Multimegavolt water breakdown experiments

In the quest to develop current generators for high energy density physics experiments, Sandia national laboratories has long used water as an insulating media. Its high electrical breakdown strength and high dielectric constant corresponds to relatively compact energy storage components as well as low inductance spark gap switches. With the refurbishment of the Z machine underway, and with an eye towards the next generation of high current accelerators, an extensive research effort into water switches has been undertaken. A facility, called Z-20, has been built to within ZR operational levels to test the geometry transition and a variety of configurations of water switches. Particular parameters of interest are polarity and field enhancement dependence, prepulse level, gap spacing and threshold voltage levels.