Sandia National Laboratories’ Z machine, the world’s largest producer of X-rays, shook the ground for several hundred yards in every direction for the first time since July 2006, when the 22-year-old facility was gutted to undergo a complete refurbishment at a total project cost of $90 million.
Z has been overbooked in recent years with requests for experiment time from national labs, universities, and the international community. The facility is in demand because of Z’s capability to subject materials to immense pressures, compress spherical capsules to produce thermonuclear fusion reactions, fire objects much faster than a rifle bullet, and produce data for models of nuclear weapons effects — as well as, more arcanely, the conditions surrounding black holes in space. Given its complex mission, it was time for a more modern Z.
The improved version is capable of firing more often, at higher energies, and with improved precision.
Sandia is a National Nuclear Security Administration laboratory.
The new facility - optimized for both z-pinch and material properties work - will increase the strength of its electrical pulse from 18 million amps to an anticipated 26 million amps. The facility also now offers improved control over the shape of its electrical pulse for better reproducibility as it enters new experimental regimes.
A z-pinch is so named because the large current passing in the vertical direction - the Z direction in cylindrical geometry - creates a magnetic field that pinches together the ions of thin wires that serve as electrical conductors until the current vaporizes them.
The 17.5-million-amp shot that signified the reopening of the facility was used to test new system components. It concluded an extensive facility outage during which the old pulsed power systems were removed, and the tank structure that contains the accelerator was extensively modified. New, more robust pulsed power components and subsystems were installed. Utility infrastructure modifications were made, and the accelerator subsystems were commissioned. Over the next several months, Z will conduct more tests to verify, validate, and optimize the performance and predictive models for the accelerator and determine reliable operating points for science program operation, the ultimate purpose for Z.