Ion Beams in Art and Archaeology Beam Facilities

PHYSICS AND SOCIETY 229 COST Gl Participating Laboratories Underlined are the groups which are working with ion- Ion Beams in Art and Archaeology beam facilities. Collaborations also exist with experts based outside Europe (Delaware, USA; Lower Hutt, New G. Demortier from the Laboratoire d'Analyses par Réactions Nucléaire (LARN), Namur, who Zealand; Faure, South Africa; Lucas Heights, Australia). chairs the COST Action G1 (Ion-Beam Analysis Applied to Art and Archaeology) summarises the AUSTRIA advantages of using accelerator-based techniques to study artifacts. Vienna: Akademie der Bildenden Kunste BELGIUM Namur: LARN, Facultés Universitaires ND de la Paix Antwerp: MITAC, Universitaire Instellingen The application of analytical tech cooperative COST action called Ion Beam Liège: Université niques - initially developed in the field of Analysis Applied to Art and Archaeology. A FINLAND Helsinki: Helsingin Teknillinen Oppilaitos materials science - to art or archeological memorandum of understanding for a Helsinki: Finnish National Gallery objects gives the historian and the archae COST Action was signed in June 1994, and FRANCE ologist quantitative information. This the concerted scientific activities started Paris: Laboratoire de Recherche des Musées de France helps them understand the way of life in in January 1995. The goals were as follows: Orléans: Centre Ernest Babelon, CNRS the cultures they are studying, or the tech • The development of non-destructive GERMANY Dresden: Forschungszentrum Rossendörf nical and intellectual know-how of the art nuclear and atomic methods for studying Berlin: Hahn-Meitner-Institut ists or craftsmen of the period under con items of art and archaeology using particle GREECE sideration. In the world of musea, this irradiation. Athens: NCSR Demokritos knowledge is also needed for preparing • The comparison of these novel tech HUNGARY Debrecen: ATOMKI and carrying out essential restorations, niques with conventional methods already Budapest: KFKI Institute for Particle and Nuclear Physics and for assessing the authenticity of arte used in museum laboratories for examin ITALY facts and paintings proposed for acquisi ing objects of art. Arcetri-Firenze: Università degli Studi tion. Furthermore, our entire cultural her • The creation of an interdisciplinary Venice: Università degli Studi itage is more or less doomed to disappear forum of scientists involved in archaeol ROMANIA Bucharest: Institute of Atomic Physics owing to ageing and the deleterious effects ogy and archaemetry. SLOVENIA of pollution. The degradation of monu The Action coordinates its scientific Ljubljana: Institut Josef Stefan ments and outdoor statues is well known, activities among the participating groups SPAIN but all artefacts, even those in exhibits or (see table) by organizing the exchange of Madrid, Universidad Autonoma storage rooms, are subject to degradation. samples and procedures. A second aspect Sevilla, Universidad UK The phenomena must be studied to under is to arrange for specialists to work Oxford: SPM, University of Oxford stand their cause and their kinetics, and to together for a short time, in a particular find out ways to slow them down or to pre laboratory, on artefacts of archeological vent them taking place. interest provided by the participating have been workshops and seminars in All these objectives are common to laboratories. Priority is given to the study Debrecen (on general aspects of using ion- the very large community of those who of artefacts proposed by archaeologists beam techniques to study archeological practice what is called today “archaeome and historians who define the archeologi artefacts), in Sevilla (with talks on ion- try” or more generally “application of sci cal pertinence of the analytical work. beam techniques for historians and ences to art”. Much of this work is based The Action also organizes workshops archaeologists), in Dresden (on the simu on elemental analysis, namely determin and experimental sessions on the con lation of the depth-profiling analysis of ing the concentration of elements present certed research at the rate of two meetings pigments), and in Paris (on problems of in an object. Until the 1960s, only chemical each year. Since the Action started there conservation in musea). The next work- techniques were available for analyzing composition. Since then, many others methods based on physical principles have been developed. They include microanaly sis using electron beam microscopes and microprobes and approaches based on various types of particle and photon spec trometers. This interest led to the con struction of major accelerator-based facil ities devoted to archaeometry such as the AGLAE accelerator at the Louvre (see pho tograph). The insert describes the princi ple accelerator-based techniques used for elemental analysis and their relative advantages. More recently, methods based on the The Accelerator Grand Louvre pour l'Analyse Elémentaire (AGLAE) at the Louvre Museum, Paris. The right-hand side use of accelerated ions - so-called ion- of the photograph shows the external beam assembly that allows the study of large artifacts under ambient beam analysis - have developed rapidly. conditions. The AGLAE laboratory was set up at the end of the 1980s mainly to provide within the museum itself To further exploit this approach it was powerful analytical tools for a large community of historians and archaeologists. COST G1 groups from Florence, decided in the early-1990s to launch a Namur, Orleans, and Oxford have collaborated with the laboratory for many years. 27 News 1996 Europhysics 230 PHYSICS AND SOCIETY Accelerator-based Elemental Analysis In comparison with methods involving electron-beam irradiation, the use of heavier particles allows measurements (see table) of the composition of objects under ambient conditions, a feature which is of great advantage in studying fragile materials (e.g., ancient manuscripts) and large items (e.g., statues, paintings) and for rapidly selecting regions to be analyzed (e.g., inclusions in potteries; solders on gold artefacts). The photograph on the left illustrates a typical experimental arrangement for analysis under ambient conditions employing a particle accelerator. A 0.7 mm in diameter proton beam is being used to analyze the various components (bulk wires, granulations, solders, etc.) on an anthropomorphic pendant made of tumbaga, an alloy with a low concentration of gold dating from the the pre-Columbian period. The Principle Accelerator-based Analysis Techniques A photograph of the experimental arrangement at Technique Incident energy Application LARN's ambient conditions PIXE facility in Namur, Surface techniques (1 -400 pm) Belgium, showing the relative positions of instruments. PIXE Particle-Induced X-ray Emission 0.5 to 7 MeV Elemental analysis of medium & heavy elements The X-ray detector for collecting signals from argon (in PIGE Particle-Induced Gamma-ray Emission 0.5 to 7 MeV Elemental analysis of light elements air) is seen in the upper part while the lower part shows PBS Rutherford Backscattering Spectrometry 0.5 to 7 MeV Depth profile analysis of medium & heavy elements in the main X-ray detector for identifying the elements light matrices present in the artefact under examination. The artefact NRA Nuclear Reaction Analysis 0.5 to 7 MeV Depth profile analyses of light elements (seen in the middle of the photograph) is an anthro CPM Charged Particle Activation Analysis 10 to 20 MeV Elemental analysis of 40 elements pomorphic pendant from the pre-Hispanic period Bulk analysis which is positioned for analysis at the exit window of FNAA Fast Neutron Activation Analysis 10 to 20 MeV Elemental analysis of 60 elements among medium & the evacuated accelerator beam pipe. heavy ones COST G1: Organization and Management shop, to be held in Namur in spring 1997, As archaeological items and works of art cover a very large variety of materials, six working groups have been organized, will focus on the damage that can arise in whose details are given below (together with a list of laboratories having expertise and publications in the various fields. fragile materials on exposure to ion-beam PAINT LAYERS SILICATE MATERIALS METALS irradiation. Coordinator: Ch. Neelmeijer, Dresden Coordinator: M. Schreiner, Vienna Coordinator: J.-N. Barrandon, Orléans Among the scientific collaborations Tel +49-351-591 32 54 Tel +43-158 81 62 61 Tel +33-2-3851 52 70 already established, one should include: Fax +49-351-591 32 85 Fax +43-158 81 61 37 Fax +33-2-38 51 76 88 • the depth-profile analysis of the layered Paintings: Dresden, Florence, Helsinki, Pottery: Antwerp, Athens, Debrecen, Iron: Helsinki Le Louvre (Paris) .Ljubljana, Namur, Helsinki, Madrid, Namur, Sevilla, Bronzes and brass: Antwerp,Budapest, structures of paintings (initiated by the Orléans, Oxford, Sevilla, Vienna Venice Ljubljana, Madrid, Namur, Orléans, Dresden group and involving a major col Manuscripts: Dresden, Florence, Le Glass: Bucharest, Debrecen, Le Louvre Sevilla laboration with the groups in Vienna, Louvre (Paris), Helsinki, Madrid, Orléans, (Paris), Namur, Orléans, Vienna Silver: Helsinki, Ljubljana, Madrid, Oxford Flints: Ljubljana, Le Loovre (Paris) Namur, Orléans, Oxford Paris, Namur, Liege, Sevilla, and Florence); Stones: Antwerp, Le Louvre (Paris) Gold: Le Louvre (Paris), Madrid, Namur, • the study of the technology of ancient ORGANIC MATERIALS Orléans, Oxford, Sevilla glasses (proposed by the Debrecen and Coordinator:

Load more