Radiative and dynamics features of uniform and combined multi-plane planar wire arrays studied on 1 MA UNR generator

Summary form only given. The planar wire arrays with multi-plane configuration (triple- TPWA and cross-plane-CPWA) were studied and compared with single and double-planar wire arrays (SPWA and DPW A) on the 1 MA, 100 ns Zebra generator at the University of Nevada, Reno. The uniform arrays were made of Al or Mo, and the combined made of both materials. The DPWA and TPWA consist of two and three wire rows, respectively, placed in parallel between the anode and the cathode. In a cross-plane load two single wire arrays cross under 90deg. The maximum power (1 TW) and yields (23-24 kJ) in short ns-scale rise-time x-ray bursts were observed for DPWA. The scaling shows that DPWA and TPWA yields do not drop rapidly as their width is decreased, and these arrays can be very compact (3-5 mm). In DPWA and TPWA the precursor is formed in several steps and in several locations, some of which do not coincide with the position of the stagnated plasma. Specific features of DPWA and particularly TPWA may open new paths for controlling the shape of radiation pulses. The CPWA implosion occurs in one step and the precursor position coincides with the position of the stagnated plasma which is the most uniform among planar wire arrays. For all planar arrays, the significant part of radiation at stagnation is associated with hot spots and radiation yields exceed conversion of the kinetic energy. A comparison of DPWA and cylindrical compact arrays indicates the possibility of the existence of the same plasma heating mechanism during the last several ns of implosion. Despite their very different implosion dynamics that continue even until 10 ns before stagnation, they form plasmas with similar temperatures and densities as well as generate similar powers and yields at stagnation. The possible heating mechanisms are discussed. The novel Wire Dynamics Model and MHD calculations which replaced the conventional 0D model are successfully used to model implosions of these complex wire arrays.