TY - JOUR T1 - Timely Verification at Large-Scale Gas Centrifuge Enrichment Plants AU - Mark E. Walker, Robert J. Goldston PY - 2017 T2 - Science & Global Security SP - 59 EP - 79 VL - 25 IS - 2 N2 - This article examines challenges in international nuclear safeguards pertaining to the timely detection of highly enriched uranium production at large-scale gas centrifuge enrichment plants. To establish where present gas centrifuge enrichment plant safeguards measures and approaches could be strengthened, we have created a discrete time model for simulating hypothetical misuse scenarios, both through transient phases and at steady-state. We find that timely detection of misuse at modern large-scale facilities presents a challenge for international safeguards. A toolbox of unattended measurement systems, along with remote monitoring, however, could be used to improve detection timeliness, enabling the initiation of follow-up activities, potentially on a rapid time scale. These measures, which would need very low false alarm rates, should be implemented in a graded approach, depending on the characteristics of each enrichment plant and an analysis of plausible acquisition paths for the State in which it is situated. Some of these technologies could provide significant benefit to plant operators. UR - http://scienceandglobalsecurity.org/archive/sgs25walker.pdf 0