Then & now

Los Alamos’ Dual-Axis Radiographic Hydrodynamic Test facility

By Whitney Spivey | December 13, 2021

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Los Alamos National Laboratory

In 1994, construction (pictured) began on the Los Alamos National Laboratory’s Dual-Axis Radiographic Hydrodynamic Test (DARHT) facility. Each of DARHT’s axes contains a very large and very fast machine that produces radiographs (x-ray images) of materials that implode at more than 2.5 miles per second. Such radiographs allow scientists to “see” inside a mock-nuclear weapon as it detonates inside a spherical confinement vessel.

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DARHT today

The location where that confinement vessel sits is called the firing point, and until recently, the firing point was outside, at the intersection of the two axes. Because of this exposure to the elements, DARHT tests were sometimes delayed because of weather.

But in July 2020, a weather enclosure was completed around the firing point, creating a predictable and consistent environment for experiments. At the same time, the enclosure shields the facility’s high-tech camera system and other complex diagnostics equipment from poor weather conditions.

For more on DARHT, read "A day at DARHT" in the October 2018 issue of NSS