Electric field measurements from satellites-to-forbidden line ratios in an Omega-Upgrade laser-produced plasma. Final report, June 1, 1996--March 31, 1997

Abstract

Under this FY-96 NLUF program, the authors primarily carried out an initial search for satellite lines to forbidden transitions for localized laser-induced electric field measurements, using their flat-field grazing incidence spectrograph on the OMEGA-Upgrade facility at the University of Rochester Laboratory for Laser Energetics (LLE). In a second 1996 series of experiments carried out in September the authors were able to complete 19 shots using all 60 beams and spherical targets consisting of neon-filled microballoons with coatings of aluminum, magnesium and sodium fluoride, sometimes overcoated with a plastic (CH) layer. With cooperation from Dr. Paul Jaanimagi of LLE, they succeeded in adding a LLE streak camera for time resolution. The electric fields that they measured corresponded to laser irradiances comparable to those applied, accounting for some losses in the plasma. The details with figures are included in an attached preprint of a paper recently accepted for publication in the Journal of Quantitative Spectroscopy and Radiative Transfer (JQSRT) as part of the Proceedings of the November 1996 Conference on Radiative Properties of Hot Dense Matter at which the results were presented. They were also presented at the 1996 American Physical Society Division of Plasma Physics Conference in Denver in November 1996.