Investigating the Formation of X-Pinches Using L-Shell Time Resolved Spectroscopy

The results of L-shell spectroscopic analyses of Hybrid X-pinches (HXPs) employing an X-ray streak camera with a 10ps time resolution are presented. The goal of these experiments is to determine the plasma properties throughout the formation process of the X-pinch bright X-ray spots (hotspots). The most studied radiation from hotspots is K-shell radiation, although as previously demonstrated using streak cameras, K-shell radiation begins with a strong continuum followed by emission lines, which occur during the moment of maximum compression and the expansion phase respectively. [1] L-shell radiation can occur earlier in time as the temperature and density requirements are substantially lower, hence they can be used to shine a light on the early compression phase before maximum compression is reached. The experiments were conducted using the XP pulsed power machine with a current of 250-350kA and a rise time of 50ns. A variety of diagnostics in addition to a streaked X-ray spectrograph, including silicon diodes and PCDs, which were used to examine the L and K-shell emissions in time using an 8Ghz oscilloscope.