Shock Wave Generator for Iran’s Nuclear Weapons Program: More than a Feasibility Study

A copublication of Institute for Science and International Security and Foundation for Defense of Democracies (FDD) Shock Wave Generator for Iran’s Nuclear Weapons Program: More than a Feasibility Study By David Albright and Olli Heinonen May 7, 2019 • The Iranian Nuclear Archive reveals that under its early 2000s nuclear weapons program known as the “Amad Plan,” Iran was developing and manufacturing a key nuclear weapon subcomponent called a “shock wave generator.” The shock wave generator is a multi-point initiation (MPI) system, which has the purpose of uniformly initiating a spherical shell of high explosives, or the “main charge,” which in turn compresses the nuclear core made from weapon-grade uranium to achieve a supercritical mass for a nuclear explosion. Iran’s Nuclear Archive, a significant portion of which Israel seized in January 2018, is a curated set of highly sensitive nuclear weapons information detailing the Amad program’s effort to develop and manufacture five nuclear weapons and prepare an underground nuclear test site for possible use. • The development of the shock wave generator, also known as distributor, contributed importantly to Iran’s miniaturization of a nuclear weapons design. • A key associated Amad Plan facility was near the village of Sanjarian, called the “Sanjarian facility.” It made high explosive parts for the shock wave generator and conducted a range of tests for its development. In addition, under the Amad Plan, it was a center for the testing of exploding bridgewires (EBWs), which were necessary for the shock wave generator. Its nuclear weapon-related activities after the Amad Plan remain to be determined. • The Sanjarian building held two blast chambers, called Upper and Lower Nour-Abad, which were used in the Amad Plan, and perhaps afterwards, to test EBWs, the shock wave generator, and other subcomponents. One chamber was outfitted with a high speed camera. A full-scale, hemispherical test of the shock wave generator, using sophisticated diagnostic equipment, was conducted at the Marivan site, according to the archive information. • The archive contains considerably more information about the shock wave generator and Iran’s nuclear weapons development and testing than can be presented in this report. That information – due to proliferation reasons – cannot be made public. • The archive indicates that Iran had completed almost two thirds of the tasks associated with the “Shock Generator Project” by around 2002. With an expected completion date of July 2003, Iran may have completed the additional, approximately third of the tasks just before the Amad Plan was downsized and reoriented in the fall of 2003. The exact status of this project at that time and its evolution after the fall of 2003 remains to be determined. • Foreign assistance from at least one former member of the Soviet nuclear weapons program was key to Iran’s development of this MPI technology. • Preserving these complex nuclear weapons capabilities was a priority for Iran in the post-Amad reorientation plan. After 2003, the Shock Generator Project activities and Sanjarian facility were provided with a cover purpose of performing non-nuclear military and non-military explosive tests, and some activities were shifted to universities, such as Malek Ashtar University of Technology, and research institutes. Iran prioritized maintaining the project’s workforce. The status of these activities is unknown today, but the archive information indicates that they may continue. The Organization of Defensive Innovation and Research (SPND) is the latest known incarnation of the reoriented Amad Plan that appears to have inherited the personnel and capabilities of the Shock Generator Project. • The archive information on the shock wave generator confirms and adds considerably to previous information on this MPI system assembled over a decade ago by the International Atomic Energy Agency (IAEA). • The IAEA needs to inspect the Sanjarian site and related facilities, examine relevant equipment and materials, and interview the personnel mentioned in the archive and from the IAEA’s previous, extensive work to understand the shock wave generator project. The IAEA needs to characterize the status of the program today, its work and associated equipment, and interview any related personnel. • Iran should be urged to cooperate fully in these investigations. In particular, no information or equipment should be destroyed, and no locations altered before the IAEA has completed its investigations. Those investigations should include weapons experts with proper clearances. At the end of the inspection process, proliferation-sensitive information and equipment, where on-going possession is not in line with Iran's undertakings under Article II of the Nuclear Non-Proliferation Treaty (NPT), should be destroyed irretrievably or removed from Iran in a verifiable manner.