Radiographic results from the NTLX series of hydrodynamic experiments

Summary form only given, as follows. The NTLX series of experiments are focused on measuring the shock induced hydrodynamic flow of a Sn-PMMA target. Of particular interest are the trajectories and velocities of the shock and the material interfaces in the target. These data provide an important benchmark for various hydrodynamic codes currently used to predict the behavior of shocked materials. For these experiments multi-frame flash X-ray radiography is used to image the position of the Sn-PMMA target interface and the location of the shock in the PMMA at specific times. During the experiment four radiographs are taken having a line-of-sight coincident with the target's axis of symmetry. Four Los Alamos designed Marx driven X-ray diode sources are used, each one having a duration of 25 ns FWHM thereby freezing the motion of the target. The X-ray spectrum from the sources has an end-point energy of /spl sim/300 keV, with a strong component of tungsten K-line radiation (/spl sim/60 keV), and, as such, we do not record transmission of X-rays through the Sri part of the target. However, X-rays from the source are transmitted through the PMMA part of the target allowing determination of the location of the Sn-PMMA interface as a function of time. Also, given the density increase in the PMMA when shocked the location of the shock in the PMMA can also be tracked as a function of time. The resulting radiographs are analyzed to determine the time the shock enters the PMMA, the trajectory, velocity and shape of the shock in the PMMA and of the Sn-PMMA interface. In this talk we will discuss the x-ray diagnostic, the analysis of the data, and compare the results to the theoretical predictions.