Shielding assessment for the ELI high intensity laser beamline facility in Czech Republic

The production of laser-accelerated, high energy and high current particle beams requires a proper shielding assessment, especially when high intensity laser systems operate in repetition rate. The ELI (Extreme Light Infrastructure) future european facility in Czech Republic, where different optional laser beamlines are foreseen, will offer versatile electron and proton/ion sources, emitting in an unprecedented energy range (up to about 40 GeV for the electron case). For this facility a first extensive study that includes shielding and activation calculations for the 300 J laser beamline, which is the most critical for electron acceleration experiments, has been performed. Starting from analytical calculations, as well as from dedicated simulations, the main radiation fields produced in the laser-matter interaction have been defined. These fields have been then characterized as "source terms" in a full simulation with the Monte Carlo code FLUKA, where the produced secondary radiation has been studied to assess a proper shielding. The first results for the ELI shielding for the electron case, together with the activation calculations that drove several material solutions, are here presented and discussed.