High-energy electron radiography system with low chromatic aberrations based on active plasma lenses

A novel high-energy electron radiography system combined with an active plasma lens (APL) has been designed for the first time and validated by simulation studies. The system consists of a 50-MeV electron linear accelerator followed by a 3-cm-long capillary with a discharge current up to hundreds of amperes. With the APL, the distance from the object plane to the imaging plane can be reduced from 5 m to 45 cm with a magnification factor (MF) of 20, and pictures with 1.1-$\text{μ}\mathrm{m}$ spatial resolution can be obtained. The effects of lens chromatic aberrations, imaging blurring, and the uniformity of the plasma discharge current are shown to be significant in obtaining a high-spatial-resolution radiograph, which have been discussed in this work. Such a plasma-based imaging lens has a high tolerance for chromatic aberrations, is suitable for imaging thick target materials, and has radial symmetric focusing and adjustable focusing gradients. Furthermore, a cascaded high-MF radiography system based on APLs has been proposed to improve spatial resolution.