Integrated quantitative PIXE analysis and EDX spectroscopy using a laser-driven particle source

Among the existing elemental characterization techniques, Particle Induced X-ray Emission (PIXE) and Energy Dispersive X-ray (EDX) spectroscopy are two of the most widely used in different scientific and technological fields. Here we present the first quantitative laser-driven PIXE and laser-driven EDX experimental investigation performed at the Centro de L\'aseres Pulsados in Salamanca. Thanks to their potential for compactness and portability, laser-driven particle sources are very appealing for materials science applications, especially for materials analysis techniques. We demonstrate the possibility to exploit the X-ray signal produced by the co-irradiation with both electrons and protons to identify the elements in the sample. We show that, using the proton beam only, we can successfully obtain quantitative information about the sample structure through laser-driven PIXE analysis. These results pave the way towards the development of a compact and multi-functional apparatus for the elemental analysis of materials based on a laser-driven particle source.Comment: This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (ENSURE grant agreement No. 647554). Submitted to Science Advances on 20th May 2

Prompt Gamma Imaging for Dose Monitoring in Carbon Ion Radiation Therapy: A Simulation Study

In-vivo range verification has been a hot topic in particle therapy since two decades. Many efforts have been focused on proton therapy, while fewer studies were conducted considering a beam of carbon ions. In this work we show, through a simulation study, that it is possible to recognize in a pixelated detector a Prompt Gamma profile generated by the interaction of ions with matter (which is correlated to the Bragg curve) despite a very large neutron background typical of carbon-ion irradiation. In addition, we estimate of the theoretical uncertainty on the particle range determination, considering a Carbon pencil beam with different numbers of ions. For this purpose, we performed Monte Carlo simulations with the software FLUKA and, for data analysis, we implemented three different analytical methods to estimate the theoretical accuracy in the range retrieval for the simulated set-up. Results positively confirmed the correlation between the Bragg peak and the detection profiles. The analysis of the simulation data brought to a precision of few millimeters with a realistic spill intensity, with the three cited methods coherent between them in their predictions. Finally, due to the positive indications of our study, we planned an experimental campaign to verify our simulated results and further investigate if the Prompt Gamma Imaging technique can be applied to carbion ion treatments

Experimental Verification of Prompt Gamma Imaging Technique during Carbon Ion Radiation Therapy

Prompt Gamma Imaging (PGI) is a technique here considered to verify the range of the particle beams in real-time during Carbon Ion Radiation Therapy (CIRT). In this framework, PGI measurements are strongly affected by the limited number of emitted prompt gammas (PGs) and by the presence of a neutron background. A recent study performed using Monte Carlo simulations demonstrated that, despite these limitations, a prompt-gamma camera based on a knife-edge collimator and a pixelated detector could achieve the required sensitivity to measure a shift of the C-ions range of an energy layer during a clinical treatment. Therefore, a prompt-gamma camera based on this concept was developed in order to experimentally validate the simulation results. The camera is based on a compact scintillation detector composed by a 2"x2" pixelated LYSO crystal (6 mm crystal pitch) coupled 1:1 with an array of SiPMs and by its complete readout electronics, which uses a custom-developed readout ASIC and an FPGA-based DAQ. The spectroscopic and positioning performance of the detector have been characterized, achieving the performance required by the application. An experimental campaign will be carried out in May 2023 at CNAO to demonstrate the system capability to verify the beam range during C-ion treatments. The results of this experimental measurements will be presented at the conference