Description
Laser-plasma particle acceleration based on solid targets [1] is promising for many applications, from nuclear medicine to materials characterization. Laser-plasma sources can generate different radiations (e.g., ions and photons), allow for energy tuning, and can operate within potentially compact setups. Control over the laser (e.g., intensity) and target parameters (e.g., thickness) enables one to tune the maximum energy of accelerated ions. Therefore, laser-plasma sources represent promising alternatives to conventional accelerators which, although based on mature technologies, remain limited in terms of flexibility and compactness.
Particle Induced X-Ray Emission (PIXE) and X-Ray Fluorescence Spectroscopy (XRF) are complementary materials characterization techniques used in several fields including artworks analysis [3]. They rely on the irradiation of samples with protons and photons to induce characteristic X-ray emission. PIXE and XRF could benefit from the use of laser-plasma sources [4]. Indeed, the energies of the laser-driven protons and photons are suitable for the characterization of cultural heritage materials.
Here, we present artworks characterization with laser-plasma sources via laser-driven PIXE and XRF. We performed a campaign at the ELIMAIA beamline [5] (ELI Beamlines) driven by the HAPLS laser. Using a proof-of-principle setup [2], laser-driven protons and photons were transported in air to irradiate certified materials, medieval bronzes, and Iron Age ceramics. We measured the characteristic X-rays emitted by the sample, and the spectra were analysed with a numerical tool that integrates the theoretical description of PIXE in the PyMCA code [6] for XRF analysis. In this way, it is possible to determine the elements present in the samples and their concentrations. This study lays the foundation for the development of laser-plasma accelerators tailored to the characterization of cultural heritage materials, suggesting that this suorces could achieve results comparable to conventional accelerators while maintaining their inherent versatility.
[1] A. Macchi et al., Rev. Mod. Phys (2013) 85-2
[2] F. Mirani, et al., Phys. Rev. Appl 24.1 (2025):014017
[3] L. Sottili, et al. Appl. Sci 12.13 (2022):6585
[4] F. Mirani et al., Sci. Adv (2021) 7-3
[5] D. Margarone, et al. Quantum Beam Sci 2.2 (2018):8
[6] V. A. Solé, et al. Spectrochim. Acta B 62.1 (2007):63-68.