Simulation of self-modulated laser wakefield acceleration using few TW in downramp injection and ionization injection regimes

Simulations of transitional self-modulated laser wakefield acceleration driven by laser pulses of a few terawatts are discussed, comparing a downramp-based injection regime with an ionization injection regime. We demonstrate that a configuration using an N ₂ gas target and a laser pulse of ∼75m J with ∼2T W peak power is a good alternative as a high repetition rate system that produces electrons of many tens of MeV, pC charge, and emittance of the order of 1 mm mrad.