25th Anniversary of the Joint US-Russian Disk EMG Experiment

Twenty-five years ago, on September 22, 1993, an event, unprecedented in the nuclear age, took place at Arzamas-16, Russia, as the All-Russian Scientific Research Institute of Experimental Physics (VNIIEF) and the Los Alamos National Laboratory (LANL), the two institutes that designed the first nuclear weapons of their respective nations, combined capabilities to conduct a joint scientific experiment. The experiment used a VNIIEF disk explosive magnetic flux compression generator (EMG) with an electrically exploded foil opening switch (FOS) to transfer multi-megajoule pulse of electric energy on a microsecond timescale to a magnetic implosion assembly. Despite a breakdown in the transmission line, the experiment delivered a load current of 20 MA, then-unattainable in stationary laboratory-scale experiments, and drove an electrically exploded liner to a velocity of 25 km/s. The experiment demonstrated the applications of the EMG-based pulsed power system to high energy density research, and resulted in the subsequent expansion through the 1990s and into the 2000s of joint VNIIEF/LANL EMG-enabled work on imploded liners and their applications. The success of the joint efforts led to new projects in plasma physics and fusion research, materials science, and driver technology development; and set the stage for additional programs in material control and accountability and several other high level international agreements on cooperation. The collaboration between VNIIEF and LANL demonstrated that joint efforts can deliver results not heretofore attainable through the efforts of any one institution. The results of this work constitute important milestones in physics and engineering development and are widely used today. These results include but are not limited to the following: •Magnetized hot plasma studies as applied to fusion ignition in MAGO-MTF systems; •Record-setting liner energy in the HEL-1 experiment (the 25-MJ record of this experiment has not been beaten yet) making the liner suitable for plasma compression in the MAGO-MTF system; •Use of disk EMGs with FOS to drive condensed-matter liners and to study materials properties (ALT-1, 2, RHSR-1, 2 experiments).