Ceci N’est Pas Une Bombe: Lessons from a Field Experiment Using Neutron and Gamma Measurements to Confirm the Absence of Nuclear Weapons

Eric Lepowsky, Manuel Kreutle, Christoph Wirz, Alexander Glaser

Research output: Contribution to journalArticlepeer-review


In March 2023, the UN Institute for Disarmament Research held a verification experiment that included a mockup onsite inspection at a former military facility in the municipality of Menzingen, Switzerland. The experiment included a visit to the site by an inspection team, accompanied by the host team. Among other activities, radiation measurements were used to confirm the non-nuclear nature of selected items stored onsite. In this paper, we discuss the neutron and gamma measurement systems used during the experiment and the inspection protocols followed to confirm the absence of nuclear weapons. Results from the experiment and a laboratory reproduction are presented, before concluding with lessons learned for how absence-confirmation measurements can help support verification of future arms control agreements.

Original languageAmerican English
Pages (from-to)56-67
Number of pages12
JournalScience and Global Security
Issue number3
StatePublished - 2023

ASJC Scopus subject areas

  • General Engineering

Cite this