Shedding Light on Art – A Particle Accelerator in Paris

A digitally zoomed picture of an antique Byzantine ceramic bowl under archaeological forensic scrutiny by AGLAE, the particle accelerator at the Louvre Museum in Paris, France. Artwork: NaturPhilosophieArt in a New Light

The World’s only particle accelerator dedicated to analysing artworks is back online at the Louvre Museum in Paris. 

The particle accelerator was rebuilt to allow it to investigate paintings without risk of damaging the artworks.

The unique machine is 37 metre (88 ft) long.

The upgrade cost of €2.1m (£1.8m, $2.5m) was paid for by the Centre de Recherche and Restauration des Musées de France (C2RMF), which is independent of the Louvre Museum.

AGLAE (Grand Louvre Elementary Analysis Accelerator) implements ion beam-derived methods of analysis, which are now widely used in materials science:

  • charged particle-induced X emission (PIXE)
  • Rutherford back-scattering spectrometry (RBS)
  • nuclear reaction analysis (NRA), a variant of which is called PIGE (charged particle-induced gamma emission)
  • elastic recoil detection analysis (ERDA)

Recently, a spectrometer for recording ionoluminescence (IBIL) was installed on the extracted beamline.

These methods have very good analytical performances.

But above all, they are especially non-destructive, which is crucial, given the precious and often unique nature of the artworks.

 

Infographic about the Louvre's very own Particle Accelerator. The only particle accelerator in the World to be uniquely dedicated to art. The particle accelerator at the Louvre authenticates and analyses ancient objects without damaging them. 1) Particles (such as protons, alpha particles and helium ions) are speeded up to 20,000 - 30,000 km per second. 2) Beam of high-energy particles bombards the artefact. 3) Artefact emits x-rays and gamma rays. 4) Detectors identify chemical elements present in the outer layers of the object to show where, when and how it was made. 2017 upgrade: New AGLAE (French acronym for Grand Louvre Elementary Analysis Accelerator) is automated, more sensitive and less likely to damage artefacts than its 30-year-old predecessor. Examples of applications: Analyses glass, ceramics and metals to determine where the minerals were mined. Has confirmed a quartz crystal skull, thought to be Maya or Aztec, dated in reality from the 18th-19th century. Detects chemical traces of paint to reveal an item's original colours. Source: CNRSFinding the Fake

The ancient artworks were bombarded with helium and hydrogen atoms, travelling at the speed of light, up to 30,000 km/h (18,600 mph).  The radiation emitted was analysed to determine the chemical make-up.

The first objects to be tested by the newly configured accelerator, known as Aglae, included votive statues of the Lares – Roman household gods.

Analyses are carried out by non-destructive ion beam analyses, by PIXE (Particle Induced X-Ray Emission) and PIGE (Particle Induced Gamma-Ray Emission), at the Accélérateur Grand Louvre d’Analyses Elémentaires (AGLAE)), in order to obtain the elemental compositions of the different materials composing ceramics (body, slip, glaze).

Prior to the upgrade, paintings were rarely analysed with the accelerator for fear the particle beam might alter the colours.

 

PIXE and PIGE analyses

Back in 2014, Yona Waksman and Jacques Burlot went to the Centre de Recherche et de Restauration des Musées de France (C2RMF) in Paris, in order to analyse Byzantine and Early Turkish ceramics coming from archaeological sites  at Ephesos, Pergamon, Sardis and Iznik.

They also examined items from museum collections (Cité de la Céramique, Sèvres).  The study was carried out with the collaboration of Anne Bouquillon (C2RMF) and of Laurence Tilliard (Cité de la Céramique, Sèvres). It proposed to investigate provenance and technologies of different ceramic types such as Aegean ware and Miletus ware.

Those analyses are designed to investigate the origin of museum examples, and the introduction of new technological features in pottery production during the transition between the Byzantine and early Turkish periods in Western Turkey.