High resolution radiography with Self-Modulated laser wakefield accelerator driven X-rays

We are developing broadband X-ray sources with high spatio-temporal resolution to better image High Energy Density Science (HEDS) phenomena. A broadband X-ray source driven by Self-Modulated laser wakefield acceleration (SM-LWFA) was generated at the Jupiter Laser Facility, with photon energies from 10 KeV to > 1 MeV, and used to image an inertial confinement fusion hohlraum target with tungsten sphere positioned at the center, as well as a modified air force resolution target. These X-ray radiographs enabled us to determine the source size of the X-rays, in addition to the spectra (measured separately), using either the diffraction pattern cast by the edge of the resolution target, or by comparing the radiograph with a simulated image created by a modified X-ray ray-tracing model. We compare several different methods using SM-LWFA accelerated electrons to generate X-rays, including Betatron, Inverse Compton Scattering, and Bremsstrahlung. Due to the different spectral and resolution characteristics of these processes, they offer different performances for use in radiography in HEDS experiments. We also compare these radiographs with images taken at the Texas Petawatt Laser, where the sources are driven by blowout LWFA. This work will help us understand the variation of X-ray source characteristics with different laser-plasma parameters, and its impact on HEDS application experiments.