|Art and Arqueometry|
The cultural heritage has been one of the aggregating factors of community life and is today a major economic resource. Archeometric applications of ion beams are, since its ionception in 2002, one of the traditional research topics of the CMAM and will continue to be in the cming years. This activity has seen the CMAM researchers collaborating with some of the major museums in the world, as well as with academics, curators and restorers of Spain.
CMAM has been an important performer in the development that ion beam techniques have seen in the last decade, being involved, as promoter, in the COST European Cooperation actions, COST G1 and G8, focused on the application of non destructive analytical techniques to Heritage and Conservation Science. CMAM continues to be a promoter of archeometric research: two of its researchers are included in the National Network of Heritage experts recently created by the University of Jaen as a result of a project funded by the Ministry of Science and Innovation in the framework programme “International Campus of Excellence” and the laboratory is included in the network of services available to members of Net Heritage, the European network for research on tangible heritage. The studies performed with Ion Beam Analysis techniques have allowed, in general, to add value to our cultural heritage, through the attribution of works, provenance studies, and the understanding of manufacturing techniques. They have also allowed, through the extended characterization of the conservation state of materials, the planning of the most efficient restoration and/or maintenance of artistic objects. Being most of the heritage public, the benefits that these activities bring to our society are obvious, and in particular those CMAM have contributed and will contribute to in Spain.
CMAM counts on, for the study of cultural heritage, a broad range of tools and a measuring station that allows for flexible planning of the analyzes. The station is based on a focused microbeam produced by a quadrupole doublet with high demagnificacion and extracted in air through a ultrafine Si3N4 (silicon nitride) window, 200 nanometers thick. In such a way, three millimeters away from Si3N4 window, even when diffused in air, the ion beam has a nearly Gaussian spatial distribution with a FWHM of 40 micrometers. Associated to this micro-beam, there is a table provided with XYZ movements controlled by computer, which has a real positioning precision (including vibration and stepping motors starts) of some tens of microns. The table has a maximum load of 30 kg so it can accommodate both small samples like fragments and resin embedded sections, and whole objects of medium-large size. It is, therefore, possible to irradiate micrometer-sized structures of a sample or, if needed, to make scans over a whole object. The analytical part includes three complementary techniques usable in parallel: PIXE, PIGE and RBS. Their application results in a wide possibility of compositional and structural characterization of complex objects, with layered structure and formed by both light and heavy chemical elements. After years of intensive use, the external microbeam line still demands nearly 20% of beamtime use at CMAM, and is subject to constant improvement. For the near future, a further more compact and integrated drawing of the microbeam end of the line is foreseen, aiming the goals of improving the reproducibility charge measurements, simplifying the beam size measurements, and freeing space to accommodate an in-vacuum RBS system, an integrated system for iono-luminescence, and a new gamma detector, LaBr3 type, for high efficiency and high resolution PIGE. So revised, the system will allow to perform routinely measurements that have demonstrated in recent studies, promising perspectives, like the combination of PIXE and RBS in the study of metals and PIGE for the detection of light elements in artificially altered gemstones.