Proposed Method for High-speed Plasma Density Measurement in Proton-driven Plasma Wakefield Acceleration

摘要

Recently a proton-bunch-driven plasma wakefield acceleration experiment using the CERN-SPS beam was proposed. Different types of plasma cells are under study, especially laser ionization, plasma discharge, and helicon sources. One of the key parameters is the spatial uniformity of the plasma density profile along the cell that has to be within < 1% of the nominal density (6 × 10~(14) cm~(-3)). Here a setup based on a photomixing concept is proposed to measure the plasma cut-off frequency and determine the plasma density.