlo. Il tasso di eventi indotti nel rivelatore è stato valutato in base ai limiti di radiopurezza imposti, ottenendo il rate totale di eventi di fondo previsto. Il valore ottenuto è inferiore al limite imposto per garantire la sensibilità finale dell'esperimento. Ciò ha consentito di correggere e validare la risposta del software ufficiale dell'esperimento JUNO e di verificare l'attualità dei limiti di radiopurezza inizialmente definiti per i componenti del rivelatore. Durante il mio dottorato di ricerca ho completato lo sviluppo del nuovo sistema di misura, chiamato GeSparK che sfrutta la coincidenza tra uno scintillatore liquido e un rivelatore HPGe per ridurre il fondo del rivelatore HPGe singolo. È stata anche sviluppata una nuova tecnica di coincidenza ritardata che sfrutta la struttura nucleare del 239Np, il prodotto di attivazione del 238U, al fine di ottenere un marcatore estremamente forte di questo particolare decadimento e aumentare significativamente la sensibilità di misura rispetto all'approccio tradizionale. La sensibilità ottenuta era ancora insufficiente rispetto alle richieste di JUNO e per questo si decise di attuare una serie di trattamenti radiochimici. Diversi trattamenti sono stati proposti, testati e implementati con i due obiettivi di aumentare la massa del campione misurabile e ridurre la concentrazione di nuclidi interferenti. La tecnica sviluppata per uranio e torio prevede una fase di estrazione liquido-liquido e di estrazione cromatografia con resine UTEVA e TEVA rispettivamente prima e dopo l’irraggiamento. Due misurazioni condotte su campioni "bianchi" con la procedura finale hanno permesso di ottenere una sensibilità compatibile con i limiti imposti da JUNO per lo scintillatore liquido a livello del ppq.
The JUNO experiment was proposed with the main aim of solving the problem related to the neutrino mass ordering through accurate measurements of the antineutrinos flow produced by nuclear reactors. Due to the extremely small cross-section of neutrinos, the number of expected signal events is very small, about 60 IBD events per day, and it is therefore essential to keep under control the rate of background events. This can be achieved by minimizing all the sources that contribute to the generation of spurious events and in the first place those generated by the radioactive background. For each progenitor of the natural chains (U238 and Th232), for the 40K, and for some key nuclides, such as 60Co and 210Pb, it is necessary to impose strong limits on the concentration that may be present within the materials of the detector. Given the structure of the JUNO detector, the most critical material is the liquid scintillator for which uranium and thorium concentrations below 1E-15 g/g and potassium below 1E-16 g/g are required. In this thesis, I present the work I did in this context with two main purposes. The first one is the validation of the Monte Carlo software of the JUNO experiment applied to the background simulations with the aim of verifying the radiopurity limits imposed for the materials and determining the background budget of the experiment. The second one is the implementation of a measurement technique that allows reaching the sensitivities required for the measurement of the content of uranium, thorium, and potassium in the liquid scintillator. The validation of the Monte Carlo software of the JUNO experiment (SNiPER) was performed by comparing its results with those of two other simulation codes, in particular with the software Arby, developed at the University of Milano-Bicocca. I was able to study different aspects and many critical issues of the simulation of the background and the results reported by the official tool, such as the application of the quenching factor and the shape of the radioactive β-decay spectra. The spectra of the deposited energy produced by the contaminations in the main components of the JUNO detector were computed with the Monte Carlo codes. The rate of events induced in the detector was assessed based on the imposed radiopurity limits, obtaining the expected total background event rate. The value obtained is lower than the limit set to ensure the final sensitivity of the experiment. This allowed correcting and validating the answer of the official software of the JUNO experiment and verifying the actuality of the radiopurity limits initially defined for the components of the detector. During my Ph.D. I completed the development of the new measurement system, called GeSparK that exploits the coincidence between a liquid scintillator and an HPGe detector to reduce the background of the single HPGe detector. I also worked on the development of a new delayed coincidence technique that exploits the nuclear structure of 239Np, the activation product of 238U, in order to obtain an extremely strong marker of this particular decay and significantly increase the measurement sensitivity compared to the traditional approach. The sensitivity obtained was still insufficient compared to the requests of JUNO and for this reason, it was decided to implement a series of radiochemical treatments. Different treatments have been proposed, tested, and implemented with the two aims of increasing the mass of the measurable sample and reducing the concentration of interfering nuclides. The technique developed for uranium and thorium involves a liquid-liquid extraction phase and the extraction chromatography with UTEVA and TEVA resins respectively before and after irradiation. Two measurements conducted on "blank samples” with the final procedure allowed us to achieve a sensitivity that is compatible with the limits imposed by JUNO for the liquid scintillator at the ppq level.
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Neddermann, Till [Verfasser], Claus [Akademischer Betreuer] Gößling et Kai [Gutachter] Zuber. « Material screening by means of low-level gamma ray spectrometry with the Dortmund Low Background HPGe Facility / Till Neddermann. Betreuer : Claus Gößling. Gutachter : Kai Zuber ». Dortmund : Universitätsbibliothek Dortmund, 2014. http://d-nb.info/1106257510/34.

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SHYTI, Manjola. « Calibration and performances of in-situ gamma ray spectrometer ». Doctoral thesis, Università degli studi di Ferrara, 2013. http://hdl.handle.net/11392/2388864.

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Since 1896, when Henri Becquerel discovered that penetrating radiation was given off in the radioactive decay of uranium, the studies on radioactivity have been an interest of scientific world. With the spread of nuclear technologies applied to energy, health and industrial production, the theme of environmental radioactivity monitoring increasingly is becoming important to the policies of the health public protection both national and European level. Italy is required to comply with the recommendation of the European Commission of 8 June 2000 on the application of Article 36 of the Euratom Treaty concerning the monitoring of levels of radioactivity in the environment for the purpose of assessing the exposure of the population as a whole. In addition, the World Health Organization has identified the first group of carcinogens gas 222Rn, which is considered the second leading cause, after smoking, of lung tumors. In our environment there are various sources of radioactivity that can be natural or artificial origin. Gamma-ray spectrometry is a widely used and powerful method that can be employed both to identify and quantify radionuclides. The purpose of this work is calibration and performances of in situ a portable gamma ray spectrometer. In the first chapter I have given the necessary concepts for understanding the phenomenon of radioactivity. Qualitatively has been described the process of radioactive decay and its three types which can occur in nature. Three categories of environmental radionuclides, cosmogenic, primordial and man-made are discussed. We are exposed to environmental radiation from different sources. The origin of radioactivity in the environment can be divided into two main sources: (a) natural and (b) man-made sources. Mostly the naturally occurring radiation arises from terrestrial radioactive nuclides that are widely distributed in the earth’s crust and extra-terrestrial sources arising from cosmic ray. Also from human activities arise some other sources concerned with the use of radiation and radioactive materials from which releases of radionuclides into the environment may occur. In the second chapter is described the gamma radiation interacts with matter via three main processes: the photoelectric effect, Compton scattering and pair production The operation of a detector is based on the interaction of photons constituting the incident radiation with the material that constitutes the detector itself.. Thanks to these processes, all or part of the energy possessed by the radiation is transferred to the mass of the detector and then converted into an electrical signal. The basic notions related to the interaction of electromagnetic radiation with matter that we will provide in this chapter will therefore be useful to understand the mechanisms that are at the basis of the generation of a gamma spectrum. In addition, this chapter will briefly describe the two main types of gamma radiation detectors, i.e. the semiconductor detector and the scintillation, in particular the high-pure germanium detector (HPGe) and a sodium iodide detector activated by thallium NaI(Tl). In the third chapter is described the study area in which are performed the measurements of natural radioactivity. The area under consideration is the Ombrone basin located in southern Tuscany and Commune of Schio located in Region of Veneto. During the campaign were acquired in situ 338 spectra, including 80 with the ZaNaI_1.0L placed on the ground (Ombrone), 80 with the ZaNaI_1.0L placed on a tripod at 1m height (Ombrone), 89 with the ZaNaI_1.0L placed on the ground (Schio) and 89 spectra are acquired with a backpack placed on the shoulders of an operator (Schio). In each of the 80 sites which have been realized the measurements of radioactivity with the ZaNaI_1.0L instrument, also have been taken 5 different soil samples, for a total of 400 samples. The abundances of 40K, 238U and 232Th were obtained from the analysis of 338 spectra taken with the ZaNaI_1.0L and 400 spectra measured on soil samples in the laboratory with a high-pure germanium detector (MCA_Rad). Also it is described the procedures of ZaNaI_1.0L portable scintillation gamma-ray spectrometers for in-situ measurements. In the fourth chapter is described the procedure for the preparation of soil samples to be analyzed with the MCA_Rad system. The gamma-ray spectrometry system, called MCA_Rad introduces an innovative configuration of a laboratory high-resolution gamma-ray spectrometer featured with a complete automation measurement process, which can conduct measurements on each type of material (solid, liquid or gaseous) in less than 1 hour. The utilization of two coupled HPGe detectors permits to achieve good statistical accuracies in shorter time, which contributes in drastically reducing costs and man power involved. It is made a description of the characterization of absolute full-energy peak efficiency of such instrument reported here. In the fifth chapter are discussed the correlations between the abundances of 40K, 238U and 232Th measured with the ZaNaI_1.0L and those obtained from laboratory analysis on soil samples. The analysis was focused in particular on the study of four different types of correlation: correlation between in-situ acquisition on ground and laboratory measurements, correlation between in-situ acquisition on tripod and laboratory measurements, correlation between in-situ acquisition on ground and on tripod and correlation between in-situ acquisition on ground and on operator shoulder and the influence of vegetative cover during measurements in-situ.
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Jovana, Knežević. « Коинцидентне методе за анализу временских карактеристика нуклеарних процеса ». Phd thesis, Univerzitet u Novom Sadu, Prirodno-matematički fakultet u Novom Sadu, 2020. https://www.cris.uns.ac.rs/record.jsf?recordId=114886&source=NDLTD&language=en.

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У докторској дисертацији  приказани су резултати развијених и примењених коинцидентних метода за временску анализу нуклеарних процеса. Експериментални коинцидентни системи засновани су на  HPGe  и пластичним сцинтилационим детекторима.  Извршена су три експеримента, која су показала примењивост развијених коинцидентних система. Први део експерименталног дела обухвата анализе временских варијација интензитета космичког зрачења посредством нискоенергијских фотона. Показано је да се праћењем интензитета нискоенергијских фотона у току времена у различитим енергијским регионима остварује бољи увид у анализу фонских догађаја, стварајући предуслове за извођење експеримената који трагају за ретким нуклеарним процесима. Поред праћења временских варијација интензитета, метода се може применити и  на детекцију периодичних и апериодичних догађаја повезаних са активношћу Сунца. Други део дисертације обухватао је истраживања везана  за  детекцију потенцијалних  флуктуација константе распада 22 Na. Развијен је коинцидентни систем  и  у току времена је  праћен интензитет анихилационе линије, која је резултат анихилације позитрона емитованог распадом 22Na.  За време трајања  аквизиције података, нису пронађена значајна одступања испитиване константе распада од стандардног експоненцијалног закона радиоактивног распада. У трећем делу експерименталног рада, приказана је коинцидентна метода за временско раздвајање догађаја индукованих мионима и неутронима у околини детекторског система. Добијена је временска крива у експерименту и извршена је детаљна анализа различитих временских региона. Извршене су Монте Карло симулације, на основу којих је добијена временска крива. Анализом различитих региона симулиране временске криве, показано је да се ови догађаји могу раздвојити у две велике групе–брзе и споре догађаје. Међу спорим догађајима, показано је да се може направити разлика између догађаја индукованих мионима, међу којима доминира анихилација, и догађаја индукованих неутронима, који спадају у закаснеле догађаје у групи спорих догађаја. Добијено је да неутрони највише доприносе нискоенергијском региону, првенствено у региону до  ≈50  keV,  што их чини  нежељеном кариком фонских догађаја у експериментима који трагају за ретким нуклеарним догађајима. На основу резултата симулација, анализирани су електромагнетни и хадронски процеси индуковани мионима и неутронима, као и удели мионске и неутронске компоненте у коинцидентном спектру HPGe  детектора и директном спектру пластичног сцинтилационог детектора. Закључено је да нискоенергијском спектру,  који је превасходно значајан за ретке нуклеарне процесе,  доминантно доприносе неутрони.
U doktorskoj disertaciji  prikazani su rezultati razvijenih i primenjenih koincidentnih metoda za vremensku analizu nuklearnih procesa. Eksperimentalni koincidentni sistemi zasnovani su na  HPGe  i plastičnim scintilacionim detektorima.  Izvršena su tri eksperimenta, koja su pokazala primenjivost razvijenih koincidentnih sistema. Prvi deo eksperimentalnog dela obuhvata analize vremenskih varijacija intenziteta kosmičkog zračenja posredstvom niskoenergijskih fotona. Pokazano je da se praćenjem intenziteta niskoenergijskih fotona u toku vremena u različitim energijskim regionima ostvaruje bolji uvid u analizu fonskih događaja, stvarajući preduslove za izvođenje eksperimenata koji tragaju za retkim nuklearnim procesima. Pored praćenja vremenskih varijacija intenziteta, metoda se može primeniti i  na detekciju periodičnih i aperiodičnih događaja povezanih sa aktivnošću Sunca. Drugi deo disertacije obuhvatao je istraživanja vezana  za  detekciju potencijalnih  fluktuacija konstante raspada 22 Na. Razvijen je koincidentni sistem  i  u toku vremena je  praćen intenzitet anihilacione linije, koja je rezultat anihilacije pozitrona emitovanog raspadom 22Na.  Za vreme trajanja  akvizicije podataka, nisu pronađena značajna odstupanja ispitivane konstante raspada od standardnog eksponencijalnog zakona radioaktivnog raspada. U trećem delu eksperimentalnog rada, prikazana je koincidentna metoda za vremensko razdvajanje događaja indukovanih mionima i neutronima u okolini detektorskog sistema. Dobijena je vremenska kriva u eksperimentu i izvršena je detaljna analiza različitih vremenskih regiona. Izvršene su Monte Karlo simulacije, na osnovu kojih je dobijena vremenska kriva. Analizom različitih regiona simulirane vremenske krive, pokazano je da se ovi događaji mogu razdvojiti u dve velike grupe–brze i spore događaje. Među sporim događajima, pokazano je da se može napraviti razlika između događaja indukovanih mionima, među kojima dominira anihilacija, i događaja indukovanih neutronima, koji spadaju u zakasnele događaje u grupi sporih događaja. Dobijeno je da neutroni najviše doprinose niskoenergijskom regionu, prvenstveno u regionu do  ≈50  keV,  što ih čini  neželjenom karikom fonskih događaja u eksperimentima koji tragaju za retkim nuklearnim događajima. Na osnovu rezultata simulacija, analizirani su elektromagnetni i hadronski procesi indukovani mionima i neutronima, kao i udeli mionske i neutronske komponente u koincidentnom spektru HPGe  detektora i direktnom spektru plastičnog scintilacionog detektora. Zaključeno je da niskoenergijskom spektru,  koji je prevashodno značajan za retke nuklearne procese,  dominantno doprinose neutroni.
In  this  doctoral  thesis,  the  results  of  the  developed and  applied  coincidence   methods  on  the  timeanalysis  of  nuclear  processes  are  presented. Coincidence systems, used in presented experiments, are  based  on  the  HPGe  and  plastic  scintillation detectors.  Three  experiments  were  performed,showing  a  wide  application  of  the  developed coincidence  systems.  The  first  part  of  the experimental work involves the analysis of the time  variations of cosmic rays via low-energy photons. It was  shown  that  by  analyzing  the  intensity  of  lowenergy photons better insight into the behavior of thebackground  events  is  provided,  which  is   especially important  as  a  precondition  for  rare  nuclear  events experiments.  Furthermore,  it  was  shown  that  this method can be applied in order to search for periodic or aperiodic events resulting from the Sun activity. The  second  part  contains  the  research  of  the  22Na decay constant fluctuations. The coincidence system was  developed  and  the  intensity  of  the  annihilation line,  resulting  from  annihilation  of  the  positrons emitted from 22Na, was followed with time. During  he  acquisition  time,  no  significant  deviations  from the standard exponential radioactive decay law were found. In  the  third  part  of  the  experimental  work,  the coincidence  method  for  time  separation  of  the events,  induced  by  cosmic  muons  and  neutrons  in the  vicinity  of  the  detectors  system,  was  presented. The time curve was obtained in the experiment and the  detailed  analysis  of  the  different  time  regions was  performed.  The  Monte  Carlo  simulations  were conducted  and  the  time  curve  from  the  simulation results was obtained. Analyzing the different regions of the simulated time curve, it was noticed that these events can be separated into two groups–prompt and delayed.  Between  delayed  events,  it  was  concluded that  events  induced  by  muons,  dominantly annihilation  line,  and  events  induced  by  neutrons, which  may  be  classified  as  more  delayed  events  in the  group  of  the  delayed  events,  can  be distinguished.  It  was  concluded  the  neutrons dominantly  contribute  to  the  low-energy  region, mostly  in  the  region  to  ≈50  keV,  which  makes neutrons  an  important  background  in  the experiments searching for rare nuclear events. Based on  the  simulation  results,  electromagnetic  and hadronic processes induced by muons and neutrons, as  well  as  portions  of  muon’s  and  neutron’s component  in  the  coincidence  spectrum  of  HPGe detector  and  direct  spectrum  of  the  plastic scintillation  detector  were  analyzed.  It  was concluded  that  in  the  low-energy  part  of  the spectrum,  primarily important for the search for rare nuclear  events,  dominant  influence  is  originated from cosmic neutrons.
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Chapitres de livres sur le sujet "HPGe spectrometry"

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D'Alberti, F., et M. Forte. « Calibration of a HPGe detector for in-situ gamma spectrometry : a comparison between a Monte Carlo based code and an experimental method ». Dans Radioactivity in the Environment, 198–206. Elsevier, 2005. http://dx.doi.org/10.1016/s1569-4860(04)07022-6.

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Actes de conférences sur le sujet "HPGe spectrometry"

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Cheng, Zhiwei. « Gamma Spectrometry Measurement for the Soil in Contaminated Fields ». Dans ASME 2001 8th International Conference on Radioactive Waste Management and Environmental Remediation. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/icem2001-1144.

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Abstract This paper introduces a method of HPGe gamma spectrometry measurement for the soil samples collected from contaminated fields. HPGe gamma spectrometry system is equipped in a transportable laboratory, and the samples can be processed and analyzed on-site.
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Barat, Eric, Thomas Dautremer, Laurent Laribiere, Jean Lefevre, Thierry Montagu et Jean-Christophe Trama. « ADONIS : a new system for high count rate HPGe &#x003B3 ; spectrometry ». Dans 2006 IEEE Nuclear Science Symposium Conference Record. IEEE, 2006. http://dx.doi.org/10.1109/nssmic.2006.356004.

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Adsley, Ian, Michael Green, Ian Pearman et Michael Davies. « Assay of Plutonium Contaminated Waste by Gamma Spectrometry ». Dans ASME 2011 14th International Conference on Environmental Remediation and Radioactive Waste Management. ASMEDC, 2011. http://dx.doi.org/10.1115/icem2011-59039.

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This paper considers the use of two types of gamma detector for the in-situ assay of plutonium contaminated materials (PCM): the thin sodium iodide FIDLER (Field Instrument for the Detection of Low Energy Radiation) and the HPGe (High Purity Germanium) detector. The difficulty of the accurate assay of PCM in the past has led to a default mechanism of collecting such wastes in drums, or other types of containers, for subsequent assessment. This has resulted in many thousands of such drums being collected and stored on the major UK sites which were involved with the handling and processing of plutonium. In some cases these drums have been stored for over 20 years. This paper gives a description of the current technologies for monitoring these stored wastes, but more importantly proposes that it would be a better practice to measure such future PCM wastes in-situ, before any demolition or decommissioning is undertaken.
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Liu, Huilan, Yushou Song, Zhaoyang Xie et Baodong Sun. « The Simulation of Low-Background Gamma Spectrometer With Clover Detector ». Dans 2013 21st International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/icone21-15073.

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A low-background gamma spectrometer consists of a high-performance gamma detector and a low-background chamber. It is widely used to monitor the radiation level of the environment and to identify the species of the radiological source. It is especially important for the analysis of the nuclear accident. Usually a high purity Germanium detector (HPGe) is used as a gamma ray detector. In order to enhance the detecting accuracy and sensitivity, it is essential to improve the performance of the gamma detector. In recent years, a clover detector composed of four coaxial HPGe crystals appear and is widely utilized in nuclear physics experimental research. Because of the larger dimensions and segmented structure, it displays outstanding characteristics different from traditional HPGe detectors. With a clover detector as the main detector and the HPLBS1 chamber of ORTEC as the lead chamber, the low-background gamma spectrometer is simulated by the Monte Carlo toolkit GEANT4, where the interaction processes of gamma ray provided by the GEANT4 physics list is used. The detecting performance of the low-background gamma spectrometer such as detecting efficiency and peak-total ratio are given. The results indicate that low-background gamma spectrometer with a clover as the main detector has better characteristic than that with HPGe as a main detector traditionally.
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Rukhadze, Ekaterina, OBELIX Collaboration, TGV Collaboration et SuperNEMO Collaboration. « Low background HPGe spectrometer in investigations of 2β decay ». Dans LOW RADIOACTIVITY TECHNIQUES 2013 (LRT 2013) : Proceedings of the IV International Workshop in Low Radioactivity Techniques. AIP, 2013. http://dx.doi.org/10.1063/1.4818070.

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Rukhadze, Ekaterina, OBELIX Collaboration et SuperNEMO collaboration. « Investigations of 2β decay measured by low background HPGe spectrometer OBELIX ». Dans THE 2013 UKM FST POSTGRADUATE COLLOQUIUM : Proceedings of the Universiti Kebangsaan Malaysia, Faculty of Science and Technology 2013 Postgraduate Colloquium. AIP Publishing LLC, 2013. http://dx.doi.org/10.1063/1.4856555.

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Sun, Zhongtao, Yaopeng Zhang, Dong Zhang et Jian Song. « Modeling and Simulation of Influence Factors Measured by HPGe$\gamma$ spectrometer ». Dans 2020 IEEE International Conference on Information Technology,Big Data and Artificial Intelligence (ICIBA). IEEE, 2020. http://dx.doi.org/10.1109/iciba50161.2020.9276766.

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Mao, Cui, Yibao Liu, Liguo Zhang, Jiejuan Tong, Bing Xia et Zaizhe Yin. « Simulation of HTR-10 Anti-Compton HPGE Gamma-Ray Spectrometer With Geant4 ». Dans 2018 26th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/icone26-81254.

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The efficient and accurate burn-up measurement of the spherical fuel element is the key component of the operation of the pebble bed high temperature gas-cooled reactor. The accuracy of the method that determine burnup by the activity of Cs-137 degrades due to operation characteristics of HTR-10. HTR-10, as an test reactor, operated on and off during the past years. It stayed shutdown more than power operation. In order to improve the measurement accuracy of Cs-137 activity and enhance the possibility to detect radionuclides with low activity, which can be used to correct the classic burnup assay method, a new measurement system is now discussed using anti-coincidence technology, which suppresses the Compton plateau. In this paper, Geant4 is used to simulate the anticoincidence measurement process taking high purity germanium γ-ray spectrometer as main detector and plastic scintillator as the annular detector. By analyzing the signal to noise ratio in different detection scenarios with all kinds of shape parameters of the annular detector, the annular detector with the best anti-coincidence effect are optimaized. The above research results provide an important theoretical basis for the construction of online burn-up measurement system based on anti-Compton technology.
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Rukhadze, E., V. Brudanin, L. Fajt, R. Hodák, A. Klimenko, O. Kochetov, P. Loaiza et al. « Investigations of 2β decay of 106Cd and 58Ni with HPGe spectrometer OBELIX ». Dans LOW RADIOACTIVITY TECHNIQUES 2015 (LRT 2015) : Proceedings of the 5th International Workshop in Low Radioactivity Techniques. AIP Publishing LLC, 2015. http://dx.doi.org/10.1063/1.4928015.

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Yitang, Liu, Shi Rui, Wang Zhou, Wang Zhenchuan, Lan Yunliang, Zhao Wei et Tuo Xianguo. « Software of Radioactivity Measurement and Control System for Barreled Nuclear Waste With Segmented Gamma Scanning ». Dans 2022 29th International Conference on Nuclear Engineering. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/icone29-93603.

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Abstract Segmented Gamma Scanning (SGS) is a kind of nondestructive testing (NDT) techniques, widely used in online detection for nuclear waste drums to record the types and contents of radionuclides in the nuclear wastes. It is convenient to classify and dispose of nuclear waste according to the test results, and it also avoids radiation damage to inspectors from the destructive analysis. A new software of the radioactive analysis and monitoring system for nuclear waste barrels with SGS was developed in this work, which is mainly composed of two parts including control upper computer software and radionuclide analysis software, in which control software contained motion control and Multi-channel Analyzer (MCA) control. The controlling of the mechanical platform realized the rotation of the waste drums and the synchronous lifting and lowering of the transmission source and the detector, so as to facilitate the layered scanning of the drums. The motion control is an indispensable part of the detection system, whose precision of the movement is directly affected the accuracy of the detection results. In the radioactive measurement, a high purity germanium (HPGe) gamma-ray spectrometer was used to obtain the gamma-ray spectrum, in which the MCA was responsible for the control of spectrometer and gamma-ray spectrum data record. Therefore, the MCA control part must adjust the high voltage of the HPGe and the parameters of measurement. The gamma-ray spectrum contained the radioactive information of the nuclear wastes in the drums. The analysis of the radioactive data is the core of the software, including spectrum data resolving and the radioactive reconstructed of the radionuclides in the drums. Finally, the information such as the type and activity of the radionuclides in the barrels was provided to the user. The software was written with the C# programming language, which realized the accurate control and operation of the mechanical device and the orderly performed of motion detection. To establish communication, the software used Ethernet’s TCP/IP as the control network, in which the manual mode and auto mode were alternatives. In conclusion, the software promotes the coordination and integration of motion control, MCA control and gamma-ray spectrum data analysis in the process of automatic detection of barreled nuclear waste with SGS.
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