Chronology of a subcrit
Conducting a subcritical experiment requires many complex steps.
Preparing for and executing a subcritical experiment is a complicated process that can take more than five years from beginning to end. Los Alamos National Laboratory defines the subcritical experiments it needs to meet its responsibilities to the Stockpile Stewardship Program, and the Subcritical Experiments Council schedules those experiments for execution at the Nevada National Security Sites' (NNSS) Principal Underground Laboratory for Subcritical Experimentation (PULSE). ★
Here is a simplified look at the steps required to carry out a subcritical experiment:
- Identify the weapons-physics questions involving plutonium that Los Alamos scientists need answered
- Identify what subcritical experiment data will answer those questions
- Design the experiment
- Manufacture the subcritical experiment device and the accompanying equipment
- Develop the diagnostic measurements
- Prepare the PULSE facility
- Test the diagnostic, timing and firing, process control, and other systems
- Transport all parts of the device to NNSS
- Assemble the device at the Device Assembly Facility
- Transport the device to PULSE
- Insert the device into an underground zero room
- Connect the diagnostic measurement systems inside the vessels
- Conduct dry-run tests to ensure all systems are functioning correctly
- Emplace the device inside the confinement vessel
- Connect diagnostic systems from the vessel to the recording systems
- Conduct a final dry run
- Execute the experiment
- Entomb the used vessel
- Analyze data
