A spectroscopic study of ancient Roman a fresco fragments from the archaeological site Casa di Augusto at Palatino: towards an on-site multidisciplinary project

In this paper we present the first stage of a joint Italian-Swedish project which focuses on the assessment of the conservation status of the house of Augustus, which was the private residence of the Emperor Augusto and is located in the south-west area of the Palatino hill in Rome, Italy. The main objective of the project is to document and record the status of some sections of the site by using different non-invasive imaging techniques, from high-precision colour 3D Laser Scanner to fluorescence hyperspectral lidar imaging. The studies include the characterisation of historic materials, but also the detection and characterisation of biodeterioration processes on the walls for environmental risk assessment. The first stage of the project focussed on a spectroscopic study of several fragments coming from the archaeological site of House of Augustus. Fluorescence lidar hyperspectral data were first acquired on the sample to investigate the potential for their characterisation on the basis of their fluorescence properties with a remote sensing technique. The samples were also characterised using Attenuated Transmission Reflectance (ATR) Fourier Transform InfraRed (FT-IR) and Raman spectroscopy for the identification of the pigments in the frescos. Results also demonstrated the potential of lidar hyperspectral imaging on frescoes, through the characterization of several pigments on the basis of their fluorescence spectral signatures.