TITLE:
Influence of a Static Magnetic Field on Beam Emittance in Laser Wakefield Acceleration
AUTHORS:
Mathieu Drouin, Alain Bourdier, Quentin Harry, Sébastien Rassou
KEYWORDS:
Laser Wakefield Acceleration; Magnetic Field; Beam Emittance; Beam Loading
JOURNAL NAME:
Journal of Modern Physics,
Vol.3 No.12,
December
31,
2012
ABSTRACT:
The enhancement of trapping and the optimization of beam quality are two key issues of Laser Wakefield Acceleration (LWFA). The effect of a homogenous constant magnetic field B0, parallel to the direction of propagation of the pump pulse, is studied in the blowout regime via 2Dx3Dv Particle-In-Cell simulations. Electrons are injected into the wake using a counter-propagating low amplitude laser. Transverse currents are generated at the rim of the bubble, which results in the amplification of the B0 field at the rear of the bubble. Therefore the dynamics of the beam is modified, the main effect is the reduction of the transverse emittance when B0 is raised. Depending on beam loading effects the low energy tail, observed in the non-magnetized case, can be suppressed when B0 is applied, which provides a mono-energetic beam.