Exploring the Self-modulated Regime of Laser Wakefield Acceleration on the Titan Laser

Laser wakefield acceleration (LWFA) describes the process in which an intense laser pulse interacts with a gas, creating a plasma and accelerating electrons that travel in the wake of the pulse. These electrons also can wiggle during the process, producing betatron X-rays. Most experimental LWFA investigations are performed with ultrashort laser pulses (less than 100 fs), but the self-modulated regime (about 1 ps) remains relatively unexplored. An experiment on the Titan laser was performed to characterize the self-modulated regime using interferometry and electron, X-ray and Raman spectroscopies. Observed electrons had significant angular deflections and energies up to 170 MeV.