VIRTUAL Thursday, April 28th 2022 3:45 – 4:45 pm (MT) WEBEX Speaker: Peter Schillebeeckx European Commission, Joint Research Centre (JRC), Geel (Belgium) “Neutron resonance analysis and applications to material characterization ” Abstract: In this seminar the use of neutron resonance spectroscopy for the characterisation of materials and objects is discussed. The JRC Geel operates a neutron time-of-flight facility GELINA which is mainly used to produce nuclear data of interest to various disciplines in nuclear science and technology. This facility has been especially designed for high quality neutron-induced reaction cross section studies in the resonance region. It is a multi-user facility, serving up to 10 different experiments simultaneously, and providing a pulsed white neutron source, with a neutron energy range between 10 meV and 20 MeV, a time resolution of 2 ns and flight path lengths ranging from 10 m to 400m. Since 2000 this facility is also used to characterise materials and objects by neutron resonance spectroscopy. In this seminar, Neutron Resonance Analyse (NRA) as a Non-Destructive Analysis (NDA) method to determine the overall (bulk) composition of materials is discussed. This can be done by detecting prompt g-rays, which are emitted after a neutron capture reaction in the object being studied. This technique, known as Neutron Resonance Capture Analysis (NRCA), is sensitive to almost all stable nuclides and can be applied to determine the elemental and isotopic composition including trace elements and impurities. Another technique, referred to as Neutron Transmission Analysis (NRTA), is based on a measurement of the transmission of neutrons through the object. This is an absolute method that works well for the main elements present in the sample. NRCA and NRTA are used at GELINA for nuclear energy and non-energy applications. NRCA is applied at the time-of-flight facilities GELINA in collaboration with the University of Dellft (NL) to study objects and artefacts of archaeological and cultural heritage interest. The majority of the data results from measurements at the 12.5 m capture measurement station. Most of the archaeological applications so far are related to copper-alloy artefacts. Apart from Cu, they contain Sn or Zn as other major elements, and As, Ag, Sb, Co, Fe, In and Pb as minor or trace elements. At present NRTA is extensively used at GELINA as an absolute NDA technique for nuclear data validation (i.e. resonance parameters) and to characterise samples that were used as part of dedicated programs at the MINERVE reactor of the CEA Cadarache (FR). Examples of these applications will also be given. Finally, the JRC Geel contribution to a European project, entitled "Spent Fuel Characterization and Evolution Until Disposal" will be presented. Bio: P. Schillebeeckx got his PhD at the university of Ghent in 1988. The subject was the investigation of fission fragment properties. He started his professional carrier at the Institute Lau Langevin where he was scientific responsible for gamma-ray spectrometers. In 1989 he joined the EC-JRC at Ispra, where he was scientific responsible for the development of NDA measurement techniques based on active and passive neutron assay, gamma-ray spectroscopy and calorimetry. Since 2001 he is working at the JRC in Geel where he is the nuclear data group and project leader and the scientific responsible for measurements at the time-of-flight facility GELINA and at the tandem generator MONNET. He is specialised in cross section measurements and the production of covariance data in the resonance region. One of his achievements is the development of a NDA technique to determine the elemental and isotopic composition of materials based on neutron resonance analysis.