PIM-a Blumlein driven IVA machine

The PIM machine has been designed and constructed at AWE to develop IVA technology for flash radiography of hydrodynamic experiments. While it was originally conceived as one module of a ten module, 14 MV, 100 kA machine versions operating at up to 3 MV are of interest to satisfy future radiographic applications at AWE. The IVA architecture will enable these machines to be relatively easily configurable in either negative or positive polarity allowing the diode to be either the self magnetic pinch type already in use at AWE or a rod pinch diode to achieve smaller radiographic spots. A Marx generator drives a 1.7 MV, 10 ohm water Blumlein initiated by twin radial laser triggered switches. The Blumlein has been used to drive either one or two parallel inductive cavities to obtain an output of 1.5 or 3 MV with a current of up to /spl sim/150 kA or >50 kA respectively. Prepulse suppression is provided by a gas prepulse switch in the coaxial oil feed from the Blumlein to the cell or cells. The latest results of the testing of the laser triggering system and the prepulse reduction system will be presented.