Time resolved interferometry of plasma radiation source loads

Models of imploding wire arrays usually assume an expansion and instantaneous ionization of the array material with the subsequent implosion proceeding as a distinct array of individual plasma elements or as a cylindrical shell. Experimental evidence indicates that precursor plasmas form and implode ahead of the array, x-ray pulse lengths are longer than 1D models predict, and part of the array mass is left behind. Interferometry with 10 to 1 magnification is used to probe the initial plasma formation processes. Results on Al and C loads indicate that neutral Al vapor cores or solid C cores persist for up to 400 to 600 ns into the current pulse, and that precursor plasma formation is possible. These results predict similar behavior for the first 40 to 60 ns on current generators with İ per wire − 1.4 MA/μs.