Simulating the Demon Core: Bowling, Mission Impossible, and Nuclear Physics

The Demon Core and Criticality Accidents

• ⚠️ The Demon Core was involved in two fatal criticality accidents at Los Alamos, leading to the deaths of scientists Lewis Slotton and Harry Daghlian.
• 💡 The core's criticality was manipulated by bringing a beryllium reflector sphere closer, a process that tragically failed when a screwdriver slipped, causing a fatal radiation dose.
• 🧠 The internet is filled with memes about the Demon Core, highlighting its notoriety even among those with little nuclear physics knowledge.

Mission Impossible and Nuclear Pit Simulations

• 🎬 The movie Mission Impossible: Fallout features a scene with three plutonium cores, prompting speculation about their criticality.
• ⚛️ A nuclear engineer named Gavin Ridley used OpenMC software to simulate the criticality of the movie's prop cores, which were based on real dimensions from a prop auction.
• 🧪 Simulations revealed that the movie's prop cores, lined with borated polyethylene, would likely not go critical.

Nuclear Bowling and Pit Interactions

• 🎳 The video explores the hypothetical scenario of "nuclear bowling," where plutonium pits are used as bowling balls.
• 📊 Simulations using two Demon Core-sized pits showed a K effective value of 0.836, indicating they would be subcritical even when touching, due to factors like hollow cavities and being part of larger weapon assemblies.
• 📈 However, arranging multiple pits in 2D or 3D configurations can lead to criticality: six pits in a 2D layout or five in a tetrahedral stack become critical.

Plutonium Density and Criticality

• 🔬 A key discovery was the importance of plutonium's delta phase, which has a lower density (around 16 g/cm³) compared to the alpha phase (19.84 g/cm³).
• 💡 Using the lower density delta phase in simulations for the movie's props resulted in a K value of 0.945 (subcritical) with a borated liner, but a K value of 1.001 (slightly supercritical) with a regular plastic liner.
• 💥 If pits were large enough to go critical upon impact, the result would likely be a small chemical explosion with a blue flash, rather than a full nuclear detonation, due to rapid heating and expansion of the plutonium.

Other Scenarios and Conclusion

• 🎱 A simulation involving a beryllium-lined pool table with plutonium alpha-phase balls showed it could become critical upon breaking the rack.
• 🤔 The author's preconceptions about the inherent danger of the "cursed bowling ball" were proven false; weapon pits are designed with safety in mind, accounting for neutron reflection and hollow cavities.
• 🚀 The video concludes by referencing the Morrison case used for the Manhattan Project, highlighting the historical context of handling nuclear materials.