Development of a Nuclear-Activation Based Diagnostic for Measurement of Laser-Driven Ion Sources in Ion Fast Ignition Experiments

Laser-driven ion acceleration via the widely studied mechanism of target normal sheath acceleration (TNSA) remains a subject of significant interest for a range of applications in high energy density science, including certain inertial fusion energy schemes. [1] In TNSA, ultrashort, high-intensity lasers are used to generate energetic ion beams. While proton acceleration has been widely studied, the spatial distribution of heavier laser-accelerated ions has not yet been directly measured and is crucial for understanding mass-dependent acceleration dynamics. Previous work has used auto-radiography of proton-activated copper and silver samples to measure the spatial profile of laser-driven protons with high spatial resolution. [2] We extend this work through both simulation study and experiment to deuterons, a heavier ion species. Using G4Beamlines, a Monte-Carlo based particle-tracking software, this work modeled deuteron activation of several candidate materials. The prototype of this diagnostic was then fielded at Orion Laser Facility with our choice candidate activation material. Results of this synthetic diagnostic study, along with preliminary diagnostic results obtained in experiment, demonstrate promising outcomes for measuring the spatial profile of laser-driven deuterons through nuclear activation. Current and future developments involve optimizing this diagnostic, calibration efforts, and its utilization in an IFI experiment at the Omega Laser Facility in Summer 2026.