New external beam and particle detection set-up of Liège cyclotron – First applications of high energy beams to cultural heritage

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2012), 273

Improvements on the Liége cyclotron have yielded an energy resolution comparable to that of classic electrostatic accelerators. The latest upgrades of the High-Energy High-Resolution beam line (HE-HR) are ... [more ▼]

Improvements on the Liége cyclotron have yielded an energy resolution comparable to that of classic electrostatic accelerators. The latest upgrades of the High-Energy High-Resolution beam line (HE-HR) are presented which consist of the addition of both a new extraction nozzle for non-invasive in-air measurements and a new particle-detection setup developed to take full advantage of the increased probed thickness with depth sensitive analytical methods. The suitability of the new setup and the advantages provided by the larger flexibility in choosing both the proper particle with an extended energy available will be illustrated by discussing latest results of studies recently led on Roman gilding techniques on cultural heritage artifacts by means of “High-Energy” alpha backscattering spectrometry combined with PIXE. [less ▲]

X-ray production cross-sections measurements for high-energy alpha particle beams: New dedicated set-up and first results with aluminum

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2011), 269(24), 29792983

The “IPNAS” laboratory, in collaboration with the “Centre Européen d’Archéométrie” is partly focused on material analysis by means of IBA techniques: PIXE, PIGE and RBS. A new transport beam line has been ... [more ▼]

The “IPNAS” laboratory, in collaboration with the “Centre Européen d’Archéométrie” is partly focused on material analysis by means of IBA techniques: PIXE, PIGE and RBS. A new transport beam line has been developed at our CGR-520 MeV cyclotron to analyze Cultural Heritage objects using these techniques. This facility allows us to produce proton and alpha particle beams with energies up to 20 MeV. A vacuum chamber dedicated to X-ray production and Non-Rutherford cross-section measurements has been recently constructed. After determination of the chamber’s geometry for X-ray detection using thin foils of several elements (11 ⩽ Z ⩽ 82) and 3 MeV proton beams, the measurement of the X-ray production cross-sections in the 6–12 MeV energy range has started using alpha particle beams on light element targets. These experiments contribute to the filling a serious lack of experimental values for alpha particles of this particular energy range in databases. The recent decision to focus our work on the alpha particle interaction with light elements was taken because of the high interest of the low Z elements in the field of archaeometry. [less ▲]

Combined PIXE/PIGE and IBIL with external beam applied to the analysis of Merovingian glass beads

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2010), 268(11-12), 2078-2082

New improvements on our archaeometry line at the cyclotron of the Institute of Nuclear and Atomic Physics and of Spectrometry of the University of Liege have allowed the use of PIXE/PIGE and IBIL in-air ... [more ▼]

New improvements on our archaeometry line at the cyclotron of the Institute of Nuclear and Atomic Physics and of Spectrometry of the University of Liege have allowed the use of PIXE/PIGE and IBIL in-air for the analysis of cultural heritage objects. The extraction is performed through a 100 nm thick Si3N4 window. The detection set-up consists now of two X-ray and one gamma-ray detectors, together with a fiber optic UV-visible spectrometer. This set-up has already been tested for the analysis of modern corundum [1] and is now adapted to the analysis of archaeological artefacts. In this work, we have used it to analyse 216 out of the 5000 Merovingian glass beads that come from the necropolis of Bossut-Gottechain (Belgium), one of the most important ever found in Belgium. The IBA analyses confirmed the typological division of different beads groups through chemical composition that gives us new insights on fabrication techniques of glass matrices and colorants. (C) 2010 Elsevier B.V. All rights reserved. [less ▲]

Preliminary experiments: High-energy alpha PIXE in archaeometry

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2010), 268(11-12), 1911-1915

This paper describes the work realized at the "Centre Europeen d'Archeometrie" to highlight the utility of high-energy alpha PIXE in the particular field of archaeometry and to introduce the developments ... [more ▼]

This paper describes the work realized at the "Centre Europeen d'Archeometrie" to highlight the utility of high-energy alpha PIXE in the particular field of archaeometry and to introduce the developments done and to be clone to complete the knowledge of high-energy alpha PIXE. It starts with the comparison of the yield and the noise background between several alpha particle beams and the comparison between alpha particle and proton beams on different thick and thin references. After, this paper depicts the developments done at the "Institut de Physique Nucleaire, Atomique et Spectroscopie" to perform such high-energy experiments, first on standards and later on cultural heritage objects. Moreover, it introduces the problematics of such beams for the quantification in PIXE by the intermediary of the knowledge of the ionization and X-ray production cross-sections and also the developments done to answer to this serious lack in the databases. (C) 2010 Elsevier B.V. All rights reserved. [less ▲]

Improved energy resolution of a cyclotron beam for RBS measurements

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2008), 266(10), 2110-2112

Study of the provenance of Belgian Merovingian garnets by PIXE at IPNAS cyclotron

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2008), 266(10), 2348-2352

Recent archaeological excavation in Belgium reveals one of the biggest Merovingian necropolis ever found in this country. This necropolis contains 436 tombs with a period of occupation of almost two ... [more ▼]

Recent archaeological excavation in Belgium reveals one of the biggest Merovingian necropolis ever found in this country. This necropolis contains 436 tombs with a period of occupation of almost two centuries. Some of these tombs were very rich, especially two of them, and delivered an important funerary furniture. About 60 jewels inlaid with red garnets have been found, most of them of "cloisonne" style (namely about 450 garnets). The new extracted beam set-up of the IPNAS cyclotron (University of Liege, Belgium) has been improved in order to analyse by PIXE these garnets and try to determine their provenance. These analyses reveal that the garnets found in the necropolis of Grez-Doiceau are very homogeneous in composition (almandine garnets) and are coming almost from a unique source. These results have been compared to previous studies led in France during these past five years. This permits to identify the source of almandine garnet situated in India and to highlight differences in garnet supply between France and Belgium in Merovingian times. (C) 2008 Elsevier B.V. All rights reserved. [less ▲]

Characterisation of an enamelled metallic object found in Guerrero Negro (Baja California) by PIXE and RBS techniques

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2008), 266

Relationship between IOL emission and bond-distance (M-O) in carbonates

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2006), 249

Gamma-ray attenuation for measuring cryogenic slush mixture density

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2005), 229(1), 111-116

Gamma-ray attenuation is used to measure cryogenic mixture density. Parameters are optimized for specific space application. A simple error formula is established. The feasibility of the measurement is ... [more ▼]

Gamma-ray attenuation is used to measure cryogenic mixture density. Parameters are optimized for specific space application. A simple error formula is established. The feasibility of the measurement is demonstrated. An automatic measurement device is built. (C) 2004 Elsevier B.V. All rights reserved. [less ▲]

The recognition of biological cells utilizing quantitative phase microscopy system

in Nuclear Instruments & Methods in Physics Research. Section B, Beam Interactions with Materials and Atoms (2005), 231

Single ion bombardment of biological cells using an ion microprobe is a promising technique. However, for microprobe investigations of biological processes at a cellular level the precise recognition of a ... [more ▼]

Single ion bombardment of biological cells using an ion microprobe is a promising technique. However, for microprobe investigations of biological processes at a cellular level the precise recognition of a single cell and particularly of its nucleus is required. Moreover, cells must be examined in their natural state and environment (i.e. without previously being killed, preferentially not fixed nor stained) and, also, the use of ultraviolet light for cells observation should be avoided. Additionally, in order to obtain statistically significant results of irradiation, the possibility of fast automatic recognition of thousands of objects must be provided. Because computer recognition strongly depends on the quality of an image, the optical imaging system is of crucial importance. For this purpose one of the best solutions could be the Quantitative Phase microscopy (QPm) technique. QPm is the recent digital technique of phase contrast microscopy, providing quantitative phase and intensity data obtained from a series of defocused images. The following phase contrast modalities may be generated digitally from the computed QPm phase data with a greater degree of flexibility: Pure phase images (intensity-free), standard phase contrast (e.g. Zernike phase contrast), differential interference contrast (DIC), Hoffman modulation contrast, and simulated darkfield. (c) 2005 Elsevier B.V. All rights reserved. [less ▲]