English: A 3D OSIRIS PIC simulation of LWFA in the blowout regime, rendered in parallel using Rayven. Plasma electron density is shown from low:blue to high:red, while black represents density below the background. The laser pulse (not shown) is moving to the right and is so intense that it expels all the plasma electrons from its path and creates a bubble-like feature in the plasma. This bubble fea- ture still contains positively charged ions due to their large mass and hence has strong electric fields that pull electrons into the bubble and accelerate them as they ride along with the laser pulse.