High-sensitivity optical tomography of gas jets for laser-plasma accelerator

We present a four-pass interferometry setup for analyzing gas target density profile. Analyzing these profiles is crucial for applications such as Laser Wakefield acceleration (LWFA) and X-rays generation from laser-plasma interaction. We introduce an experimental setup allowing precise measurement of the phase shift caused by propagation of laser through gas medium. Reconstruction of 3D density profiles of gas targets is obtained using standard tomography methods, like Filtered Back Projection (FBP). Due to precise measurement by the four-pass interferometry setup various details such as shock in the density distribution can be observed.