Self and Ionization-injection in Lfwa for Near-term Lasers∗

In plasma based acceleration (PBA), the methods of injecting high quality electron bunches into the accelerating wakefield is of utmost importance for various applications, including next generation light sources and high energy colliders. Numerous simulations are being conducted in order to study various methods of injection and to optimize the beam parameters. Particle-In-Cell simulations using codes such as OSIRIS are used to model PBA. 3D simulations are possible in some cases but are computationally expensive. 2D simulations are computationally less expensive, but 2D simulations in cartesian coordinates only provide qualitative agreement and 2D simulations in cylindrical coordinates cannot model laser wakefield acceleration (LWFA) at all and cannot include important physics such as hosing and low mode azimuthal mode asymmetries for particle beam drivers (PWFA). Here we discuss one method for reducing the computational load of a 3D simulation into those comparable to a 2D simulation that can model LWFA and include hosing. It utilizes a truncated azimuthal mode expansion. We describe how this expansion has been included into the OSIRIS simulation framework and show preliminary results.