High-resolution spectroscopic X-ray diagnostics for studying the ion kinetic energy and plasma properties in a Z-pinch at stagnation

Doubly-curved-crystal spectroscopic systems are used to obtain time-resolved measurements of Ne K emission from the stagnating plasma in a Ne-puff Z-pinch experiment. These systems, with a spectral resolving power of /spl cong/ 6700 (only limited by the crystal rocking curve) and simultaneous z-imaging with a resolution /spl cong/ 0.1 mm, are used to obtain the time history of the ion kinetic energy at stagnation from the line profiles of Ly/spl alpha/ satellites, which were verified to be optically thin. The measurements allowed for tracking the ion energy throughout the entire K-emission period. It was found that the ions lose most of their kinetic energy during the K-emission period, i.e. before the electrons cool down enough to terminate the K-emission, and before the ions recombine to Li-like charge state. Also in this study, the profile of the optically thin intercombination line was used to investigate the velocities of the He-like ions. Together with the determination of the electron density from satellite ratios, absolute line and continuum intensities, time resolved observation of the plasma size, and collisional-radiative and radiation-transport calculations, these data are used to study the various contributions to the energy deposition and energy losses of the plasma at stagnation.