Numerical Studies of Phase Diversity Sampled Relativistic Electron Bunches

The measurement and recording of terahertz (THz) electric fields is of special interest to beam physics, as the electric fields of temporally short relativistic electron bunches have frequency components that extend into the THz range. These frequency components are challenging to measure using conventional methods, as this range of frequencies are too high for electronic systems, and are too low for (most) optical systems. Various pump-probe methods have been developed to record such fields, from the scanning electro-optic sampling technique to the spectral encoding/decoding technique in the field of terahertz time domain spectroscopy. In this paper, we present our progress on numerical simulations of the phase diversity electro-optic sampling (DEOS) technique originally proposed in [1]. EOS consist of encoding the THz-pulse electric field on the spectrum of an optical laser pulse using the Pockel's effect induced by the THz passing through the crystal. The optical pulse to recover the information encoded on the spectrum ultimately providing the THz-pulse distribution. We present a numerical model of the technique and its application to recover the temporal shape of electron bunches produced at the Argonne Wakefield Accelerator (AWA).