The Dual-Axis Radiographic Hydrodynamic Test Facility (DARHT) is a facility at Los Alamos National Laboratory which is part of the Department of Energy's stockpile stewardship program. It uses two large X-ray machines to record three-dimensional interior images of materials. In most experiments, materials undergo hydrodynamic shock to simulate the implosion process in nuclear bombs and/or the effects of severe hydrodynamic stress. The tests are described as "full-scale mockups of the events that trigger the nuclear detonation". The powerful pulsed X-ray beams allow for an ultra-fast motion picture to be constructed showing the details of the process being studied in three dimensions. The tests are compared with computer simulations to help improve the accuracy of the computer codes. Such testing falls under the category of sub-critical testing.

Los Alamos National Laboratory is one of the sixteen research and development laboratories of the United States Department of Energy (DOE), located a short distance northwest of Santa Fe, New Mexico, in the American southwest. Best known for its central role in helping develop the first atomic bomb, LANL is one of the world's largest and most advanced scientific institutions.