Consequences of laser transverse imperfections on laser wakefield acceleration at the Apollon facility

Abstract

With the currently available laser powers, it is possible to reach the blowout regime in the Laser WakeField Acceleration (LWFA) where the electrons are completely expelled off-axis behind the laser pulse. This regime is particularly interesting thanks to its linear focusing forces and to its accelerating forces that are independent of the transverse coordinates. In fact, these features ensure a quite stable propagation of electron bunches with low phase-space volume. In this context, the Apollon laser is designed to reach an exceptional multi-petawatt laser peak power, thus aiming at achieving unprecedented accelerating gradients and bringing a scientific breakthrough in the field of LWFA. Since the quality of the self-injected electron bunches is very sensitive to the condition of the laser, it is very important to take into account realistic laser features when performing LWFA simulations. In this paper, we aim at understanding the implications of laser imperfections on the electrons produced with the self-injection scheme in the bubble regime. For this purpose, we carry on a numerical study of LWFA where we include experimentally measured laser profiles from the Apollon facility in full three dimensional Particle-In-Cell simulations