Ultra-Bright Foam-based Particle and Radiation Sources: From PHELIX to ARC at NIF

Over past years, collaboration between the plasma physics groups at the Frankfurt University, GSI Darmstadt, and FSU Jena, alongside colleagues from ENEA Frascati, LPI and JIHT in Moscow, has pioneered a novel approach to generating ultra-intense laser-driven secondary sources of particles and radiation using low-density foams.

This methodology, successfully demonstrated at the PHELIX laser at GSI has enabled a wide range of multidisciplinary applications. Key achievements include advancements in laser-driven particle acceleration, the efficient production of isotopes and neutrons, and the observation of the ultra-high dose FLASH effect using high-charge, laser-accelerated electrons, documented in high-impact journals including Nature Communications and Scientific Reports.

Leveraging the expertise in foam-target interactions developed at PHELIX, we proposed the NIF Discovery Science project titled 'Ultra-bright MeV photon sources driven by direct laser accelerated (DLA) electrons on ARC'. ARC—the Advanced Radiographic Capability short-pulse laser facility—was originally built to produce high-energy MeV photon sources for radiographing the D-T capsule at the moment of implosion.

The campaign was executed in February 2026, supported by a dedicated team of NIF scientists, including Hui Chen, Shaun Kerr, and Dean Rusby. Preliminary analysis of the experimental data confirms the campaign's success, demonstrating an up to 10-fold increase in the fluence of MeV Bremsstrahlung in the region of giant dipole resonance per Joule laser energy than previously reported at ARC. This achievement represents a significant milestone in the development of laser-driven particle and radiation sources, with profound implications for inertial confinement fusion (ICF) diagnostics at the NIF and high-energy-density physics facilities worldwide.