1FRAME: Collaborative R&D Focused on Neutron Detection, Analysis, and Simulations

Small-scale fuel debris removal operations are underway at Fukushima Daiichi nuclear power station ( 1 F ), which large scale operations coming in future years. The 1FRAME ( 1 F Fuel Retrieval and Monitoring Experiments) project is a collaborative R&D project with Japan and France focused on neutron detection, analysis, and simulations. This project aims to demonstrate that system multiplication can be inferred with limited assumptions measured in very challenging environments. Neutron detection work is focused on evaluating detector systems for use in high gamma flux environments and demonstrating that these systems can be used to infer system multiplication. Neutron analysis work will demonstrate that real-time analysis can be successfully performed to infer multiplication without assumptions of detector efficiency nor reactor kinetics parameters. Simulation work will produce radiation transport models which can be analyzed in a similar manner to measured data for complex 1F models. Demonstrations will be performed via measured and simulated data using both existing and new experiments. These demonstrations will include blind tests in which the operators do not know the system conditions. The advances produced in this work can be applied in other areas such as nuclear criticality safety, reactor startup, and safeguards.