Isabella Pagano Thesis Defense

Abstract: Self-modulated (SM) and blowout regime laser wakefield acceleration (LWFA) of electrons, can also produce novel flexible and tunable X-ray sources of interest for High Energy Density Science (HEDS) applications. The source size characterization of SM-LWFA based X-ray sources at Titan in the Jupiter Laser Facility at Lawrence Livermore National Laboratory (120 J, .7 ps) was performed. At Titan, electron beams can be accelerated up to ~150 MeV, with broadband electron and X-ray spectra, and high flux (> 10^10 photons/keV/sr) and charge (nC). These electron beams were used to produce X-ray sources from Betatron, inverse Compton scattering, and bremsstrahlung processes. The goal was to understand which source characteristics (spectral, spatial resolution) made them suitable as an X-ray backlighter for experiments with specific source requirements. A high spatial (< 10 micron), low energy (<30 keV), X-ray source was needed for a separate applications experiment, inertial confinement fusion fuel capsule metrology with a blowout LWFA Betatron X-ray source at the Advanced Laser Light Source (2.5 Hz, 22fs, 3.2 J). Laser-plasma driven sources are flexible, tunable, and being plasma-driven, are ideal for scenarios such as a future inertial fusion energy plant. A full tomographic reconstruction is performed, and X-ray phase contrast radiographs benchmark a LWFA driven source for the application of ICF fuel capsule metrology. The overarching goal connecting these projects, is to bridge the gap between current LWFA based X-ray sources and the required parameters for applications.