Thomson Scattering Imaging From Ultrashort Ultraintense Laser Interaction With Gas

Laser-plasma acceleration can provide acceleration gradients which are thousands of times stronger than conventional electron accelerators. The laser propagation length is a crucial parameter that must be extended to achieve high-energy electrons. Here, we show that color images of the laser-plasma interaction region taken from the direction perpendicular to the polarization plane are a powerful tool to discriminate between Thomson scattering and plasma self-emission, leading to a precise measurement of the propagation length.