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Sandia has successfully integrated the capability to apply uniform, high magnetic fields (10-30 T) to high energy density experiments on the Z facility. This system uses an 8-mF, 15-kV capacitor bank to drive large-bore (5 cm diameter), high-inductance (1-3 mH) multi-turn, multi-layer electromagnets that slowly magnetize the conductive targets used on Z over several milliseconds (time to peak field of 2-7 ms). This system was commissioned in February 2013 and has been used successfully to magnetize more than 30 experiments up to 10 T that have produced exciting and surprising physics results. These experiments used split-magnet topologies to maintain diagnostic lines of sight to the target. We describe the design, integration, and operation of the pulsed coil system into the challenging and harsh environment of the Z Machine. We also describe our plans and designs for achieving fields up to 20 T with a reduced-gap split-magnet configuration, and up to 30 T with a solid magnet configuration in pursuit of the Magnetized Liner Inertial Fusion concept.

Cylindrical implosion offers a path to extreme material states, reaching considerably higher pressures than planar geometry. However, diagnosing compressed material in cylindrical geometry is challenging. Time-resolved velocimetry, a standard technique in planar compression, is difficult to incorporate into cylindrical experiments. This paper describes the use of photonic Doppler velocimetry (PDV) in magnetically driven cylindrical compression experiments at the Sandia Z machine. With this diagnostic, it is possible to track the interior of an imploding cylinder beyond 20 km/s. A "leapfrog" implementation is described to support velocities well above the bandwidth limits of standard PDV measurements.