Thin-sections of painting fragments: opportunities for combined synchrotron-based micro-spectroscopic techniques

Synchrotron Radiation (SR) - based techniques such as SR-μ Fourier Transform InfraRed (FTIR) spectroscopy, SR-μ X-Ray Fluorescence (XRF), SR-μ X-Ray Absorption Near Edge Spectroscopy (XANES) and SR-μ X-Ray Diffraction (XRD) are increasingly used for the study of cultural heritage materials, as they offer enhanced spatial resolution and chemical sensitivity. For such analyses, painting fragments are usually prepared as thick (typically several hundreds of micrometers) polished cross-sections. The capabilities of these SR techniques can be significantly improved (enhanced data quality, reduced acquisition time, new imaging capabilities, improved lateral and in-depth resolution, reduced dose, etc.) if carried out on thin-sections, i.e. less than ~30 μm in thickness. This paper discusses and illustrates the different motivations in terms of related increased analytical capabilities for SR-μFTIR, SR-μXRF, SR-μXANES and SR-μXRD. Corollary to the optimization of the procedures for single SR micro-analytical technique, a specific discussion is focused on the challenges of their combination.