Production of carbon-11 for PET preclinical imaging using a high-repetition rate laser-driven proton source.

Most advanced medical imaging techniques, such as positron-emission tomography (PET), require tracers that are produced in conventional particle accelerators. This paper focuses on the evaluation of a potential alternative technology based on laser-driven ion acceleration for the production of radioisotopes for PET imaging. We report for the first time the use of a high-repetition rate, ultra-intense laser system for the production of carbon-11 in multi-shot operation. Proton bunches with energies up to 10-14 MeV were systematically accelerated in long series at pulse rates between 0.1 and 1 Hz using a PW-class laser. These protons were used to activate a boron target via the 11 B(p,n) 11 C nuclear reaction. A peak activity of 234 kBq was obtained in multi-shot operation with laser pulses with an energy of 25 J. Significant carbon-11 production was also achieved for lower pulse energies. The experimental carbon-11 activities measured in this work are comparable to the levels required for preclinical PET, which would be feasible by operating at the repetition rate of current state-of-the-art technology (10 Hz). The scalability of next-generation laser-driven accelerators in terms of this parameter for sustained operation over time could increase these overall levels into the clinical PET range.

Combined laser-based X-ray fluorescence and particle-induced X-ray emission for versatile multi-element analysis.

Particle and radiation sources are widely employed in manifold applications. In the last decades, the upcoming of versatile, energetic, high-brilliance laser-based sources, as produced by intense laser-matter interactions, has introduced utilization of these sources in diverse areas, given their potential to complement or even outperform existing techniques. In this paper, we show that the interaction of an intense laser with a solid target produces a versatile, non-destructive, fast analysis technique that allows to switch from laser-driven PIXE (Particle-Induced X-ray Emission) to laser-driven XRF (X-ray Fluorescence) within single laser shots, by simply changing the atomic number of the interaction target. The combination of both processes improves the retrieval of constituents in materials and allows for volumetric analysis up to tens of microns and on cm2 large areas up to a detection threshold of ppms. This opens the route for a versatile, non-destructive, and fast combined analysis technique.