Femtosecond hard-x-rays via Thomson-scattering on electrons produced by ultra-intense laser wake field acceleration

Summary form only given, as follows. In the present work, we study experimentally with 12 TW, 50 fs Ti-sapphire laser set-up and numerically through a multidimensional particle-in-cell simulation two mechanisms of generation of femtosecond electron bunches in gas jet suitable for efficient Thomson scattering. The first is the LWFA of electrons injected due to wave-breaking on a shock-wave produced by a laser prepulse in a He gas-jet. This mechanism allows us to produce a narrow-coned electron bunch with duration around 30 fs. Results of measurements agree well with two-dimensional hydrodynamics and particle-in-cell simulations.