Five-channel K-shell line emission imaging of Z-pinch plasmas

A five-channel, in-chamber, X-ray imager employing five pinholes and five logarithmic spiral crystals is developed to obtain five monochromatic K-shell line images of the Al wire array Z-pinch plasmas on the Yang accelerator in one shot. This imager is compact, and easy to install and align. It has high energy resolution (less than 1.3 eV), and thus can easily distinguish the images of the He-like resonance line (1 598.4 eV) and its inter-combination line (1 588.3 eV), and the H-like resonance line (1 727.7 eV) and its inter-combination line (1729 eV) of Al from each other. Limited by the drive capability of the Yang accelerator, these images are constructed by several discrete hot-spots distributed around the axial line of the plasmas with cylindrical shape, where the temperature and density of electrons are higher than other regions. In addition, the intensity is higher and the area of hot-spots is wider for the He-like line images than for the H-like line images, which indicates that the electron temperature is not high enough so that the number of H-like ions is far less than that of He-like ions.