Photodisintegration studies of actinides with laser-driven x-rays*

We present results on x-ray photo-activation and disintegration of actinides. Two x-ray sources are compared: bremsstrahlung and Thomson driven by laser-wakefield accelerated (100-400 MeV) electron beams. Bremsstrahlung is generated from high-Z converter and narrow band x-rays (\textless 50{\%} energy spread) are generated by Thomson scattering an intense laser pulse off the electron beam, resulting in high-flux (10$^{8}$ photons s$^{-1})$, polarized light, that is tunable [1]. We present data on delayed gamma rays and neutrons, and the production of fission fragments with half-lives from minutes to hours from photofission of $^{238}$U. We discuss possible selective activation and identification of specific materials and compare experimental results with simulations. \\[4pt] [1] S. Chen et al., Phys. Rev. Lett. 110, 155003 (2013).