@prefix dcat: . @prefix dct: . @prefix foaf: . @prefix vcard: . @prefix xsd: . a dcat:Dataset ; dct:description """ 233U is the fissile nucleus produced in 232T h/233U fuel cycle which has been proposed as asafer and cleaner alternative to the 238U/239P u cycle. The accurate knowledge of the neutroncapture cross-section of this isotope is needed with high-precision for design and developmentof this fuel cycle. The only two reliable experimental data for the capture cross-section of233U show discrepancies up to 10%. These differences may be due to systematic uncertaintiesassociated with the detector efficiency, dead-time effects, background subtraction and signalpile-up caused by the α-activity of the sample. A special experimental set-up for simultaneousmeasurement of fission and capture cross sections of radioactive fissile nuclei was designed,assembled and optimized at CENBG in the frame of this work. The measurement will be per-formed at the Gelina neutron time-of-flight facility at IRMM, where neutron cross sectionscan be measured over a wide energy range with high energy resolution. The fission detectorconsists of a multi-plate high-efficiency ionization chamber (IC). The γ-rays produced in cap-ture reactions are detected by an array of six C6 D6 scintillators surrounding the IC. In thesemeasurements the radiative capture γ-rays are hidden in large background of fission γ-rays thatrepresents a challenging issue. The latter has then to be subtracted by detecting fission eventswith a very well known efficiency (VETO method). An accurate determination of this efficiencyis rather difficult. In this work we have thoroughly investigated the prompt-fission-neutronsmethod for the IC efficiency measurement, providing new insights on this method. Thanks tothis study the IC efficiency was determined with a very low uncertainty. Using a 252Cf source,several parameters (gas pressure, high voltage and the distance between the electrodes) havebeen studied to determine the behaviour of the IC in order to find the ideal operation point:a good energy separation between α-particles and fission fragments (FF) and a good timingresolution. A good α-FF separation has been obtained with a highly radioactive 233U target.Also, the pulse-shape discrimination between γ-rays and neutrons in the C6D6 detectors wasobserved at Gelina under realistic experimental conditions. To conclude, the experimentalset-up and the VETO method have been carefully checked and validated, opening the way tofuture measurements of the capture and fission cross sections of 233U. """ ; dct:identifier "NNT: 2013BOR15224" ; dct:issued "2026-05-05T20:51:28.844812"^^xsd:dateTime ; dct:language "en" ; dct:modified "2026-05-05T20:51:28.844816"^^xsd:dateTime ; dct:publisher ; dct:title "Développement d’un dispositif expérimental dédié à la mesure des sections efficaces de capture et de fission de l’233u dans le domaine des résonances résolues" ; dcat:contactPoint [ a vcard:Organization ; vcard:fn "CCSD" ] ; dcat:distribution ; dcat:keyword "c6-d6-scintillators", "chambre-a-ionisation", "cycle-thorium", "development-of-experimental-set-up-for-neutron-and-gamma-detection", "developpement-dun-dispositif-experimental-pour-la-detection-des-neutrons-et", "eciency-measurement", "fssile-isotope", "geant4-simulations", "infoeu-reposemanticsdoctoralthesis", "ionisation-chamber", "isotope-ssile", "mesure-de-lecacite", "methode-veto", "neutron-induced-capture-and-ssion-cross-sections", "scintillateurs-c6-d6", "sduothersciences-of-the-universe-physicsother", "sections-ecaces-neutronique-de-ssion-et-de-capture", "simulations-geant4", "theses", "thorium-cycle", "veto-method" ; dcat:landingPage . a dcat:Distribution ; dct:format "HTML" ; dct:issued "2026-05-05T20:51:28.908599"^^xsd:dateTime ; dct:modified "2026-05-05T20:51:28.822883"^^xsd:dateTime ; dct:title "Développement d’un dispositif expérimental dédié à la mesure des sections efficaces de capture et de fission de l’233u dans le domaine des résonances résolues" ; dcat:accessURL . a foaf:Agent ; foaf:name "test_moissonnage_selune" . a foaf:Document .