Electron Dynamics in a Relativistic Central Field Approach Associated with Laser Acceleration of Electrons

We perform 2D PIC simulations and observe different scenarios of electron trajectories trapped inside the bubble formed during the laser wakefield acceleration process (LWFA). The trajectories can close on the inside or on the outside of the bubble. The evolution of maximum energy of the injected electrons in both cases is evaluated. We propose an analytic approach based on a relativistic central field model for describing the attraction of electrons near the bubble edge and compare it with the simulations.