• M. Tzoufras, S. Fonseca, W. Lu, W.B. Mori, L.O. Silva, F.S. Tsung
  UCLA, Los Angeles, California

Recently, several groups around the world observed mono-energetic beams between 80 MeV and 170 MeV using ~15 TW lasers. We have begun a comprehensive study of the acceleration of electrons by the interaction of ultra-intense short and ultra-short laser pulses with underdense plasma. We concentrate our parameter space to existing and near term laser parameters, i.e., laser parameters between 30 and 100 TW. We use 3D particle in cell simulations using the code OSIRIS. The goal is to show that the generation of mono-energetic beams with energy beyond 1GeV with current and near future laser systems is possible without the need for any external injection. In this ultra-relativistic regime the laser blows out all the electrons forming an almost spherical cavity. Some electrons are self-injected in the blowout region and accelerated by the laser wakefield to ultrahigh energy. In order to maximize the energy gain, the beam charge and quality, we need an improved understanding of the wakefield generation as well as of processes such as self-injection and beam loading. We will provide theoretical estimates and verify their validity with 3D simulations. We will address possible limitations of particle acceleration in this regime.

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